INFECTIONS OF THE DIGESTIVE TRACT 313 



moderate that little harm could be accomplished by them 

 in a person with normal defenses. But in a person with 

 greatly impaired defenses and diminished hsemopoi- 

 etic powers (correlative to parenchymatous changes 

 in the hepatic and other cells, on alteration in the bone 

 marrow) the absorbed poisons suffice ultimately to make 

 blood destruction preponderate permanently over blood 

 formation. A relatively slight putrefactive process in 

 the intestine thus ushers in the signs of the severe 

 anaemia. 



