DISEASES OF THE DIGESTIVE ORGANS 39 



juice by the bile, pancreatic juice and intestinal secretions, all of 

 which are alkaline. Intestinal digestion takes place principally 

 in the small intestines. In the large intestines a further digestion 

 takes place, and here also occur, especially in the caecum, in addi- 

 tion to the resorption of the fluid and dissolved substances, fermen- 

 tative and putrefactive processes (indol, skatol, phenol, cresol, 

 fatty acids, amido acids, ammonia, carbon dioxide, hydrogen, 

 hydrogen sulphide, and other products of the decomposition of 

 albumin and cellulose). In contrast with the small intestines, the 

 large intestines, on account of the alkaline reaction and the ab- 

 sence of oxygen, are a place for the incubation of anaerobic bacteria 

 (colon bacillus, bacillus putrificus — decomposers of albumin). 

 The bile and the pancreatic juice are the most important of the 

 digestive secretions, the intestinal juice possessing only a slight 

 amylol3rtic and at times a proteolytic action. The bile possesses 

 antitoxic and antiseptic properties (immunization in infectious 

 diseases, removal of poisons from the blood). It also prepares 

 the fats for absorption in the intestines and operates as a stim- 

 ulant to peristalsis of the large intestines. The pancreatic 

 juice contains proteolytic (trypsin), amylolytic and fat-splitting 

 ferments. 



In regard to intestinal absorption it is to be noted that the 

 nutrient substances in solution and the fats are absorbed by the 

 activity of the intestinal epithelium and the contraction of the 

 villi, assisted by the amoeboid functions of the leucocytes (phago- 

 cytosis). The water-soluble substances are also taken up by dif- 

 fusion. When the intestinal epithelium is desquamated over a 

 considerable area, as in catarrh, or when the intestinal villi are 

 paralyzed, as in inflammation, then absorption is distributed or 

 entirely suppressed. 



Therapeutic Methods. — The diseased intestine may be influ- 

 enced in several ways. The mucous membrane may be treated 

 directly with demulcents, narcotics, astringents, antiseptics or 

 stimulants. The glands may be acted upon by pilocarpine or 

 arecoline; the muscles by eserine or barium chloride; the nerves by 

 morphine. Treatment of the intestinal contents is also very impor- 



