rktr()(;rkssive tissuI': ciiangks. 221 



Microscopic. — When examined in the fresh state the cells 

 are enlarged, the extent of which depends upon the (|uantity of 

 fluid imbibed. The infiltrated fluid accumulated in the cells 

 appears as clear spaces or vacuoles. The vacuoles occur either 

 in the cyto-plasm or the nucleus and in extreme cases, they 

 occupy the entire cell and may even cause its rupture. 



Tissues Affected. — Practically all tissues are subject to 

 serous infiltration. Those tissues in which oedema occurs are 

 most frequently aft'ected. Epithelium is quite fre(|uentlv in- 

 volved in serous infiltration because this tissue forms the sur- 

 face of those structures affected with oedema. 



Effects. — The eft'ects depend upon the extent and duration 

 of the condition. Some vegetable cells are capable of imbibing 

 fluid to a sufficient extent that thev increase their size one hun- 

 dred times. 



Animal cells cannot imbibe fluids to such an extent as vege- 

 table cells without being rent asunder. After the cells have 

 been subjected to serous infiltration f(_)r sometime, the nuclear 

 chromatin appears to dissolve and diffuse through the cell bodv. 

 This necessitates an impairment of the cell activities. 



Gf.YCOGENfC INFfETRATION. 



DEFIXITION. 



ETIOLOGY — ( Disturbed carbohydrate metabolism). 



APPEAR.-INCE. 



Macroscof'ic. 



.Microseol^ie. 

 T!.'?SUE AFFECTED. 

 EFFECTS. 



This is a condition characterized by the infiltration of exces- 

 sive quantities of glvcogen into cells that normally contain a 

 limited amount of it or the infiltration of glycogen into cells 

 normally glycogen free. 



The source of glycogen is not definitely known. Accord- 

 ing to some physiologists, glycogen may be formed from either 

 carbohydrates or proteids. The digested carbohydrates are 

 probably stored up in the form of glycogen, at least glycogen 

 is readily converted into dextrose whenever carbohydrates are 

 needed. Glycogen can be demonstrated in the normal liver cells, 

 kidney cells, and in muscle cells, although it occurs in limited 

 quantities. 



Glvcogen is soluble in water and insoluble in alcohol, chloro- 

 form and ether. Its presence in tissue may be demonstrated by 

 smearino- the tissue on a slide and allowing it to dry inverted. 



