PARENTEKAL DIGESTION 63 



a predilection for epithelial tissues and mani- 

 fests its destructive action in the skin and in 

 mucous membranes. It has long been known 

 that peptic ulcer is frequently associated with 

 chronic appendicitis and the recent brilliant 

 work of Rosenow has called attention to the 

 probable relation between peptic ulcer and 

 pyorrhea. In case of a nidus of infection in 

 any part of the body poisonous proteins are be- 

 ing poured into the circulation and these like 

 other poisons are carried to the walls of the in- 

 testine for the evident purpose of elimination. 

 Here they accumulate and in their reaction with 

 the body cells, the latter are more or less in- 

 jured. The elimination of proteins from the 

 blood into the alimentary canal holds for both 

 living and dead, formed and unformed proteins. 

 This is an interesting phase in the study of the 

 action of poisonous proteins and is worthy of 

 further study. 



It has been long known that blood serum, like 

 living cells, is highly resistant to proteolytic 

 enzymes. Furthermore, the presence of blood 

 serum markedly retards both peptic and pan- 

 creatic digestion. It has been generally in- 

 ferred from these facts that blood serum con- 

 tains an antiproteolytic ferment and since the 

 reaction is alkaline, this is generally designated 



