Given an abstract, generate a keyword (a noun phrase) that best describes the focus or contribution of the paper. Such keywords can be directly from the given abstract or outside it.
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Question: Abstract: The amount and sources of T3 associated with high affinity, low capacity cellular nuclear receptors in brown adipose tissue (BAT) have been estimated by in vivo pulse-labeling techniques. Maximal binding capacity was measured by in vivo saturation analysis. Nuclear receptor occupancy at endogenous levels of T3 and T4 in euthyroid rats was estimated from the equilibrium nuclear to serum ratio of tracer T3, and the locally generated nuclear T3 to serum T4 ratio after injecting tracer T3 and T4. These ratios were multiplied, respectively, by the endogenous concentrations of T3 and T4 as measured by RIA. The maximal binding capacity was 0.65 ng T3/mg DNA, and saturation was 71%. Fifty-five percent of the nuclear T3 was generated locally, and 45% was derived from circulating T3. BAT is, hence, comparable to the liver in number of receptors (approximately 5000/cell) and to the pituitary with regard to saturation and relative contributions of locally generated T3 and plasma T3 to nuclear T3. These results suggest that BAT may be an important target for thyroid hormones and, along with other data, that alterations in the activity of the type II 5'-deiodinase of this tissue may influence the saturation of nuclear T3 receptors.

Answer: Animal


Question: Abstract: Limping is never normal, and few parents tolerate the problem long before seeking medical consultation. However, the conditions that may produce a limp are legion and run the gamut from a stone in the shoe to the first manifestation of malignant neoplasm or chronic renal disease. As a consequence, one must have an orderly approach to diagnosis. Many of the problems that cause the child to limp are presented, but this article is concerned with an overview of the problem, differential diagnosis, and suggested steps in evaluating the child who limps.

Answer: Child


Question: Abstract: The influence of serotonin (5-hydroxytryptamine) on human detrusor and on pig detrusor, trigone, bladder neck and urethral smooth muscle was explored in a series of in vitro experiments. Serotonin evoked a dose-dependent and reversible contraction of the detrusor. The reverse response was triggered in trigone, bladder neck and urethral smooth muscle--a dose-dependent and reversible relaxation. The maximum amplitude of this relaxation was 85 +/- 15% of the relaxation produced by electrical nerve stimulation. The effect of serotonin was unaltered by blockade of ganglia, alpha- and beta-adrenergic receptors, cholinergic receptors and prostaglandin synthesis. The serotonin antagonists ketanserin, methysergide and cyproheptadine partly inhibited the effect of serotonin. The antagonism differed in potency on strips of different origin. The antagonists were ineffective or minimally effective in blocking responses to nerve stimulation. The effect of serotonin was probably mediated by specific serotonin receptors different from the serotonin-S2-receptors predominating in vascular smooth muscle. Serotonin is a potential neurotransmitter in lower urinary tract smooth muscle, but its importance in micturition physiology and pathophysiology is unknown.

Answer:
Animal


