ALIMENTARY TRACT AS AN ABSORPTIVE SYSTEM. 303 



were able to show that the nitrogenous excretion of dogs 

 could be covered entirely through the nitrogen obtained 

 from finely minced meat, eggs, etc., introduced directly into 

 the duodenum through a fistula, and more recently a number 

 of operations carried out on human beings in which all or 

 nearly all the stomach has been removed have shown that 

 absence of this organ does not jeopardize life. The pan- 

 creas with the small intestine is able to take care of all the 

 protein necessary for the life of the individual. For reasons 

 which have already been pointed out, such patients do best 

 on sterile food, for the gastric juice is no longer present to 

 reduce the number of bacteria consumed with the ordinary 

 food; and since an organ is no longer present which acts as a 

 reservoir for the food and gives small amounts periodically 

 to the intestine, repeated feedings only can be well tolerated. 

 Since the acid of the gastric juice is best able of all the ali- 

 mentary secretions to act upon the connective tissues, these 

 appear in the faeces after the stomach is gone. ^/ 



The experiments which have been made to determine the 

 importance of the stomach as an absorptive organ for the 

 proteins are not free from criticism. They seem to indicate, 

 however, that a small percent, perhaps, of the total amount 

 of the protein in an ordinary meal may be absorbed by the 

 gastric mucous membrane. As the chief absorptive organ 

 cf the proteins we must regard the small intestine, more 

 especially the upper half. This absorptive power decreases 

 apparently from above downwards, reaching a very low 

 grade in the large intestine. 



According to most observers the pancreas plays a much 

 heavier role than the stomach in the digestion of the 

 proteins. Total extirpation of the pancreas is fatal, for this 

 is followed by a diabetes which ends the life of its vic- 

 tim in a few days. For this reason it becomes necessary in 

 experiments on the digestive functions of the pancreas to 

 limit oneself to occlusion of the pancreatic duct or ducts by 

 means of ligatures, or to only partial excision of the pancreas, 



