[Diagnosis of tumor-like fundus changes by means of a combination of echography, infrared photography and fluorescein angiography (author's transl)].

Using a combination of echography, infrared photography and fluorescein angiography in tumor simulating changes of the fundus an optimum combination of these diagnostic methods was achieved. The echography allows exact measurements of the prominence and in lesions exceeding 1.1 to 1.5 mm also a tissue differentiation. By infrared photography melanin could be differentiated from the bloodpigments and lipofuscin and the extension of pigmented tissues could be revealed. Fluoresceinangiography visualizes the vascular pattern and the permeability of the vessels of tumors or pseudotumors. Up to now 100 cases with tumorlike fundus lesions were subjected to this combined examination method and many of these cases preserved from enucleation.


[Fundus changes in scleroderma (author's transl)].

12 patients with scleroderma were submitted to an ophthalmological examination. 9 patients displayed fundus changes. In 7 cases defects of the retinal pigment epithelium near the macula were observed, one of these patients showed an associated serous detachment of the pigment epithelium. In three patients localized retinal vascular changes, especially on the capillary level, were notices. Obviously, alterations of the collagen as well as vasopathological changes being part of the systemic disorder do have their counterpart of the systemic disorder do have their counterpart within the eye.


[The relationship of the collapse-phenomenon on the disc to the pulsatory variations of the intraocular pressure (author's transl)].

The collapse-phenomenon of the central retinal artery induced by compression of the eyeball and the pulsatory variations of the intraocular pressure were recorded simultaneously. The collapse-phenomenon indicating the systolic pressure of the ophthalmic artery was correlated to the peak and that indicating the diastolic pressure of the ophthalmic artery to the through of the pulsewave. This finding has to be taken into account when evaluating the curves delivered by Stepanik's ophthalmic artery-tonography.


[Current formation in the aqueous humor (author's transl)].

The localisation of deposits on the inner surface of the cornea can not be explained from the visible aqueous humor currents. Only with statistical methods could we find a flat vortex, which forms in a approximately triangular region behind the cornea and which is too slow to observe directly.


[Orbitopiezography and its clinical significance (author's transl)].

A new procedure of piezometry of the orbit with electronic recording of the data obtained is being described. The advantages offered by this method are the unprecedented possibility of conducting long-term tests, the high accuracy of the measurements (0.1 mm), and transpalpebral measuring involving a minimum of inconvenience to the patient; in addition to this, only one examiner is required. The clinical significance of orbitopiezography is demonstrated by a description of the possible significance of the data and their evaluation in the differential diagnosis.


[Unusual courses of orbit-floor-fracture (author's transl)].

Blunt trauma can lead to intra-orbital haemorrhage, which cause motility and sensibility disturbances typically found also in orbit-floor fracture. When there is also a fracture present, it can be problematic to give the function deficiencies their right causes. Spontaneous improvement of the defiencies can be expected in a reasonable percentage of cases. Operative revision therefore should not be performed in cases of doubt, or in any case not earlier than 14 days after the injury. In a severe stove-in orbit with enophthalmos and double vision the operation should be preformed within the first week. In some cases, however, residual diplopia can be expected in spite of optimal early therapy.


[Drainage of the vitreous body space in cases of intra-ocular infection (author's transl)].

In the last 2 years we saw eight cases with massive i.o.infection (panopht-almitis) following perforating injuries. We took measures as follows: After trepanation of the sclera we washed out the space of the vitreous body with diluted solution of Gentamycin and simultaneously we used massive systemic therapy of Gentamycin and of Penicillin. In this way we stopped the infection in four eyes and we were successful in maintaining in various degree the function of these eyes.


[Drugs with unwanted side-effects on the retinal vessels (author's transl)].

A review is given on systemically applied drugs, which may cause vascular disturbances of the retina with possible irreversible involvment of the ocular function. Based upon personal observations and reports in the literature a series of drugs with such side effects is reported. In particular, besides retrolental fibroplasia and complications which can be induced by oestrogens, drugs are described, which on the basis of an allergic reaction may produce retinal haemorrhages or occlusions of retinal blood vessels.


[Recurring retinal haemorrhages with tortuosity of the retinal arteriols (author's transl)].

Four young and healthy adults with tortuosity of the retinal arterioles of the posterior pole and recurring superficial retinal haemorrhages are described. Two of them had a suspected mild thrombocytopathy without clinical manifestations in other organs. Inheritance of the syndrome was not demonstrated and the pathogenic mechanism still remains obscure. All the described patients had been at risk of a retinopathy of praematurity. Knowing that familial retinal haemorrhages without retinal tortuosity do occur and retinal tortusity may persist as a minimal change of retinopathy of praematurity, it is suggested that this syndrome might be a combination of two entities.


[Acute myopia with increased intraocular pressure due to a decompensated juvenile diabetes mellitus (author's transl)].

We report on a 33-year-old woman, whose diabetes mellitus was kept under control with depot insulin and diet for 18 years. One evening she notices blurred vision in both eyes which markedly increased during the following days. We found flat anterior chambers, an increased ocular pressure up to 34 mm Hg, and a myopia up to-3,5 D. on both sides. Bloodsugar tests revealed varying results. After the diabetic metabolic state was normalized, the myopia and the raised intraocular pressure ceased to exist.


[Clinical patterns of Parinaud's syndrome (author's transl)].

In agreement with other clinical reports we observed in 20 patients that Parinaud's syndrome may be associated with other midbrain symptoms. Most frequently we found convergence insufficiency or pupillary changes. In contrast to textbooks in most cases that was an incomplete, absolute paralysis of pupillary constriction. Some patients had also paresis of the 3rd and 4th cranial nerve or lesions of the medial longitudinal fasciculus (internuclear ophthalmoplegia). All clinical patterns which we noted were understandable in view of the topographical relationship of their presumed lesions. However, none of the symptoms was invariably associated with Parinaud's syndrome.


[Light coagulation in central and paracentral choroiditis (author's transl)].

Since 1966 photocoagulation has been performed in 52 cases and 54 eyes of choroiditis located on the posterior pole. The course of the cases treated is compared with a control group treated with drugs. Photocoagulation shortens the duration of the acute inflammatory process, decreases the frequency of recurrences by about 40% and improves the visual prognosis. The follow-up 1 year to 9 years later (average 7 years) showed in the control group a visual function of 0.5, in the treated group of 0.8.


[Diagnosis of myasthenic eye signs. Clinical signs and electronystagmographical findings of saccadic eye movements (author's transl)].

The clinical eye signs of 31 myasthenic patients are presented and those signs important for an early diagnosis are then discussed: lid symptoms caused by fatigue (Simpson-test), characteristic lid twitches as well as alternating asymmetrical eye muscle pareses. The importance of an investigation with the tangent scale in the course of which tensilon is injected is pointed out. False diagnosis and differential diagnostic signs are then considered (disseminated sclerosis, aneeurysm, encephalitis, pseudopulbarparalysis). - Our electronystagmographical investigations of saccadic eye movements showed hypometric, alternating saccades with occasional nystagmuslike jerks. After Tensilon injection hypermetric saccades (overshoots) were observed which depended on a disproportion of the supranuclear oculomotor centers and the eye muscles. The "muscleparetic" nystagmus is a pathologically increased endposition nystagmus. The hypometric nystagmuslike jerks during a saccadic eye movement are caused by insufficient phasic innervation.


[Unilateral aphakia in childhood (author's transl)].

The monocular and binocular vision will always be disturbed after unilateral cataract extraction in childhood. The treatment therefore not only means operation, but also correction of the optic error, pleoptics and orthoptics. In 40 cases of unilateral aphakia (12 congenital, 28 traumatical) the prognosis depends on the age of the individual and maintenance of treatment. The older the child and the sooner therapy is started the better are the functional results.


[Convergence insufficiency and school difficulties (author's transl)].

124 lowgrade hypermetropic pupils aged from 6 to 9 years, with normal I.Q. showed exophoria for near vision combined with weakness of convergence and school difficulties in several disciplines. These were treated as follows: training of the physiological diplopy, training of convergence, and surgical treatment by unilateral or bilateral resection of the medial rectus (the last-mentioned method has been applied on failure of so-called "ophthalmologic home-work"). Results were satisfactory in only 19%. The subjective primary complaints, similar to asthenopy, disappeared within a few weeks (65%). The effect of ophthalmological treatment was examined by the school psychological service as to acceleration in learning. Supported by comparisable objective effects (reading- and writing tests) with 50 control persons an improvement of concentration and motivation (77% and 62%), of reading capacity (44%) and of writing capacity (42%) was obtained within a space of 6 weeks to four months. Without taking up a too great percentage of the available school time, more attention should be paid in the elementary school age to a more accurate examination of the eyes, in order to detect even minor defects.


[The mode of action of trabeculectomy (author's transl)].

We could ascertain the mode of action of trabeculectomy by clinical research in more than 370 eyes after the operation and especially by the injection of fluorescein into the anterior chamber in 90 of these eyes. The following drainage mechanisms of the aqueous humor were observed: 1. Outflow through new developed aqueous veins (trabeculectomy-veins), 2. Bulkflow through lymphatic vessels, 3. Diffuse resorption into the subconjunctival tissue, 4. Outflow through normal aqueous veins. The latter mechanism is seldom of great importance. In only three cases passed all of the visible aqueous outflow through normal aqueous veins. In these cases an opening of Schlemm's canal could be assumed. In all of the other eyes we could not find any evidence for an outflow through Schlemm's canal whether there was a filtering bleb or not. This means that from the presence or absence of a visible bleb no conclusion can be drawn as to the mode of action.


[Experimental fluorescence angiographic and microscopic investigations on laser treated animal eyes (author's transl)].

The effects of laser coagulation on rat fundi were studied angiographically and with the fluorescence microscope. The coagulations were performed using constantly 300 mW and 0.2 second exposure time and 50 microns spot diameter. We observed the animals for 3 months, after which we could still observe dye diffusion by fluorescence angiography. With the fluorescence microscope we could localize these diffusions as originating from neovascularisation starting from the choroid. These new vessels penetrated subsequently into the exterior retinal layers. At the beginning of our observation time, the retinal vessels showed some sinuosities, dilatations and solitary stenosis, but no disturbance of circulation was demonstrable.


[The diabetic retinopathy in the ophthalmologic practice (author's transl)].

155 patients with diabetic retinopathy (309 eyes) were treated with Dexium¿. Good results were seen in diabetics with simple retinopathy; there was no important change where proliferating retinopathy was present.


[Cryoapplication in a case of subconjunctival iris prolapse after cataract extraction (author's transl)].

A report is given on cryotherapy of a subconjunctival iris prolapse in a 46-year-old man 23 days after cataract extraction. The procedure is simple, without complications, and was in accordance with descriptions in the literatur also in this case successful.


[Partial closure of the central artery and vein of the retina in retrobulbar optic neuritis (author's transl)].

The changes in the fundus of a 57-year-old patient (perimacular turbid retinal oedema, cloudy peripapillary exsudates and peripheral retinal hemorrhages) could not be interpreted satisfactorly on a clinical basis. Histologic examination revealed a retrobulbar optic neuritis associated with round cell infiltrates around the central retinal blood vessels impeding their blood flow.


[The influence of refraction on diabetic retinopathy (author's transl)].

Two groups of patients with diabetic retinopathy were tested by refraction. Patients with advanced retinopathy and those with early diabetic retinopathy had about the same propor-tion of refractive errors as the normal population. The only important difference was seen in middle- and high myopic eyes, which occurred less frequently when diabetic retinopathy was present. Illustrated from 4 cases of high myopia the inhibitory influence of diabetic retinopathy on the formation of shortsightedness is shown. Possible causes for this are discussed.


[A case of monocular retinitis pigmentosa (author's transl)].

A 38-year-old patient showed monocular nonprogressing pigmentary changes for 8 years, with nearly normal blood vessels and scarcely restricted dark-adaptation. ERG and VER were different from those of the other eye. The affected eye had full vision and an annular scotoma corresponding to the pigmentary changes. The other eye was amblyopic due to strabismus. Phenotypes, similar to retinitis pigmentosa, and chorioretinitis diffusa are discussed. This is probably a congenital anomaly.


[Thoughts on phacoemulsification (author's transl)].

It is difficult to have a clear opinion about phacoemulsification since attitudes towards this method are at the moment controversal. The author tries to make judgment easier by discussing the contrary arguments.


[The Mackay-Marg-tonometer. A clinically applicable measuring apparatus for Pt-values (author's transl)].

Comparative pressure measurements on the corneae of enucleated eyes and on a 0.05 mm-thick rubber membrane showed that the Pt-values obtained by the MMT can be sufficiently exactly controlled. An air chamber attached to a Hg-manometer has in an upper wall a round window 8 mm in diameter, closed by a 0.05 mm-thick rubber membrane. The sensor of the MMT is mechanically fixed over the window so that the foot plate of the sensor indents the rubber membrane by 1 mm. The pressure in the chamber can be varied at will by vanying the amount of air in it.


[About the application of a new audio video color cartridge system in ophthalmology (author's transl)].

A report is given on an advanced color video cartridge system and its application within various disciplines of ophthalmology.


[An ophthalmologist's hints for organising medical help in remote areas of developing countries (author's transl)].

Judging by her experience gained in the south of Tunisia, the author suggests that instead of sending individual ophthalmologists to the developing countries it would be more advantageous to send mobile work teams in vehicles equipped with ophthalmological examination and surgical instruments and apparatus. This would be a suitable reply to the appeal made by the World Health Organization in 1973 for organising large-scale surgical treatment of cataracts with international participation within the framework of struggle against blindness in the world.


[Flow in natural and artificial organs and vessels (author's transl)].

After introductory remarks about the flow phenomena in the human body (separation, dead waters, stagnation regions) and the model simularity conditions, the flow behaviour in arterial bifurcations at pulsatile flow are considered; they are accompanied by the formation of dead waters and secondary flows and therefore they give the danger of atherosclerosis. Then the flow pattern at arterio-venous anastomosis is interpreted with regard to the danger of thrombogenesis. At the selected example of ball prosthesis the flow pattern and the pressure loss of artificial heart valves (aortic as well as mitral valves) are described; the special behaviour of ball valves used as mitral valves is discussed critically. Finally in a view of contribution to the question of the flow-induced blood damage, in extended series of basic tests on models (orifices and perforated discs) the rate of hemolysis was measured depending on the flow; the tests were completed by measurements at rolling pumps, atria of a artificial ventricle and other parts. In order to try an explanation for the flow-induced hemolysis one starts from the influence of the hemodynamic shear stresses on the damage of the erythrocytes; hereby the effect of the frequently repeated passages of the red blood cells through a stenosis (e.g. regurgitation) should be taken into account.


[Thermodynamic aspects of phagocytosis and thrombosis (author's transl)].

In this paper, thermodynamic considerations are applied to two biological processes, phagocytosis and platelet adhesion, the latter being an important step in thrombosis formation. Simple thermodynamic models in terms of changes of the Helmholtz free energy are presented for the engulfment of bacteria by phagocystic cells, as well as for the attachment of platelets to biomaterial surfaces. The interfacial tensions contained in the expressions for the Helmholtz free energy may be obtained from contact angles, by means of an equation of state approach. The in vitro phagocytosis tests show that hydrophobic bacteria are more readily phagocytized than hydrophilic ones, and the thermodynamic model elucidates the reason for this pattern of behaviour. Preliminary results for two types of platelet adhesion tests are presented. Although there is, in terms of simple thermodynamic considerations, a strong similarity between platelet adhesion and the early stages of phagocytosis, we anticipate that specific interactions will play a larger role in platelet adhesion than in phagocytosis.


[The self-organization of biological structures (author's transl)].

Viruses played an important role in analysing macromolecular structures. Structure and function in living systems are arranged hierarchically. An important purpose of biology is to describe the correlation between the structural hierarchy and the observed assembly and to analyse the embryological program of the organism.


[Transmembrane inward currents during excitation of the heart (author's transl)].

During excitation of the myocardial cell 2 transmembrane inward currents occur. The initial fast Na current is responsible for the upstroke of the normal action potential. The slow inward current is triggered at a threshold potential of about -40 mV and causes the plateau phase of action potential. Under physiological conditions Ca ions are the main charge carriers of the slow inward current. Both inward currents are mediated by 2 membrane channels which are independent from each other. The normal excitability of the myocardial cell depends upon the availability of the fast Na channel but the transmembrane Ca supply will be determined by the Ca conductance of the slow channel. After inactivation of the fast Na channel the excitability of the myocardial cell does not disappear completely. In this situation the slow inward current can mediate action potentials (so called Ca action potentials). The slow inward current can be considered as the predominant mediator of the excitation process in the pacemaker cells of the sinoatrial node and the av node. Specific inhibitors of the slow membrane channel (verapamil, D 600, Ni, Co, and Mn ions) block the transmembrane Ca current leading to excitation contraction uncoupling. The excitation process will be impaired only if it is carried by the slow inward current alone. Specific inhibitors of the fast Na channel reduce the Na-dependent excitability of the myocardial cell without significant changes of the Ca current. The existence of 2 separate channels in the ventricular myocardium allows selective alteration of contractility without concomitant changes of the Na-dependent excitation process or, conversely, the reduction of excitability whereas the Ca current remains unchanged.


Membrane-localized pyruvate kinase of red blood cells in hemolytic anemia associated with pyruvate kinase deficiency.

Pyruvate kinase activity of red blood cell membranes, which is normally masked, has been determined after mechanical disruption of the membranes in normal individuals and in three homozygous patients with pyruvate kinase deficiency. Although patients 1 and 2, who were siblings, had relatively high enzyme activities in their hemolysates, they had the severest form of the disorder. The activities of their membrane fragments were decreased to seven per cent of fragments of normal membranes. Patient 3 had a mild form of hemolytic anemia despite a low enzyme activity of his hemolysates. The membrane fragments of this patient contained 28 per cent of the pyruvate kinase activity of normal fragments. The data suggest a relationship between the amount of membrane-localized pyruvate kinase and the severity of the clinical disorder. The reduced production of ATP by the enzyme portion localized within the membrane may cause an impairment of membrane functions in pyruvate kinase deficiency.


Comparative studies of the electroencephalogram and the cerebral oxidative metabolism in patients with liver cirrhosis.

In two groups of patients with liver cirrhosis and normal EEG (Group A) and with pathological EEG (Group B) it was possible to demonstrate a correlation between the severity grade of the EEG changes, the livertypical deviations of serum chemistry and alterations in cerebral oxidative metabolism. The metabolism of the brain showed a reduced oxygen consumption and carbon dioxide output in the patients with pathological EEG changes. All patients showed a raised glucose uptake, an increased lactate release, a raised ammonia uptake and glutamine output. These findings in patients with liver cirrhosis indicate a disturbance of the oxidative energy metabolism of the brain with secondary intensification of glycolysis. Pathological changes in the EEG only appear if the oxygen consumption of the brain is limited (as in the patients of Group B). These EEG changes have a poor prognosis in respect to life expectancy. With consideration of the data from animal experiments and the reported results of cerebral blood flow and oxydative metabolism in patients with liver cirrhosis it might be assumed that liver insufficiency with elevated serum ammonia results in a deranged oxydative cerebral metabolism which might explain hepatic encephalopathy.


Changes of plasma renin, angiotensin II and renin substrate during reversal of malignant renovascular hypertension.

The relationship between plasma renin activity (PRA), angiotensin II (AT II) and renin substrate concentration (PRS) were studied in a patient with left renal artery occlusion and malignant hypertension before and after left-side nephrectomy. Initially, PRA and AT II were grossly elevated, while PRS was low. Treatment with alpha-methyl-DOPA and saline led to a fall in PRA and AT II and a large rise in PRS. The correlation between PRA and AT II (r=0.937; n=9, p less than 0.001) was highly significant. PRA and PRS were negatively correlated before operation (r=-0.78; n=6; p less than 0.05). A comparison of changes in PRS before and after nephrectomy suggests that renin substrate formation was increased when the ischemic kidney was still in situ. Following nephrectomy, PRA and blood pressure fell to normal within 5 hours, while PRS remained unchanged for this period of time. A two-compartmental analysis of the renin disappearance curve after nephrectomy revealed the presence of a fast and slow component with half-lives of 10 and 95 min, respectively.


[The effect of acetylsalicylic-lysine on platelet function (author's transl)].

Fifteen minutes after the intravenous administration of two different doses of acetylsalicylic lysine, a pronounced inhibition of collagen-induced platelet aggregation was observed in healthy volunteers. A proportionate dose response to the differing doses could not be demonstrated. Platelet function investigated by the glass bead filter method according to Hellem decreased however significantly and dose-dependently after the injections. The clot formation in the thromboelastogram was not disturbed after the administration of the drug in spite of decreased platelet function.


[Use of sodium chloride in the German Federal Republic (author's transl)].

In order to obtain data on the amount of sodium chloride used in the German Federal Republic, 106 persons of different social groups, with healthy kidneys, were investigated, measuring the sodium chloride contents in their 24-hour urine. The sodium chloride intake follows from the sodium chloride secretion because the regulation of the sodium household is effected through the renal excretion, and with healthy people the daily intake of sodium chloride down to a limit value of 200 mVal per day is eliminated without delay. The values measured are between 4.7 and 32.7 g, the mean figure corresponded to 13.1 g.


[Immunological studies on glucosephosphate isomerase deficiency: instability and impaired synthesis of the defective enzyme (author's transl)].

The content of GPI protein in normal and GPI deficient red cells was studied by immunological methods. In normal cells almost all enzyme protein is catalytically active. In the four inherited variants with non-spherocytic hemolytic anemia studied the content of GPI protein was decreased to a variable degree. Furthermore, the catalytically active portion of GPI protein varied markedly. It can be concluded that in the pathogenesis of this hereditary disorder an increased lability as well as an impaired synthesis of the defective enzyme play a role.


[Determination of the mechanical parameters of the cupulo-endolymphatic system from its anatomical characteristics].

The relationships which allow measurements of the mechanical parameters of semicircular canals, i.e. time constants and sensitivity to the angular velocity, from their anatomical characteristics have been established. The sensitivity varies in different animal species and in different canals of the same animal. This should be taken into consideration in the experimental studies of the function of semi-circular canals of animals and humans.


[Change in the content of free amino acids in rat organs and tissues during hypokinesia].

Variations in the content of free amino acids in the gastrocnemius muscle, myocardium and plasma of rats were measured during hypokinetic and post-hypokinetic periods. It was shown that 35-day hypokinesia led to an increase of almost all amino acids in the gastrocnemius muscle and 60-day hypokinesia resulted in their decrease. Similar changes were followed in the myocardium. Variations in the content of free amino acids in the plasma were identified at every experimental stage. Changes in the protein metabolism persisted long after an exposure of the animals to prolonged hypokinesia.


[Biorhythmic selection of cosmonauts].

The paper describes some features of modern and future interplanetary space missions which may influence the stability of the circadian system of the human body. It presents requirements for biorhythmological selection of cosmonauts. The paper discusses the biorhythmological types of humans: biorhythmologically labile, biorhythmologically inert and intermediate. The time schedule specified by the flight program dictates the selection of the cosmonauts of a certain type for the given mission. The paper suggests methods for the biorhythmological selection of cosmonauts: 1) on the basis of adaptation to the concrete type of "space day" in the flight; 2) on the basis of the biorhythmological type; 3) on the basis of the length of the natural circadian period; 4) on the basis of typological features of the nervous system.


[Ocular effects of cosmic rays on the eyes].

The observed visual phenomena developing in humans as a result of the impact of heavy ions on the eye have been summarized. Possible mechanisms of these effects are discussed.


[Changes in acoustically evoked brain potentials during oxygen breathing at normal and increased pressures].

Acoustically evoked potentials of the human brain were studied when breathing pure oxygen at a normal and positive pressure. An exposure to pure oxygen at a normal pressure reduced the amplitude of evoked potentials. This effect was more pronounced at a positive oxygen pressure. The after-effect was prolonged due to the influence of an increased oxygen concentration. During an exposure to the air at a positive pressure the reduction of the amplitude was smaller and reached the pretest level as soon as the pressure returned to normal. Evoked potentials are a sensitive indicator of the effect of an altered atmosphere on the central nervous system and the sensory system.


[Effectiveness of a helium-oxygen gas mixture in transverse accelerations].

Healthy male test subjects, aged 20 to 45, were exposed to acceleration of +6 Gx for 1200 sec and of +10 Gx for 60 sec. Three gradients of the centrifuge acceleration were used in the latter case. In every experimental run the test subjects were exposed to accelerations while breathing air or a helium-oxygen atmosphere. The positive effect of the helium-oxygen atmosphere was seen in an increase of the respiration intensity and in an elevation of pulmonary ventilation and gas exchange. This may be associated with a decline of the aerodynamic resistance to breathing. The positive effect of the helium-oxygen atmosphere was more pronounced during accelerations of +4 to 8 Gx and depended on the total exposure time.


[Effect of accelerations, hypergravity and hypokinesia on protein metabolism in Japanese quail. I. Effect on muscle composition].

The effect of hypokinesia, hypergravity achieved by centrifugation and additional weight load on the content and composition of proteins and nucleic acids in the chest and pelvic muscles of four groups of quails (Coturnix coturnix japonica) was studied. The first group was used as controls, the second included hypokinetic birds, the third was made of birds with an additional weight load (the load was a double weight of the animal) and the fourth group included birds exposed to acceleration of 3 g. The birds were exposed to the above effects for 1 to 6 hours during 8 days. They were given identical food through forced feeding. The content of total proteins, sarcoplasmatic proteins, DNA and RNA, cholesterol and esterified fatty acids was measured in chest and pelvic muscles. The composition of total lipids was examined in pelvic muscles. The level of corticosterone was determined in the blood plasma. The above experimental variants made it possible to discriminate individual contributions of acceleration, additional weight load and hypo-inesia to the effect. Weight load and acceleration decreased and hypokinesia increased the content of total proteins in the pelvic muscles. During an exposure to acceleration and hypokinesia the content and the portion of sarcoplasmatic proteins decreased and during an exposure to weight load increased significantly. Acceleration did not exert a significant effect on the RNA and DNA content in muscles. The content of esterified fatty acids increased under the influence of acceleration and hypokinesia and decreased significantly under the influence of additional weight.


[Physiological activity of Chlorella following exposure to space flight factors aboard the orbital station "Saliut"].

The photosynthetic activity of Chlorella vulgaris str. LARG-1 was studied after its dark exposure in the Tamiya medium to space flight factors enboard the Salyut orbital station. The exposure of Chlorella cells in the inactive state did not influence their basic physiological parameters (rate of growth and reproduction, cell size and population structure, chlorophyll content, cell viability) during subsequent intensive cultivation. These results show the possibility of storing the generative material of unicellular algae under the experimental conditions.


[Effect of a strong constant magnetic field and a hypomagnetic surrounding medium on histochemical indices of albino rat liver].

The paper presents histochemical measurements of the liver of white rats exposed to strong and weak constant magnetic fields. A repeated influence (30 min a day) of the strong magnetic field of 912 ersted for 16 days inhibits synthetic processes in the liver tissue. A more prolonged (30 days) exposure to the field produces insignificant histochemical changes which seem to be induced by the occuring compensatory reaction. It is shown that a month long stay of animals in the environment shielded from the geomagnetic field may enhance synthetic processes in some cells and inhibit them in others.


[Human tolerance to +Gz acceleration during heating].

Eighty-six measurements of individual tolerance of 25 healthy test subjects to +Gz accelerations were carried out at two body temperatures. At moderate heating (body temperature 37.5+/-0.2degreesC) acceleration tolerance decreased by 1.4 g (maximally by 3 g) without an antigravity suit and by 0.5 g with an antigravit suit. In case of simulated poor fitting of the suit the tolerance decrease was 1.1 g. At high heating (body temperature 38.0+/-0.2degreesC) the decrease was great (2.1 g). In some cases centrifugation was terminated because of poor tolerance to hyperthermia. The regression analysis suggests that at body temperature of 37.3degreesC the acceleration tolerance decreases in some individuals only and at 37.6degreesC and over it declines in most subjects. The correlation between the level of water losses (0.8--2.4% of body weight) and decline in +Gz tolerance was low (r=0.33) and insignificant. The resulting data allow practical recommendations in relation to acrobatic flights in hot climate.


[Adaptation of the cardiovascular system to negative gravitation stresses during repeated antiorthostatic measures].

The cerebral, pulmonary, liver and peripheral circulation was studied simultaneously in 12 test subjects (aged 24--30) rheographically, photoplethysmographically and rheoplethysmographically; arterial pressure was measured by the Korotkoff method. The measurements were carried out during three antiorthostatic tests at --15degrees for 20 min or --30degrees for 20 min. It was shown that the cardiovascular system can adapt to repeated antiorthostatic exposures. The adaptation includes more significant decrease of the heart rate, increase in the systolic and pulse arterial pressure, fall of the diastolic arterial pressure, more marked reduction of antiorthostatically induced increase of blood filling and congestion of cerebral and pulmonary vessels, lesser decrease of their tone and blood redistribution into the vessels of the liver, upper and lower limbs. From the point of view of the adaptive effect repeated exposures to --15degrees are more effective.


[Interrelation of visual and auditory analyzer functions during extreme stimulation].

By psychophysiological methods the effect of intensive photostimulation on the functional state of the optic analyzer and the influence of extreme optic stimulus on the hearing function were studied. An impulse acoustic stimulus contributed to the recovery of peripheral light sensitivity, left unchanged the central light sensitivity, improved acuity of color distinction, expanded the field of vision of red and green colors and reduced electric sensitivity and critical frequency of disappearance of light flashes. After an exposure to a superbright flash a decrease of absolute thresholds of hearing, electric sensitivity and critical frequency of fusion of electric stimulation of the acoustic analyzer was detected. These data give evidence that sensitivity of one analyzer can be increased by means of short-term intensive stimulation of the other.


[Human cognitive activity during adaptation to short-term weightlessness].

The differences in subjective sensations during the first exposure to short-term weightlessness are analyzed on the basis of the pattern of cognitive activity of test subjects and the scope of information they have received previously. The subjects with objective and productive types of cognitive behavior showed the most adequate and rapid adaptation to weightlessness. The subjects with a subjective and unproductive type of cognitive tactics exhibited great problems in adapting themselves to weightlessness, showing unusual psychic states like the "world peril" syndrome and psychic estrangement. Anticipation of the weightless environment based on the objective information previously obtained facilitated orientation and self-control in weightlessness.


[Study of the dynamics of psychic work capacity of hypertensive flight personnel for the purpose of predicting their professional activity].

One hundred members of the flying personnel with hypertensive disease (of the I and II stages), aged 35--50, were examined. The examinations included clinical and psychological observations which described functional and psychological potentialitites of the test subjects. Statistically significant differences in the average productivity of mental work were found in hypertensive and control test subjects. Individual characteristics of the prolonged and intensive mental activity was determined. This makes it possible to reveal consistent tendencies characterizing different disturbances in mental performance. Clinical and psychological investigations allow objectivization of qualitative features of disorders in mental capacity typical of the I and II stages of hypertension. They are helpful in predicting professional reliability of the flying personnel. Therefore, they should be taken into consideration in solving expertise problems.


Spleen and liver weight changes in NZB mice with haemolytic anaemia.

Spleen and liver weights from 998 NZB mice were subjected to computerised multivariate analysis. 3-dimensional graphs relating predicted spleen and liver weights to age and bodyweight were prepared and the relationship of the fitted surface to the histology and pathological autoantibody is discussed. On the basis of spleen weight increase, red-cell destruction throughout the greater part of life seems to be mainly intrasplenic, while intrahepatic destruction does not become important until later, when it is probably a dominant feature in the terminal period of the disease. Only limited organ weight increases occur in breeding females, and it is suggested that pregnancy lessens the effect of the haemolytic disease, the 'protective' effect extending long after the cessation of breeding.


The Mongolian gerbil: qualitative and quantitative aspects of the cellular blood picture.

The gerbil displays sex determined differences in packed red-cell volume, haemoglobin level, total leukocyte count and absolute number of circulating lymphocytes. The erythrocytes demonstrate a prominent polychromasia and frequent occurrence of basophilic stippling.


[Human work capacity at high altitudes].

Healthy male test subjects (students), aged 18 to 24, dwelling in lowlands ascended a mountain of 3200 m without preliminary training. At high altitude they went in for gymnastics and sorts games for 1--2 hours a day and made regular ascents, reaching an altitude of 4000 m. This was designated a pulsating regimen of adaptation. Phasic changes in the maximum physical performance were noted during a short-term exposure to high altitudes (3200 m): during the first decade it declined by 12--13% and by the 41--42 day the performance increased by 25%. During the readaptation period the performance remained for 2 months higher by 28--35% than the pretest values. The pulsating regimen of adaptation to highlands can be used to increase physical performance of the human body during and after the exposure to high altitudes.


A discounted least squares quadratic growth prediction model for use in 2 year toxicity studies.

Weekly weighings of the laboratory rats are required to determine the correct dosage for mixing in the food. This creates problems in that the food mixing must be done immediately after the weighings and staff are often heavily taxed to perform the task. A discounted least squares growth prediction model allows for prediction of weights a week ahead of time, obviating the necessity for instantaneously processing the weight data. When dosages were prepared based on these predictions, for 10 treatment combinations 100% of the doses proved to be within 8-0% of the required dosage; 98-4% were within 5% of the required dosage; 78-7% were within 2% of the required dosage; and 51-6% were within 1% of the required dosage. The quadratic weight prediction model can also be incorporated into a model for predicting food consumption.


X-ray enlargement modified for use in experimental animal science.

The primary enlarged x-ray image is produced by a reduction of the focal-film-distance to 80 cm at a given focal size of 0-15 mm. The advantages of this technique as compared to conventional x-ray methods are exemplified with x-ray images from the shoulder joint of a European hamster, a pseudoarthrosis in the foreleg of a beagle, and a renovasography of a rat. The principles of the technique and its significance for investigations using small laboratory animals are discussed.


Production of rats in synchronised batches.

Successful synchronisation of copulations and births for the 1st parity permit continued synchrony of parturitions in subsequent parities. Foetal implantation after post-partum copulation was delayed by multiples of the oestrous cycle; both season and number of sucking neonates influenced the time of implantation. Post-weaning matings gave a high conception rate with a parturition spread of 36 hours for 94% of the original group.


Solid intraperitoneal Landschütz tumour in mice: implications in cancer chemotherapy and immunology studies.

Multiple intraperitoneal injections of various normal sera into BALB/c mice inoculated intraperitoneally with Landschütz ascites tumour cells abrogated the development of ascitic syndrome in almost all the animals. In a large proportion of the survivors solid intraperitoneal tumours developed, composed of characteristic ascites tumour cells engulfed and encapsulated in connective tissue. The effect of serum on the development of the solid tumour was diminished if the donor had been immunized against mouse IgG. Inoculated animals treated with serum hyperimmune against mouse IgG showed accelerated ascitic tumour growth. Cyclophosphamide or arabinosylcytosine strongly inhibited growth of solid tumours. Simultaneous administration of arabinosylcytosine and its antagonist cycloheximide did not interrupt tumour growth.


[Evaluation of the effect of impact stresses on the body according to laboratory study data].

In three experiments on white rats and in two experiments on volunteers variations of 20 clinical and laboratory parameters were investigated upon an exposure to impact accelerations. The results demonstrated a correlation between changes in the general state of the animals and morphology of viscera, on the one hand, and changes of hematological and biochemical parameters, on the other. A scheme of utilizing more informative parameters for the in vivo differentiation of effects of impact accelerations is recommended. Manned experiments indicate that measurements of urine excretion of endogenous creatinine hold promise for these purposes.


The use of laminar flow for obtaining germ-free mice.

Hysterectomy in a laminar-flow cabinet affords greater economy of time and effort in obtaining germ-free mice than other methods. No contamination has occurred during the surgical procedure or in the subsequent transfer of the neonates into germ-free isolators.


Halothane anaesthesia of normal and dystrophic hamsters.

Induction, carried out in a small clear-plastic box with 3-5% (v/v) halothane in 30:70 (v/v) oxygen: nitrous oxide, was quiet and rapid. Recovery was almost instantaneous. 2% halothane in the oxygen-nitrous oxide mixture was sufficient for maintenance anaesthesia. The anaesthetic mixture was given by face mask in an open circuit specially designed to function at low gas-flow rates. The halothane content of the muscle and blood after 25 min anaesthesia was estimated by gas chromatography of n-heptane extracts. The mean level (+/- s.e.m.) in blood was 22-8 +/- 2-7 mg/100 ml (n=4), and in dystrophic muscle 226 +/- 36-8 mg/100 g wet weight of tissue (n=4): there was a positive correlation (r=0-94) between them (p less than 0-02).


Control of Paraspidodera unicinata in guinea-pigs with levamisole.

Injectable levamisole was used to control Paraspidodera uncinata in guinea-pigs of both sexes, pregnant and non-pregnant, and was found to be safe and efficient at a dosage rate of 25 mg/kg bodyweight.


Spontaneous lesions and parasites of the Mongolian gerbil, Meriones unguiculatus.

Four-hundred-eighty Mongolian gerbils, Meriones unguiculatus [Uclp:(MON)], most of which were experimentally infected with filarial worms, were examined for spontaneous lesions. Previously unrecognized lesions included cutaneous squamous cell carcinoma, duodenal adenocarcinoma, malignant blue nevus, hepatic choleangiocarcinoma, malignant hemangiopericytoma of the uterus, ovarian teratoma, chronic interstitial nephritis, renal cortical retention cysts, splenic hemangiomas, and various histologic abnormalities of the lung. Previously reported lesions also seen in the present study were a malignant melanoma, adrenal cortical adenoma or carcinoma, uterine leiomyoma, sebaceous gland adenoma, hepatic lymphangioma, and renal hemangioma. Hymenolepis diminuta (Cestoda) and Tyrophagus castellani (Acarina) were accidentally recovered from experimental animals. Tritichomonas caviae and a species of Entamoeba were the most common intestinal protozoa. Tyzzer's disease, however, was clearly the most significant infectious disease of gerbils in the UCLA School of Public Health colony.


Isolation and in vitro characterization of a herpesvirus from ground squirrels (Citellus sp).

A viral agent was isolated from ground squirrel primary kidney cultures which presented a spontaneous cell layer alteration. The cultural, morphologic, and physico-chemical characteristics of the agent indicated that it belongs in the herpesvirus group. The isolate presented a narrow in vitro cell host range, growing best in marmoset monkey, owl monkey, rabbit, and hamster kidney cultures and poorly in Vero and dog fetal lung cells. The agent is readily released from infected cells, a fact which indicates that it is a cell-free virus. Good plaque formation was observed only in marmoset monkey kidney monolayers. The virus was not neutralized by antisera against other herpesviruses with the exception of a partial 1-way cross-neutralization between ground squirrel agent and Herpesvirus saguinus antisera. All these characteristics indicate that this virus is likely a new member of the herpesvirus family.


Malocclusion of the premolar and molar teeth in the guinea pig.

Malocclusions of the premolar and molar teeth of inbred Strain 2/N and Strain 13/N and outbred Dunkin-Harley guinea pigs were examined. A higher incidence of malocclusion observed in the inbred strains suggested a genetic basis for the disorder.


A natural case of Schistosoma mansoni in the chimpanzee (Pan troglodytes versus).

A spontaneous infection with Schistosoma mansoni was found in a chimpanzee (Pan troglodytes versus) recently imported from Sierra Leone, Africa. Clinical signs consisted of anemia, liver enlargement, bronchial rales, and emaciation. The primary gross pathologic lesions included a fibrotic firm nodular liver and pulmonary edema and consolidation. Histopathologic examination revealed changes similar to the experimental syndrome of Manson's schistosomiasis in the chimpanzee. The diagnosis was confirmed by the presence of the eggs and larvae of Schistosoma mansoni.


The occurrence of Mycoplasma arthritidis in the throat and middle ear of rats with chronic respiratory disease.

Twenty-three rats with chronic respiratory disease were examined for the presence of Mycoplasma arthritidis in the throat and middle ear. Samples were taken at necropsy and swabbed onto an agar medium. Morphologically typical colonies were subcultured and identified serologically. All of the rats showed evidence histopathologically of chronic respiratory disease, and typical M pulmonis colonies were isolated from 21 of 23. M arthritidis was isolated from 7 (30=) of the middle ears and 3 (13%) of the throats, confirming a previous observation of the occurrence of this organism in the middle ear of rats and also indicating it can be present in the throat.


Plasma hemoglobin determination in beagle dogs. An adaptation of the method of Crosby and Furth.

The plasma hemoglobin concentration of beagle dogs was measured following an improved bleeding technic which minimized trauma of the red cells. The benzidine reaction (benzidine dihydrochloride) was used to measure the hemoglobin present. Plasma hemoglobin values of the first 2 ml of blood collected were statistically significantly higher (P less than 0.01) than values of the next 2-3 ml of blood. Plasma hemoglobin values of normal beagles were 0.5-2.5 mg/dl in minimally hemolyzed samples. Recovery rates of up to 92% of hemoglobin added to plasma were possible with this method.


Capillary tube urinalysis for small animals.

A simple method was devised using a capillary tube to collect urine for urinalysis. This method offers the following advantages: the animal is not adversely influenced; the collection and analysis of the urine is repeatable; the amount of urine required is small; because of the simplicity of the method, the number of samples tested in a given time can be increased; and contamination with foreign material is reduced, permitting more accurate evaluation of the urinary sediments.


Technics for blood collection and intravascular infusion of reptiles.

Several methods for external sampling of blood and administration of intravascular fluids are applicable to reptilian species. This paper reviewed some of the technics that have been previously reported and introduced several new procedures applicable to snakes, turtles, alligators, crocodiles, and lizards.


The breeding and utilization of baboons for biomedical research.

The baboon (Papio cynocephalus) has been used extensively for biomedical research at the Southwest Foundation for Research and Education (SFRE) since 1958. This animal model has adapted well to captivity, has reproduced efficiently, and has proved to be very useful in many areas of medical research. Reproductive data from the SFRE baboon colony, the establishment of a breeding colony from imported animals, the present use of baboons as research models, and the predicted availability and use of these animals were discussed.


Reproductive, gestational, and newborn physiology of the chimpanzee.

The Yerkes Regional Primate Research Center has successfully bred chimpanzees since 1930. Breeding statistics for the last 6 yr and problems of fetal waste and infant mortality are presented here. Experience with a potential advantages of semi-free-ranging breeding systems are presented. This 6-yr study period also produced considerable information on gestational and newborn physiology.


The distribution of perceptual cues in English prevocalic fricatives.

Two experiments involving deletion of selected segments of syllables were undertaken to investigate the distribution of perceptual cues and the role of right-to-left coarticulation in fricative vowel monosyllables. From 12 original syllables (/f, theta, s, integral/ in combination with /i, u, a/), manipulations were made so that a group of listeners were exposed to transitionless syllables and isolated segments of syllables. Consonant and vowel recognition scores under these conditions showed that right-to-left coarticulation effects are perceptible, but do not contribute to consonant identification. The vocalic effects shown for many monosyllables were consistent with a normalization hypothesis. In agreement with previous literature, spectral cues in frication determine /s, integral/ recognition. These cues also contribute to the identification of many /f/ and /theta/ syllables.


Contextual variables related to inconsistent /s/ and /z/ production in the spontaneous speech of children.

The relationship between phonetic context and inconsistent productions of /s/ and /z/ in the spontaneous speech of three approximately three-year-old children was investigated using a nonlexically constrained segmentation, the VCnV syllable. Cn represents any number of consonants occurring between two vowels. The results indicate that of the speech segments surrounding /s/ and /z/ only the identity of consonants following these segments was significantly related to the accuracy of /s/ and /z/ production. The implications of the data for models of speech production are discussed.


Neuropsychologic function of children with severe hearing impairment.

A neuropsychologic and medical study was carried out on a selected sample of 34 hearing-impaired children aged seven to 10 years at the onset of the study. In 16 children the cause of the hearing loss was thought to be exogenous. Eight of these had evidence for organic brain dysfunction. Nine children were thought to have genetic etiologies, and in nine no cause could be determined (sporadic hearing loss). Medical examination revealed several unsuspected abnormalities, particularly visual ones. Motor and visual motor deficits were frequent among hearing-impaired children with brain damage. The Performance Scale of the Wechsler Intelligence Scale for Children, and Raven's Coloured Progressive Matrices, as well as the Paper Folding item of the Hiskey-Nebraska Test of Learning Aptitude appeared sensitive to the presence of brain damage. The mean score for the WISC Performance Scale fell within the average range for hearing children, supporting previous findings of cognitive competence of the deaf. In this sample, Hiskey-Nebraska scores tended to be lower than WISC scores. Reasons for this discrepancy were suggested and did not appear to be accounted for by brain damage. Deficits in items requiring visual memory, sequencing, and categorization were relatively prevalent but showed no etiologic predilection. They were thought to be related to the consequence of hearing loss rather than to brain damage. Difficulty with stereognosis highlighted the problem of deciding why a hearing-impaired child might fail a particular task. This difficulty suggested that failure might not indicate a deficit in the function the task was designed to measure, but rather, reliance on an inefficient strategy for success.


Self and mutual speech comprehension by deviant- and normal-speaking children.

This study was conducted to determine whether deviant-speaking children can understand their own speech productions when these productions are presented to them from an external source (tape recorder). Two groups of children with normal and deviant speech attempted to comprehend their own and one another's recorded repetitions of two matched lists of imperative sentences. Although there was a significant main effect for comprehension of high- and low-intelligibility sentences, a significant main effect for the groups' comprehension performances was not found. The results suggested that the deviant-speaking children were perceptually oriented to the standard code of the speech community rather than to their own deviant speech codes. Deficits in speech production are discussed in terms of a reduction theory of telegraphic speech. Deviant-speaking children may reduce complexity of speech output through the application of phonetic reduction rules.


Localization of two noise sources overlapping in time.

The accuracy of localization of two independent, wide-band noise sources, overlapping in time, was measured. Subjects given preliminary practice had little difficulty in localizing when sources separated by 55 degrees were located in front of them or in back of them, with one source 10 degrees from the midline. But when sources were at the side of the subject, perception that there were two sources present tended to improve significantly as time between onset of the sounds was increased to 100 msec. Once a sound was perceived to be present, it was localized with fairly high accuracy.


Reduction of stuttering frequency using analog electromyographic feedback.

Three stutterers were taught to reduce resting muscle activity by using analog electromyographic feedback from four sites over different muscle groups. They were then trained to reduce muscle activity prior to uttering selected sentences. A functional analysis was performed to determine the relationship between the decrease in stuttering frequency on initial phonemes and the reduction of electrical activity at each muscle site. Subjects demonstrated different responses to training. One subject's greatest decrease in stuttering frequency was associated with muscle activity training at a lip site. A second subject's greatest decrease in stuttering was associated with training at a laryngeal site. A third subject's greatest decreases in stuttering were with both lip and laryngeal site training. Following these demonstrations that stuttering could be controlled with electromyographic feedback, a practical management program was designed for a fourth stutterer. Feedback training to reduce electromyographic activity when paired with speech resulted in elimination of stuttering in two monitored situations, conversations and telephone calls. Probes indicated the stuttering continued to be markedly reduced in all situations nine months after treatment.


Voice onset time, frication, and aspiration in word-initial consonant clusters.

The voice onset time (VOT) and the duration of the burst of frication noise at the release of a plosive consonant were measured from spectrograms of word-initial consonant clusters. Mean data from three speakers reading English words in a sentence frame indicated that the VOT changed as a function of the place of articulation of the plosive and as a function of the identity of the following vowel or sonorant consonant. Burst durations varied in a similar way such that the remaining interval of aspiration in /p, t, k/ was nearly the same duration in comparable phonetic environments. The VOT was longer before sonorants and high vowels than before mid- and low vowels. Aspiration was also seen in an /s/-sonorant cluster. To explain these regularities, production strategies and perceptual cues to a voicing decision for English plosives are considered. Variations in VOT are explained in terms of articulatory mechanisms, perceptual constraints, and phonological rules. Some VOT data obtained from a connected discourse were also analyzed and organized into a set of rules for predicting voice onset time in any sentence context.


Vertical laryngeal position during continuous and discrete vocal frequency change.

Six young adult male subjects produced sustained phonation throughout their vocal frequency ranges: first, in a glissando or continuous frequency change maneuver, and second, in discrete intervals at separate trials. Measures of intrinsic and extrinsic laryngeal muscle activity and vertical laryngeal position were related to voice fundamental frequency in the two conditions. Each subject consistently positioned his larynx at a resting level when he was instructed to relax or when he was not performing experimental tasks. All larynx positions during experimental tasks were measured as deviations from this resting level. Subjects showed a close correspondence between their vertical laryngeal positions and voice frequencies--more so for the glissando maneuver than for changes in discrete frequency tasks. In general, subjects lowered their larynges from the resting position for low-frequency phonation and raised their larynges for higher fundamental frequencies. Absolute larynx position for the same frequency was quite varied both within and between subjects. Vertical laryngeal position during phonation most often was directly related to the activity of the thyrohyoid and sternothyroid muscles. Neither vertical laryngeal movement nor intrinsic laryngeal activity showed any pattern of relationship to changes between modal and falsetto voice registers.


The effect of combining low- and high-frequency passbands on consonant recognition in the hearing impaired.

A comparison was made of the effect on consonant-recognition scores when a low-frequency passband and a high-frequency passband were presented to either the same ear or opposite ears of hearing-impaired subjects. The Fairbanks Rhyme Test was filtered into two bands-240-480 Hz (low band) and 1020-2040 Hz (high band). The high band was presented at 10 dB re threshold at 1500 Hz to the better ear of six subjects with moderate to severe sensorineural hearing losses. The low band was presented to the same (ear receiving high band) or the opposite ear at levels of 10, 30, or 50 dB SL re threshold at 360 Hz in that ear. When the low band and high band were added to the same ear, there was little change in the consonant-recognition score, but, when presented to opposite ears, there was a significant increase in the score, at each of the three sensation levels.


Comparison of glottal area changes as measured from ultrahigh-speed photographs and photoelectric glottographs.

To determine the relationship of information on glottal area function provided by deviations sensed by the photoelectric glottograph to that derived from a frame-by-frame analysis of ultrahigh-speed photographic film, simultaneous photographic and glottographic recordings were obtained from five subjects. From the investigation, the following results were obtained: (1) the measurements of the light deviations sensed by the photoelectric glottograph during laryngeal vibrations produced curves that approximated those developed from photographic film frame-by-frame measurements of the visual image in vocal fry, modal, and falsetto voice registers, and (2) the Fourier coefficients of the compared data indicated that there was no significant difference between the curves.


Rhythm and syllable timing in phrase level stress patterning.

The rhythm of syllables in repetitions of a phrase was measured with a finger-tapping task. These rhythm measurements were shown to vary with phrase level stress patterning. However, this relationship was not invariant. Acoustic measurements of the time between syllables showed stress pattern relationships similar to those observed in the rhythm-tapping task. The temporal differences between stress patterns appear to be (1) evident even when acoustic measurements exclude syllable duration, (2) significant even at a fast speaking rate, and (3) variable between speakers.


A comparison of pure-tone thresholds as measured by delayed feedback audiometry, electrodermal response audiometry, and voluntary response audiometry.

One hundred unselected patients seen for medical-legal evaluation were tested for pure-tone thresholds by delayed feedback audiometry (DFA), electrodermal response audiometry (EDRA), and voluntary response audiometry (VRA). The EDRA method was successful in 73% of the patients while the DFA method was successful in 88% of the patients. Eighty-six percent of the DFA thresholds obtained were within 10 dB of the patients' VRA thresholds. When both DFA and EDRA were successful, 88% of the DFA thresholds were within 10 dB of the EDRA thresholds. Ninety-six percent of the EDRA thresholds obtained were within 10 dB of the patients' VRA thresholds. Although DFA is not as precise in predicting threshold as is EDRA, it is successful in a significantly greater number of patients than is EDRA and is a useful clinical tool in medical-legal evaluation for hearing loss.


Pronoun assessment: a free speech technique.

A study of the free speech pronoun usage of 15 normal and 15 language-delayed children showed that it is possible to distinguish between children at five different levels of language development by considering linguistically relevant pronoun properties. The discriminating measure considered the frequency of pronoun types as a percentage of the child's total utterances. It is suggested that eliciting child utterances in a free play situation with the principal caregiver provides a good language sample and has potential as a diagnostic method.


Identification and discrimination of vowel-consonant syllables in listeners with sensorineural hearing loss.

The speech encoding ability of eight persons with sensorineural hearing loss and three persons with normal hearing was studied in identification and discrimination paradigms. In the identification task a feature analysis of transmitted information for VC syllables was used to study encoding ability. Transmitted information was reduced from normal for persons with hearing loss, indicating a loss of ability to encode consonants. In the discrimination task coding ability was studied by measuring reaction times (RTs) for "same" and "different" decisions. The RSs for individuals with impaired hearing were found to be significantly different from those subjects with normal hearing. The trend was for faster "same" than "different" RTs among the normal subjects and faster "different" than "same" RTs among the hearing-impaired persons. The results are interpreted as indicating that the two groups of subjects used different processing modes in discriminating between pairs of phonemes.


Residual hearing and speech production in deaf children.

Residual hearing, phoneme recognition, speech production errors, and selected background variables were examined in 40 congenitally deaf children of normal intelligence who had no apparent anomalies other than deafness, in an effort to identify factors most closely associated with speech intelligibility. Mean intelligibility of the recorded speech of the children, to inexperienced listerners, was 18.7%, corresponding closely with results of previous studies. Scores on the total and some portions of the phoneme recognition test showed significant correlations with both phoneme production and speech intelligibility. The correlation between phoneme production errors and intelligibility was -0.80. A sizable proportion of the dispersion could be accounted for by certain prosodic errors, such as those resulting from improper phonatory control. Errors of place of articulation and voicing remained in essentially the same proportion for all speakers. Errors of manner and combined place and manner of articulation showed a slight systematic decrease from the poorest to the best speakers. Omissions decreased sharply, but not systematically. Vowel errors showed the most marked and systematic decrease as intelligibility improved. Children of deaf parents were poorer in phoneme recognition and in speech intelligibility than children with comparable residual hearing but with hearing parents.


Dynamic palatometry.

A computer-based instrumental system is described for continuous palatometry. Thin pseudopalatal plates (approximately 0.2 mm) with embedded electrodes are used to detect linguapalatal contact during speech articulation. Geometric configurations of such contacts are then derived and displayed to reveal articulatory characteristics.


Cardiovascular fitness in a selected group of dentists.

Thirty-three dentists were studied as part of an exercise rehabilitation clinic in order to evaluate their cardiovascular capacity and coronary prone risk factors. Measurements were made of their physical work capacity, predicted maximal oxygen uptake, fatness, serum lipids and uric acid levels, pulmonary peak flow rates and personality Type A or B. The group as a whole exhibited a moderately high level of fitness and a very active life style which probably reflected their presence at a clinic of this type. Cardiovascular fitness varibles increased with age. This increase may be due to a need and desire on the part of the dentists to maintain their physical fitness as they become older. This need for improved self image may also be a factor in their joining an exercise rehabilitation clinic.


Investigation into hamstring strains: the case of the hybrid muscle.

Past research on hamstring strains indicated an imbalance in leg strength as a cause of hamstring strains. No theory has been put forth to explain why the strength imbalance would cause strain. Investigation on cadavers of the muscular attachment of the short head of the biceps femoris indicated the varied attachment of this muscle to the linea aspera. It is theorized that an extensive attachment to the linea aspara and a strength imbalance would cause hamstring strains.


Transovarial transmission of arboviruses by mosquitoes: a review.

One interesting aspect of mosquito-borne arboviruses is their endemic persistence, espeically during adverse climatic conditions in the temperate zones. The hypothesis that transovarial transmission of alpha- and flaviviruses by their respective mosquito vectors could serve as an overwintering mechanism has been proposed; however, experimental data in support of this hypothesis are not very convincing. Recently, some of the California encephalitis group arboviruses have been shown to be transmitted transovarially by Aedes species mosquitoes, and studies indicate that this mechanism contributes to the natural maintenance cycle of these viruses. Finally, consideration is given to the possibility that transovarial transmission may be unique to the California encephalitis group arboviruses and may be related to their association with a vector that overwinters in the egg stage of its life cycle.


Mosquito-borne viruses in Finland.

Inkoo virus, the Finnish representative of the California group, was isolated from a pool of Aedes communis/punctor. It is distinguishable from Tahyna, California encephalitis, Trivittatus and Melao viruses, but seems to be antigenically related to the Jamestown Canyon virus. The prevalence of Inkoo antibodies increases towards the north in both human beings (16% to 69%) and cows (37% to 88%). Inkoo antibodies are common also in other mammals of large size (reindeer, moose, foxes), less frequent in snow hares, rare in hazel grouse and not detected in other birds and small mammals. Some show hare serum samples react with Inkoo virus only in the hemmaglutination inhibition test suggesting the existence of another California group virus in Finland. In addition, antibodies against some other mosquito-borne viruses have been found in Finland. A Batai virus epizootic among cows may have occured in the early 1960's in southern coastal Finland, and some serological data point to the existence of alphaviruses in Finland. The overwintering mechanism of the Finnish mosquito-borne viruses is still unsolved.


Ecology of tick-borne viruses in colonies of birds in the USSR.

During 1969--1974, 66,000 argasid and ixodid ticks from bird colonies in different parts of the USSR were studied. 247 strains of 8 different viruses were isolated. West Nile, Baku and Caspiy viruses were found from argasid ticks in the Caucasus and Middle Asia whereas ixodid ticks from seabird colonies in the North of the Far East and in the European part of the country yielded Tyuleniy, Zaliv Terpenya, Okhotskiy, Sakhalin and Paramushir viruses. The implications of the findings in the ecology of arboviruses is discussed.


The damaging action of cellular immunity in flavivirus infections of mice.

The development of acute infections caused by different flaviviruses was studied in immunosuppressed inbred and non-inbred mice. Cyclophosphamide treatment of challenged animals resulted in an increase of the mean survival time by 24--144 hours in some but not all virus-mouse strain combinations. The transient protective action of cyclophosphamide was not due to suppression of the reproduction of tick-borne encephalitis (TBE) or dengue 2 (D2) virus in the brains of mice. In TBE or D2 infections of immunosuppressed mice the clinical signs of central nervous system lesions seemed to be associated with the development of cellular immunity measured by the splenobyte migration inhibition test. The transfer of sensitized splenocytes in immunosuppressed animals, challenged with TBE or D2 virus, shortened the incubation period. These results suggest that cellular immunity may have a damaging effect in acute flavivirus infections in mice, and also that the immunopathological response varies considerably in different strains of inbred mice.


Interference with the glycosylation of Semliki Forest virus proteins.

It has been shown that under defined conditions the multiplication of SFV can be inhibited by specific interference with the production of viral glycoproteins. These conditions are: a) Either 0.2 mM dGlc or 2 mM glucosamine in glucose-containing medium, b) lack of any sugar or energy source in the culture medium, c) pyruvate as energy source, late in the infectious cycle. Under these conditions underglycosylated glycoproteins occur, which cannot be used to form physical or infectious particles. It is not yet clear whether the appearance of a heterogeneous population of molecules in the molecular weight range between 50 and 63,000 is due exclusively to different lengths of the carbohydrate side chains, or also due to wrong splitting or partial degradation of the precursor molecules by cellular proteases. Glucosamine seems to act via the accumulation of UDP-N-acetylglucosamine (or a derivative of it), while dGlc is metabolized along the pathway of mannose and acts mainly as an antimetabolite of mannose.


Defective particles in alphavirus infections.

This article summarizes our studies with defective-interfering particles of Sindbis virus obtained by high multiplicity passaging of the virus in BHK cells. Cells infected with these defective passages accumulate a species of RNA (20S) at the expense of 26S RNA--the mRNA coding for the viral structural proteins. Although the structure of the RNA in defective particles remains undefined, our studies of replicative forms and replicative intermediates suggest that it is larger than the intracellular 20S RNA. The defective particles are unable to synthesize detectable amounts of viral structural proteins when they infect a cell in the absence of standard virus and they do not contribute to the stimulation of intracellular viral RNA synthesis. We have proposed a model for the mechanism of interference by these defective particles in which standard and defective RNAs compete for a limited amount of viral-specific replicase.


Polysomes and initiation complexes in vitro induced by Semliki Forest virus 42S and 26S RNA.

Semliki Forest virus 42S and 26S RNA induce the formation of polysomes when translated in vitro in cell-free systems. After analysis on sucrose gradients the polysomal structures, containing prelabelled RNA and nascent peptide chains labelled with [35S]methionine, had sedimentation values from 100 to 200S in the case of 26S RNA and from 150 to over 250S with 42S RNA. After incubation in the presence of inhibitors of elongation 26S RNA was found in initiation complexes sedimenting at about 80S. Under identical conditions 42S RNA had a heterogenous sedimentation pattern, being attached to complexes sedimenting even faster than 250S. These structures, however, fulfilled the criteria of initiation complexes suggesting that there were more than one ribosome attached to each 42S RNA under conditions where 26S RNA bound only one.


The basis of arbovirus classification.

The biologically defined set of arboviruses contains well over 300 separate viruses which have been subdivided into some 40 serological groups on the basis of antigenic cross-reactivity. More than three quarters of all arboviruses can now bw placed into one of the following five major taxonomic genera based upon the fundamental properties of the virion: alphavirus, flavivirus, orbivirus, rhadovirus, bunyavirus. There are 20 alphaviruses, representing serological Group A, and 57 flaviviruses in serological Group B; these two genera fall into the familty Togaviridae. The 40 orbiviruses, in the family Reoviridae, include some 8 serological groups, and the 8 rhabdoviruses, in the family Rhabdoviridae include another 3 groups. About 160 bunyaviruses, family Bunyaviridae, are divisible into 20 serological groups, 10 of which show intra-group cross-reactions in the Bunyamwera supergroup. One arbovirus contains DNA, namely African swine fever virus; this is classified as an Iridovirus, or icosahedral cytoplasmic deoxyvirus. Nodamura virus, which has been classified as a picornavirus, must be reclassified on the evidence that it possesses a divided genome. A number of arboviruses remain unclassified in taxonomic terms. The absence of arbovirus representatives in several major genera, such as the adenoviruses and the myxoviruses is of no interest.


Tick-borne viruses in Norway.

The purpose of the investigation was to chart the existence and extent of arboviruses in Norway and provide information on their possible significance. Virus isolations have been attempted from ticks (I. ricinus, I. trianguliceps, I. uriae) and host animal blood from selected locations. Serological screenings have been performed with bird, small mammal, cattle and human blood. Five virus strians have been identified to date. Three of them are related to Uukuniemi virus group. Two identical strains from I. uriae demonstrate the morphology of coronaviruses and no antigenic relationship to major arbovirus groups. Within the distribution areas of I. ricinus, antibodies to tick-borne encephalitis virus are prevalent in cattle. Antibodies to Uukuniemi viruses are found in passerine birds, small mammals, cattle and man. Antibodies to the coronavirus like agents have been demonstrated in seabirds.


[Optimum perfusion pressure, renal resistance and oxygen consumption of kidney in hypothermic pulsating perfusion].

36 dog kidneys were perfused with different perfusion pressures (between 15 and 60 mm Hg) for 72 hrs and then transplanted. Hypothermic human albumin was the perfusion fluid. Kidneys perfused with a flow rate of 0.8 ml/g/min (21 mm Hg mean perfusion pressure) showed the smallest increase in kidney weight and the best function after transplantation. Renal vascular resistance was independent of the level of the perfusion pressure and renal oxygen consumption was independent of the applied flow rate.


[Effect of pO2 in perfusate on metabolism of preserved dog kidneys].

In 48 canine kidneys submitted to an ischemia of 2 min duration normal cortical ATP values with a nearly unchanged content of total adenine nucleotides (SAN) were resumed by a five minute gravity perfusion. During the following 24 hours of low flow perfusion at 6 degrees C the extent of preservation of ATP and SAN correlated with the arterial oxygen pressure of the perfusate.


[Changes in transplantation antigens of the dog due to cerebral ischemia and their demonstration using the cytotoxic test].

Experiments were performed on 19 mongrel dogs. Changes of transplantation antigens by anesthesia and by brain ischemia were identified in cytotoxic tests. Brain ischemia was responsible for the significant alterations in 5 antigens, anesthesia alone induced significant changes in 3 antigens.


[Treatment of pseudomonas infection following burn injuries with specific antitoxic Ig-therapy].

The mortality rate of mice after standardized Pseudomonas infection was increased by preinjection of a sublethal dose of burn toxin. This effect was eliminated by a specific antitoxic Ig. After a sublethal burn followed by infection, 60% of the animals died, while treatment with specific Ig reduced the mortality rate to 3.3%. This might be a new way to improve the treatment of severely burned patients.


[Experimental use of a q-switched YAQ high-performance laser as a surgical tool].

A q-switched YAG-laser has been investigated as an "optical knife". It was possible to cut rat liver without bleeding but there was no influence of the repetition frequency on the cutting effect. Otherwise, the width of the necrotic zone could be changed evidently more by using the q-switch-technique than by using a cw-laser. First experiments with pig liver showed, that larger vessels can be cut without bleeding by using laser beams as an "optical tool".


[Animal experiment studies on the effect of vitamin A on cortisol-induced wound healing disorders].

In animal experiments on rats we could show that wound healing, inhibited by cortison can be normalized by vitamin A administration. The reason for this behaviour is assumed to be an antagonistic effect of cortison and vit. A via the inflammatory phase on the amount of newly formed collagen. The increase of the alpha 1 and alpha 2 globulin fraction and the decrease of the albumin fraction in the serum caused by vitamin A seems to indicate this fact as well as the pronounced leucocyte depression under cortisol treatment.


[Lowering of serum bilirubin following experimental ligation of the bile duct. Affinity-chromatography binding of bilirubin to albumin conjugated with agarose].

Principle and procedure of a new method in the treatment of experimental hyperbilirubinemia for removing protein-bound, not dialyzable substances from blood by extracorporeal hemoperfusion are described. In six out of eight experiments a decrease of serum bilirubin levels between 11 and 36% has been accomplished. Changes in hemograms are reported and correlations between serum bilirubin value, amount bilirubin bound by the agarose beads and bilirubin clearance rate are discussed.


[Significance of intravascular coagulation and acidosis on increase of pulmonary vascular resistance following trauma and hemorrhagic shock].

24 anesthetized mongrel dogs are subjected to a standardized trauma followed by a hypotonic hemorrhagic shock. Compared with the control group (n equals 8) prophylactic treatment with heparin in the second group (n equals 8) reduces the rise of pulmonary vascular resistance only insignificantly. The correction of the metabolic acidosis with Tris does not prevent a rise of PVR in third group (n equals 8).


[Fibrinogen metabolism and distribution in tourniquet-trauma].

The distribution and turn-over of 131J-labelled fibrinogen was studied in traumatized rats. Tourniquet-trauma resulted in a pronounced accumulation of labelled fibrinogen in the traumatized region. The accumulation was at the expense of all nontraumatized-tissue. In controls there was a parallel decline of total-body-activity and plasmaactivity. The T.B.A. of traumatized animals showed a similar disapprearance-rate, while there was a pronounced reduction of circulating labelled fibrinogen.


[Controlled hypothermia of ischemic extremities for the prevention of tourniquet shock].

The tourniquet-shock in dogs was produced after recirculation of ischemically stressed bilateral hind limbs. 4 of 7 dogs died within 5 hours after release of the tourniquets. The cause of heart failure could be defined by hypercaliaemia, metabolic acidosis and hemoconcentration. The development of tourniquet-shock could be suppressed by hypothermic preservation of the ischemic extremities.


[Effect of glucagon on changes of carbohydrate metabolism in experimental hemorrhagic shock].

The behaviour of venous blood glucose, lactate and pyruvate concentration was tested in experimental shock, caused by bleeding in rabbits. The animals of one group were retransfused after 1.5 hours hypotension of 40 mm Hg. The animals of another group were left with a total blood removal of 2% body weight. We found a significantly higher blood sugar reaction in the longer surviving animals of the group in comparison to the ones, which died early. A single or repeated intravenous application of 70/1000 mg glucagon was not followed by a statistically visible change of blood sugar-, lactate- and pyruvate values in shock versus the control group. In spite of pronounced hypovolemia 20 of 22 animals, treated with glucagon, showed an increase of blood pressure by 20 mm Hg and of cardial frequency, especially after the first injection over a period of 10 minutes with decreasing tendency in the further course of shock.


[Histological and biochemical changes in the lung in relation to survival time following femoral fracture in the dog].

Following an experimentally applied fracture of the upper limb fat embolism can be demonstrated in the lungs. By quantitative histological evaluation and biochemical lipid analysis a definite correlation can be observed between the amount of fat in the lungs and the time interval that had elapsed between fracture and death of the animals. More fat is to found in lungs histologically as well as biochemically in those animals, in which the time interval was shorter (165 minutes) than in those which survived for a longer period of time (168 hours). The electronmicroscopic morphometric examination turned out an increased volume of the interstitium 72 hours after the fracture.


[Surgical treatment of Sipple's syndrome (author's transl].

Sipple's syndrome (bilateral phaeochromocytoma and medullary thyroid carcinoma) is a multiple endocrinopathy with a familial occurrence. The medullary thyroid carcinoma develops from the intrathyroidal C-cells. Radioimmunological analysis of serum calcitonin, basally or after calcium infusion, discloses the tumor also in asymptomatic members of the families. The patients are treated in two sessions. In the first a bilateral adrenalectomy is performed and in the second a total thyroidectomy with modified neck dissection. Major preoperative diagnostic procedures as angiograms and phlebograms as well as the bilateral adrenalectomy must be preceded by pre-treatment with alpha- and beta- receptorblocking substances.


[Calcitonin determination as a possibility for the evaluation of surgical result in medullary thyroid carcinoma (C-cell carcinoma)].

In 4 patients with medullary thyroid carcinoma serum calcitonin was measured before and after surgical treatment. In 3 cases serum CT was normalized after operation, whereas one case showed persisting hypercalcitonism as a hint for metastasation. Selective venous catheterization with CT-determination was useful for lacalizing metastases.


[Electronic volume analysis of cell nuclei in the gastric mucosa].

A trial was conducted for mechanical and objective analysis of gastric mucosal specimen concerning suspicion of malignancy by means of electronic nuclear volume analysis. 16 specimen of normal and 10 specimen of malignant gastric mucosa were investigated. The mean nuclear volume was 37.3 mu3 in normal and 54.8 mu3 in carcinomatous mucosa. The difference with p less than 0.00005 is highly significant.


[Correlation of blood-chemistry changes and development of cancer in experimental tumor induction in the colon of rats].

The changes in the blood cell count and in the blood chemistry (fibrinogen in the plasma, Fe and Cu in the serum) that we have found, were only seen in a late tumor state. This is also valid for the serum aldolase activity, which is said to be a screening test for a recurrency of a tumor.


[O2 pressure on liver surface following portacaval anastomosis and administration of vasoactive substances in dogs with normal livers].

1) Following acute portocaval anastomosis in healthy dog liver tissue - pO2 drops by 23%, an extent regulary occuring in hour long laparotomy. 2) Intravenous octapressin lowers splanchnic blood flow, concomitantly liver blood-flow and tissue -pO2 is decreased. 3) In contrast to octapressin orciprenalin improves liver blood-flow and tissue-pO2. 4) By shunting of arterial blood through the gut norepinephrine causes a rapid and lasting elevation of liver tissue-pO2.


[Effect of antrectomy of total gastrectomy on calcium-induced gastric secretion and gastrin liberation in man].

These studies show that calcium stimulates gastric secretion and gastrin release in healthy individuals and duodenal ulcer patients. After antrectomy calcium still stimulates gastric secretion without affecting basal serum gastrin concentration. After total gastrectomy serum gastrin levels are decreased; hypercalcemia results in a small but definite release of gastrin from extraantral sites.


[Mechanism for the liberation of duodenal gastrin in the dog].

The mechanisms of duodenal gastrin release were studied in 13 mongrel dogs after selective mucosal antrectomy: Vagal stimulation with insulin and local perfusion with acetylcholine at pH 7 resulted in a significant increase of the serum gastrin level taken from the pancreatico-duodenal vein. No significant amounts were detected after vagal stimulation with 2-deoxy-d-glucose, local perfusion with acetylcholin at pH 1, 5 nor after duodenal distension with 20, 40 and 120 cm water.


[Effects of cyclic AMP and urecholine on gastric secretion in the dog].

The influence of cyclic AMP on gastrin release from the canine antrum was investigated by a direct in vivo method. After removal of spleen, gastric corpus, pancreas and intestine an antral pouch was consecutively perfused with dibutyryl cyclic AMP, papaverin and bethanechol-HCl using a branch of the left gastroepiploic artery. A relevant rise of gastrin in portal blood was only observed during perfusion of bethanechol chloride. Thus cyclic AMP does not release gastrin from the canine antrum.


[Serum gastrin level following duodenal and gastric stimulation with acetylcholine in the dog].

Before and during instillation of a solution of 1% acetylcholine into the duodenum and stomach of 13 mongrel dogs serum gastrin levels were measured at 5 min intervals. After gastric stimulation a sustained rise of serum gastrin concentration was observed. After duodenal stimulation gastrin levels rose only slightly. The multiple factors responsible for this phenomenon necessitate further investigations.


[Clinical and experimental studies on the transplantation of preserved tendons].

The tensile strength of preserved tendons was studied in relation with duration and preserving process. Cialite preserved cow-tendons were implanted in rear limbs of rabbit. After 5, 7 and 9 months the transplants could still be identified. They were covered by unreactive fibrous connective tissue, where by adjustant to the connective tissue the transplant was replaced by multicellular growing tissue. In clinical practice preserved tendons were successfully used for ligament-plastic. It is reported on the possibility of use and the results.


[Extragastric gastrin liberation. Studies on patients following gastrectomy and duodenopancreatectomy].

28 investigations were performed in control patients with no gastric disease (n equals 10), in patients after total gastrectomy (n equals 10) and in patients after duodenopancreatectomy (n equals 8). We measured the serum gastrin concentrations in the fasting state and after the ingestion of a test meal. The results indicate that more than 60% of the gastrin activity is released from extragastric sites and in addition, it is supposed that about 20% are released from extragastric and extraduodenal sites.


[Animal experiments on absorption and blood circulation in a mechanical ileus of the small intestine].

Using the perfusion technique the absorption of glucose, water and sodium was studied in the obstructed bowel. When the obstruction was reversed, the decreased absorption of glucose normalized after 24 hrs., of water and sodium after 36 hrs. The intraluminal pressure does not alter the capillary circulation during obstruction. Histologically an edema of the bowel wall and impaired venous flow was observed. In electronmicroscopic studies no morphological changes could be seen.


[Animal experiments on the prevention of acute gastric mucosa erosions using vitamin A].

A significant reduction of vitamin A serum levels was observed in rats which underwent a hypoxic stress. The number of gastric ulcerations secondary to stress can be significantly reduced by 125 000 to 250 000 I. E. of vitamin A applicated parenterally prior or with the onset of stress. Consequently a prophylaxis of stress ulcerations appears to be possible by application of vitamin A.


[Kinetics of bile acid in jejuno-ileal bypass].

The influence of jejunoileal bypass on bile salt kinetics and lithogenity of bile was investigated in 9 German shephard dogs. Total bile acid pool decreased 92% from initial values, bile acid turnover rate was enhanced markedly. High relative biliary cholesterol concentration lead to an increase of lithogenity of the bile.


[Electric and mechanic gastric activity under insulin, penta-gastrin, carbachol and food ingestion in the wakeful dog].

The effect of insulin, pentagastrin, carbachol and feeding on the electrical and mechanical activity of the stomach was examined in the conscious dog. In these experiments vagal stimulation, a gastric hormone, a parasympathetic agent and distention elecited a similar stimulation of electrical and mechanical activity. The activation occurred in case of insulin only after sufficient lowering of the blood glucose level, in case of the other tested stimulants after a few minutes.


[Behavior of intestinal motility and serum gastrin level during prostaglandin administration in acute mechanical ileus of the rabbit].

In 29 rabbits the action of PGF2 alpha and PGE2 was compared with prostigmine in a mechanical ileus model. PGE2 produces no therapeutical effect. PGF2 alpha delivered a significant increase of intraluminal intestinal pressure and of the amplitudes of peristalsis, lasting for about 5 minutes, whereas prostigmine made a long lasting significant enlargment of the amplitudes of peristalsis without any modification of intraluminal pressure. Serum gastrin levels increased after application of PGE2 and PGF2 alpha and remained constant after prostigmine. A possible way of action of PG's in the gastrointestinal tract is discussed, based on experiments concerning PG-application after different periods of time.


[Experiences with an electrically conducting plastic electrode for transient cardiac pacing in infants].

An esophageal balloon catheter is equipped with an electrical conductive rubber electrode. Cardiac pacing by battery-powered external pace-makers with low output voltage was successfull in babies and young children.


[A new model for reflux prevention following distal and total stomach resection].

By means of a short isoperistaltic invagination of a small bowel segment a valve mechanism has been developed experimentally. After complete or partial gastric resection (B II) reflux of alkaline intestinal secretion could be prevented. Even under extreme pathological conditions like head down position and external compression normal valve function has been achieved.


[Construction of a neoesophagus using lyophilized dura. Animal experiment in dogs].

The experiments have proven the feasibility of bridging short oesophageal defects as well as longer ones with lyophilized dura. By means of a two-stage-operation respectively a combined homologous-alloplastik oesophageal prosthesis the risk of insufficiency of anastomoses may be minimized. Thus its clinical application seems worthy of consideration.


[Experimental partial reconstruction of the esophagus using a free transplant of the small intestine].

Partial replacement of the esophagus was carried out in 20 dogs by means of free transplantation of a small bowel segment with vascular anastomosis to the aorta and v. azygos magna. Intestinal electromyography was used for vitality control in all cases and turned out reliable results. 15% of the cases showed thrombosis of the venous anastomosis with intestinal necrosis.


[Stabilization of a small intestine invagination valve using Kock's method. Animal experiment].

A Thiry-vella loop was performed in 37 dogs and 147 intussescepted intestinal valves were constructed and tested on their stability. Stabilisation of the valve through a nylonnet pulled through the mesenterium without destroying the vessels and fixed between the serosal layers of the valve with seromuscular silk sutures has been proved to be the best method.


[Continent colostomy through magnetic closure in animal experiments on dogs].

In dog experiments a continent colostomy be means of magnetic occlusion has been developed. Around a terminal anus praeter a silicon-coated ringmagnet was placed between muscular fascia and subcutaneous fascia. The colon was pulled through the lumen of the ring and sutured to the skin. There has been a primary wound healing. There was no leakage of gas and faeces beneath the magnetic cap, thus providing an excellent closure of the colostomy. After removal of the cap spontaneous defecation took place.