26 GASTRIC DIGESTION OF PROTEINS 



tected by any tegumentary covering, after as much as a 

 month's exposure. The Italian author just mentioned has 

 concluded therefore that the living cell protects itself against 

 the digestive enzymes of the stomach, intestine, and pan- 

 creas, not by antienzymes, nor by protective coverings, nor 

 yet by any special sort of impermeability, but much more 

 likely by the resistive ability of the whole living cell itself. 

 The simple reply to the question why the living cell is not 

 attacked is therefore this: "Because it is alive. " With 

 such an answer the problem has circled back to exactly the 

 same point where Hunter started one hundred and forty 

 years ago. It is to be hoped that perhaps the next century 

 and a half will really accomplish something in the way of 

 progress. 



Origin of the Round Ulcer of the Stomach. In a 

 limited way the question as to the mode of origin of the 

 round ulcer of the stomach is related with that of gas- 

 tric autodigestion. Time after time explanations for this 

 lesion have proposed some local circulatory disturbance 

 in a given area of the mucosa (from a spasm of the vessels, 

 thrombosis or hemorrhage) with autolysis of the portion 

 involved. 75 We have been able repeatedly, too, to produce 

 gastric ulcers experimentally in animals, as by injection of 

 diphtheria toxin, 76 gastrotoxic serum, 77 by feeding bouillon 

 cultures of bacterium coli, 78 by repeated serum injections 7d 

 (as one of the features of anaphylaxis), as well as by the 

 poison of the Gila monster (Heloderma suspectum) . 80 The 

 last mentioned experiments (conducted under Leo Loeb) 



75 Cf. the extensive material of R. Beneke, Verb. d. Deutsche pathol. Ges., 

 Kiel, 1908, 284. 



70 Eosenau and Anderson, Journ. Infect. Diseases, 4, 1, 1907. 



77 M. J. Bolton, Proc. Roy. Soc., 1905-06, Series B, 77 ; 1909, Series B, 79, 

 cited by Rehfuss, v. infra. 



F. B. Turck, Journ. Amer. Med. Assoc., 1906, 1753, cited by Rosenau and 

 Anderson, v. sup. 



79 Gay and Southard, Journ. of Med. Research, 1908, cited by Rehfuss, 

 y. infra. 



80 M. E. Rehfuss, University of Pennsylvania Medical Bulletin, 22, 105, 1909. 



