PATHOLOGY. 



INTRODUCTORY. 



Pathology (nado^, disease, and ^oc, discourse) is the science 

 which treats of animal and vegetable life under abnormal 

 conditions i. e., the science of disease. It is that branch 

 of medicine which considers abnormalities of structure and 

 function, the causes thereof, and the relation of these changes 

 to the clinical aspects of disease produced thereby. 



Human pathology then includes the study of etiology or the 

 causes of disease ; morbid anatomy macroscopical and micro- 

 scopical ; and morbid or pathological physiology. With these 

 must always go hand in hand clinical observation, in order 

 that a true conception may be formed of disease-processes. As 

 our knowledge of anatomy is more advanced than that of 

 physiology, so our knowledge of morbid anatomy is more 

 perfect than that of morbid physiology. 



The importance of this branch of medicine cannot be over- 

 estimated by the student ; it is the one sure basis for diag- 

 nosis, prognosis, and rational therapeusis. Some of the 

 greatest additions to medical knowledge have been made by 

 the study of morbid anatomy in conjunction with clinical 

 observation. Apoplexy was supposed to be due to the inter- 

 ruption of certain imaginary spirits till Wepfer showed cere- 

 bral hemorrhage to be the cause in a large number of cases. 

 In this manner Bright demonstrated the relation between 

 certain alterations in the kidneys, and albnminuria and dropsy. 

 Typhoid and typhus fevers were regarded as identical until 

 1836, when a post-mortem study of the lesions present proved 

 the contrary. The mediaeval physician rarely endeavored to 

 locate the seat of a disease certainly not beyond assigning 

 it to one of the larger cavities of the body, i. e., the head, 



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