162 



VETERI-XARV PATH(iLU(;y. 



duce inflammation, and necrotic areas are usually surrounded 

 by an inflammatorv zone. Inflammation is confined to the 

 reactiA-e process of the injured cells and should not be confused 

 with the death of the cells or necrosis. 



Degeneration and regeneration are distinctly opposite pro- 

 cesses. The former is destructive, resulting in impairment and 

 death, Avhile the latter is constructive, resulting in overgrowth 

 and proliferation. Degeneration is caused by insufficient food, 

 inhibition of irritating pruducts, or excessive and frerpiently 

 perverted functional activity. Regeneration occurs when there 

 is an adequate supply of nutrition, and depends upon the rcver- 



a. Alvi-iilus 

 b. Fihrfnis lii"< 



-Clironie Pneumonia. 



c, AA'antlf rinj^ ]euct:.c>tes. 



sion of the cells to the embryonic type or stimulation of the 

 reproductive properties of the cells, the latter usually at the 

 expense of the normal functional activity. Both processes affect 

 the cellular elements of the tissues, primarily and actively, and 

 the intercellular substances secondarily and passively. Some 

 e.xceptions will be mentioned later. The leucocj'tes and wander- 

 ing cells mav also undergo changes similar to those which the 

 fixed tissue cells are subject. In general, degeneration character- 

 izes acute inflammation and regeneration characterizes chronic 

 inflammation. The importance of either of the above processes 

 depends upon their extent The general consideration of the two 

 processes has been combined for the sake of comparison ; but 

 thev will now be considered separately. 



Dcc/cncratioii. — Practically all degenerations, to which tis- 



