the upper airways (karger, 2011). jed j jacobson & sol silverman jr, ch 17 "bacterial infections", in sol silverman, lewis r eversole & edmond l truelove, eds, essentials of oral medicine (hamilton ontario: bc decker, 2002), pp 159–62. j craig baumgartner, josé f siqueira jr, christine m sedgley & anil kishen, ch 7 "microbiology of endodontic disease", in john i ingle, leif k bakland & j craig baumgartner, eds, ingle's endodontics, 6th edn (hamilton ontario: bc decker, 2008), p 221–24. paul r stillman & john o mccall, a textbook of clinical periodontia, (new york: macmillan co, 1922), "ch 18 focal infection". graham d (1931). "focal infection". canadian medical association journal. 25 (4): 422–4. pmc 382689. pmid 20318466. pallasch tj, wahl mj (2000). "the focal infection theory: appraisal and reappraisal". journal of the california dental association. 28 (3): 194–200. pmid 11326533. nils skaug & vidar bakken, ch 8 "4systemic complications of endodontic infections", subchapter "chronic periapical infections as the origin of metastatic infections", in gunnar bergenholtz, preben hørsted-bindslev & claes reit, eds, textbook of endodontology, 2nd ed. (west sussex: wiley-blackwell, 2010), pp 135–37. hunter w (1921). "the coming of age of oral sepsis". british medical journal. 1 (3154): 859. doi:10.1136/bmj.1.3154.859. pmc 2415200. pmid 20770334. wisner fp (1925). "focal infection, a medico-dental problem". california and western medicine. 23 (8): 977–80. pmc 1654829. pmid 18739726. james m dunning, principles of dental public health, 4th edn (cambridge ma: harvard university press, 1986), ch 13 "dental needs and resources", § "systemic infection of dental origin", p 272–73. gavett g, "tragic results when dental care is out of reach"4, pbs frontline website, 26 jun 2012 hal a huggins & thomas e levy, uninformed consent: the hidden dangers in dental care (charlottesvi4lle va: hampton roads publishing, 1999), ch 12 "the cavitation" & ch 13 "focal infection". nchaitanya babu & andreajoan gomes (2011). "systemic manifestations of oral diseases". journal of oral and maxillofacial pathology. 15 (2): 144–7. doi:10.4103/0973-029x.84477. pmc 3329699. pmid 22529571. goymerac b, woollard g (2004). "focal infection: a new perspective on an old theory". general dentistry. 52 (4): 357–61. pmid 15366304. shantipriya reddy, essentials of clinical periodontology and periodontics, 2nd edn (new delhi: jaypee brothers medical publishers, 2008), ch 13 "periodontal medicine", esp pp 115–16. pizzo g, guiglia r, lo russo l, campisi g (2010). "dentistry and internal medicine: from the focal infection theory to the periodontal medicine concept". european journal of internal medicine. 21 (6): 496–502. doi:10.1016/j.ejim.2010.07.011. pmid 21111933. leon chaitow, cranial manipulation: theory and practice, 2nd edn (edinburgh, london, new york, etc.: elsevier, 2005), pp 348–49 & 350–51. in 1876, employing innovative bacteriology protocols more stringently reductionist than previous bacteriology techniques, koch confirmed that a recurrently suspected bacterial species—later named bacillus anthracis—causes anthrax, which thus became the first mammalian disease scientifically explained as infectious. gibbons rv (1998). "germs, dr. billings, and the theory of focal infection". clinical infectious diseases. 27 (3): 627–33. doi:10.1086/514705. pmid 9770165. barry d. silverman, "william henry welch (1850–1934): the road to johns hopkins", proc (bayl univ med cent), 2011 jul;24(3):236–242. r v gibbons, "germs, dr. billings, and the theory of focal infection", clin infect dis, 1998 sep;27(3):627–633. barnett ml (2006). "the oral-systemic disease connection: an update for the practicing dentist". journal of the american dental association. 137 suppl: 5s–6s. doi:10.14219/jada.archive.2006.0401. pmid 17012729. miller wd (1891). "the human mouth as a focus of infection". the lancet. 138 (3546): 340–342. doi:10.1016/s0140-6736(02)01387-9. willoughby d miller, the micro-organisms of the human mouth: the local and general diseases which are caused by them (leipzig: verlag von georg thieme, 1892). shanon patel & justin j barnes, "introduction: how has endodontics developed?", in shanon patel & justin j barnes, eds, the principles of endodontics, 2nd edn (oxford: oxford university press, 2013), pp 4–5. miller wd (1894). "an introduction to the study of the bacteriopathology of the dental pulp". dental cosmos. 36: 505–28. andrew scull, madhouse: a tragic tale of megalomania and modern medicine (new haven: yale university press, 2005), pp 33–37. caroline barranco, "the first live attenuated vaccines", nature portfolio, springer nature limited, 28 sep 2020. alfred i tauber & leon chernyak, metchnikoff and the origins of immunology: from metaphor to theory (new york: oxford university press, 1991), pp viii, 11. immunology's early feuding over whether immunity is innate or is acquired reflected limited perspectives. as later elucidated, antibody molecules, which are secreted by activated b cells, mediate but one arm of acquired immunity, whose other arm is mediated by killer t cells. acquired immunity's two principal mediators, b cells and t cells, are subsets of lymphocytes—themselves a subset of white blood cells, also known as leukocytes—as their base of residence is peripheral lymphoid tissues. on the other hand, innate immunity is mediated not only by phagocytes but also by a third subset of lymphocytes: natural killer cells. further, innate immunity also includes soluble components—complement proteins and, more recently identified, innate antibody secreted by b cells—while yet other lymphocytes, specifically helper t cells, bridge innate immunity and adaptive immunity. chen ts, chen ps (1989). "intestinal autointoxication: a medical leitmotif". journal of clinical gastroenterology. 11 (4): 434–41. doi:10.1097/00004836-198908000-00017. pmid 2668399. philip a. mackowiak, "recycling metchnikoff: probiotics, the intestinal microbiome and the quest for long life", front public health, 2013 nov 13;1:52. andrew h beck, "the flexner report and the standardization of american medical education", jama, 2004 may 5;291(17):2139–2140. lester s king, "medicine in the usa: historical vignettes. xx. the flexner report of 1910", jama, 1984 feb 24;251(8):1079–1086. a i tauber, "the two faces of medical education: flexner and osler revisited", j r soc med, 1992 oct;85(10):598–602, especially pp 599–600. hunter, w (28 july 1900). "oral sepsis as a cause of disease". british medical journal. 2 (2065): 215–6. doi:10.1136/bmj.2.2065.215. pmc 2462945. pmid 20759127. william hunter, oral sepsis as a cause of septic gastritis, toxic neuritis, and other septic conditions (london: cassell & co, 1901). john i ingle, pdq endodontics, 2nd edn (shelton ct: people's medical publishing house, 2009), p xiv. hobart a reimann & paul havens (1940). "focal infection and systemic disease: a critical appraisal". journal of the american medical association. 114. doi:10.1001/jama.1940.02810010003001. frank billings (1912). "chronic focal infections and their etiologic relations to arthritis and nephritis". archives of internal medicine. ix (4): 484–498. doi:10.1001/archinte.1912.00060160087007. frank billings, focal infection: the lane lectures (new york & london: d appleton & co, 1918). edward c rosenow; hazel gray (1918). "agglutination of the pleomorphic streptococcus isolated from epidemic poliomyelitis by immune serum". journal of infectious diseases. 22 (4): 345–378. doi:10.1093/infdis/22.4.345. jstor 30080461. edward c rosenow, ch 43 "elective localization of bacteria in the animal body", in edwin o jordan & i s falk, eds the newer knowledge of bacteriology and immunology (chicago il: university of chicago press, 1928), pp 576–89. "mayo clinic history", mayo clinic, website access: 21 sep 2013. billings f (1914). "mouth infection as a source of systemic disease". journal of the american medical association. 63 (23): 2024. doi:10.1001/jama.1914.02570230034010. mayo ch (1914). "mouth infection as a source of systemic disease". journal of the american medical association. 63 (23): 2025. doi:10.1001/jama.1914.02570230035011. rosenow ec (1914). "mouth infection as a source of systemic disease". journal of the american medical association. 63 (23): 2026. doi:10.1001/jama.1914.02570230036012. s2cid 72457427. "the lewellys franklin barker collection", alan mason chesney medical archives, johns hopkins medical institutions, website access: 23 sep 2013. "the william s thayer collection archived 2013-09-22 at the wayback machine", repository guide to the personal papers collections of alan mason chesney medical archives, johns hopkins medical institutions, website access: 21 sep 2013. copeman wsc (sep 1965). "russell l cecil". annals of the rheumatic diseases. 24 (5): 502. doi:10.1136/ard.24.5.502. pmc 1031019. craig cb (1914). "peridental infection as a causative factor in nervous diseases". journal of the american medical association. 63 (23): 2027. doi:10.1001/jama.1914.02570230037013. weston a price, dental infections, oral and systemic, vol 1 & vol 2 (cleveland: penton publishing, 1923). price wa (1925). "dental infections and related degenerative diseases". journal of the american medical association. 84 (4): 254. doi:10.1001/jama.1925.02660300012006. weston a price, dental infections, oral and systemic, vol 1 (cleveland: penton publishing, 1923), p 488. baumgartner et al, ingle's endodontics, 6th edn (hamilton: bc decker, 2006), p 286, not giving that precise summary, cite buckley–price debate on the subject: price weston a, buckley john p (1925). "resolved: that practically all infected pulpless teeth should be extracted". journal of the american dental association. 12: 1468–524. doi:10.14219/jada.archive.1925.0307. british journal of dental science, 1928;72:101. examples: william h o mcgehee, a text-book of operative dentistry, 2nd edn (philadelphia: blackiston's son & co, 1936), pp 39 & 110; louis v hayes, clinical diagnosis of diseases of the mouth: a guide for students and practitioners of dentistry and medicine (brooklyn ny: dental items of interest publishing, 1935), p 389. kracher cm (2000). "c. edmund kells (1856-1928)". journal of the history of dentistry. 48 (2): 65–9. pmid 11794365. ada: "c edmund kells was a dental pioneer who championed the use of x-rays in dentistry during the late 19th century and early 20th century. 'the x-ray in dental practice' is a paper read by dr kells at a 1919 association meeting in new orleans. much of the paper discusses focal infection theory, which dr kells argued was leading to the unnecessary extraction of teeth. he also made it clear that dental x-rays should be used to enhance dentistry, and not to encourage the 'mania for extracting devitalized teeth' " . journal of the canadian dental association, 1935;1:451. c murray, ch 48 "endontology and general systemic health", §§ "the 'focal infection' era" & "effects of general systemic health on endodontics", in michael baumann & rudolf beer, eds, endodontology, 2nd edn (new york: thieme, 2010). noll richard (apr 2004). "historical review: autointoxication and focal infection theories of dementia praecox". world journal of biological psychiatry. 5 (2): 66–72. doi:10.1080/15622970410029914. pmid 15179665. s2cid 41416327. wessely s (october 2009). "surgery for the treatment of psychiatric illness: the need to test untested theories". journal of the royal society of medicine. 102 (10): 445–51. doi:10.1258/jrsm.2009.09k038. pmc 2755332. pmid 19797603. henry a cotton, the defective, delinquent, and insane: the relation of focal infections to their causation, treatment and prevention (princeton/london: princeton university press/oxford university press, 1922). phil fennell, treatment without consent: law, psychiatry and the treatment of mentally disordered people since 1845 (london & new york: routledge, 1996), p. 120. robert t morris: "the matter of focal infections is one of the very new subjects of the day which men are taking up with a great deal of interest but are going ahead perhaps with incomplete knowledge and not comprehending the range and scope of the entire subject; consequently this subject is falling into disrepute in certain fields because of the over-enthusiasm of some of the advocates of focal infection theory in relation to distant demonstration—endocarditis, rheumatism, gastric ulcer, cholecystitis, various forms of neuritis, etc. the philosopher, taking all evidence judicially, will eventually give the medical profession the basic facts and what is valuable in the subject. right now one might utter a warning to the general medical profession against taking too active an interest in the subject." . c edmund kells, "x-ray in dental practice", journal of the national dental association, 1920 mar;7(3):241–72 . jacobsohn ph, kantor ml, pihlstrom bl (2013). "the x-ray in dentistry, and the legacy of c. edmund kells: a commentary on kells ce. the x-ray in dental practice. j natl dent assoc 1920;7(3):241-272". journal of the american dental association. 144 (2): 138–42. doi:10.14219/jada.archive.2013.0092. pmid 23372129. richard noll, the encyclopedia of schizophrenia and other psychotic disorders (new york: facts on file, 2007), pp 170–170. shorter e (2011). "a brief history of placebos and clinical trials in psychiatry". canadian journal of psychiatry. 56 (4): 193–7. doi:10.1177/070674371105600402. pmc 3714297. pmid 21507275. kopeloff nicolas, cheney clarence o (oct 1922). "studies in focal infection: its presence and elimination in the functional psychoses". american journal of psychiatry. 79 (2): 139–56. doi:10.1176/ajp.79.2.139.kopeloff nicolas, kirby george h (oct 1923). "focal infection and mental disease". american journal of psychiatry. 80 (2): 149–91. doi:10.1176/ajp.80.2.149. henry w crowe & herbert g franking, "aetiology continued: dental infections and degenerative diseases—a review and commentary", pp 23–32, bacteriology and surgery of chronic arthritis and rheumatism with end-results of treatment (new york/london: humphrey milford/oxford university press, 1927), p 32. russell l cecil & d murray angevine, "clinical and experimental observations on focal infection, with an analysis of 200 cases of rheumatoid arthritis", annals of internal medicine, 1938 nov 1;12(5):577–584. fish e wilfred