DISEASES OF THE BEOOD. 



Obscurity of blood changes. Red globules, biconcave, embr\onic. 

 Source. Escape of immature red globules. White globules, eosinophile, 

 ueutrophile, uninuclear, multinuclear, lymphocyte, granular amoeboid, strap- 

 nucleated. Conditions of increase. Relation to microbes and their pro- 

 ducts. Blood plates. Destruction of red globules in the liver. Numbers 

 in animals, in different vessels and conditions. 



The blood is the common medium through which all nouri.sh- 

 ment is conveyed to the tissues, all material to the glands for se- 

 cretion, or transformation, and all effete matter to the various 

 emunctories for elimination. It is beside the carrier of oxygen 

 for the respiration of the tissues, and the seat of changes, as yet 

 little known, effected through the white globules. The activities 

 of the various processes, carried on by the fixed tissue cells and 

 nuclei would suggest, that any disease or derangement of the.se 

 processes would be at once cognizable in changes shown in the 

 blood. Yet so perfect is the balance of sanguification and elimi- 

 nation on the one hand, and of the remaining vital processes oh the 

 other, that it has hitherto been impossible to detect in the blood 

 such changes as would identify the great majority with morbid 

 processes. Some morbid changes are however recognizable and 

 it is important that the significance of these should be known. 



The blood is a liquid, con.si.sting of a plasma holding in solution 

 .serum albumen, serum globulin, fibrine-forming elements, sugar, 

 urea, .salts, and a variety of other .soluble bodies, and floating a 

 series of semi-solid organized bodies, the red and white globules. 



The red globule is however seen in two distinct forms, ist. 

 The biconcave disc, non-nucleated, containing a colorless .stroma, 

 and the coloring matter — haemoglobin. 2d. The embryonic red 

 globule, large, nucleated and rarely biconcave. The latter is found 

 in the blood of the fcEtal man or animal and persists to a slight 

 extent for .some time after birth. These are believed to be formed 

 from the embryonic cell and from the cells of the embryonic liver, 

 spleen, and marrow, whereas afterbirth they are derived from the 

 marrow cell, and in healthy conditions pass the nucleated stage 

 before they escape into the blood. In pathological anaemia and 



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