IXKLAMMATIOX. 161 



oedema, e. g., the tumefaction accompanyino- tendonitis is dense, 

 while the swelling accompanying "stocking" is soft and doughy. 



The tcmhcrat'irc ( Calor ) of tissue affected with active' in- 

 flammation is invariably increased. This is the result of the 

 excessive cellular action in the inflamed area and the increased 

 amount of blood flowing intd the part. 



Paiii (Dolor) is a common symptom of inflammation. This 

 may be the result of pressure upon nerve endings bv the accu- 

 mulated exudate. However, oedema is accompanied bv an ex- 

 cessive accumulation of fluid in the tissues, and ncdematous 

 tissues are not hypersensitive. It seems more probable that in- 

 flammatory pain is the result of the injurious action of the 

 irritant or soluble products of the exudate upon the sensory 

 ner^•e endings. The inflammatory pain is often referred tn some 

 other part of the body, e. g., in pleurisy the pain frequently 

 appears abdominal. 



Iinpaircd function ( Functio laeso ) is a constant feature ob- 

 served in inflammation. In the beginning of the process the 

 function of the affected tissues (especially secretor^-) is in ex- 

 cess of the normal, 1nit this is succeeded in the later stages by 

 depression of the function. The increased function is a result 

 of increased nourishment, increased stimulation, and probably 

 increased pressure is also a factor; the depressed or diminished 

 function is the result of the injurious action of kataliolic prod- 

 ucts, produced bv excessive cellular action, and of the irritant 

 producing the inflammatory process. Thus, in the beginning 

 of acute nephritis there is an excessive amount of fluid (urine) 

 excreted, this is succeeded by rliminution or complete suppres- 

 sion of the excietion (urine). 



Effects upon the Tissue Involved. — As a result of 

 the inflammatory process the tissues invuh-ed may un- 

 dergo various changes. These changes may be (Ic</nicrati7'c, 

 necrotic, rec/eneratnr or prolifcratii'c in character. I3egenera- 

 tion usualh' precedes regeneration, but the two conditions may 

 be independent of each other; thus in ulceration, degeneration 

 and necrosis may alone be evident, and in the formation of a 

 tubercle of tuberculosis proliferation is the principal process. 

 Both conditions may exist at the same time in different parts 

 of an affected area, degeneration taking place in the center of 

 the diseased area and regeneration or proliferation in the peri- 

 phery. Inflammation not accompanied by cither degeneration 

 or regeneration is rare. The injuries or irritants establishing 

 inflammation may and frequently do produce death of some of 

 the tissue cells; necrotic tissue is sufficiently irritating to pro- 



