GLOBULOCIDAL AND OTHER PROPERTIES OF SERUM 145 



be seldom exactly the same. Speaking generally and without considering 

 the sugar and other soluble matters which may have been absorbed from 

 the alimentary canal, this blood appears to be deficient in solid matters, 

 especially in colored corpuscles, owing to dilution by the quantity of water 

 absorbed, to contain an excess of protein matter, and to yield a less tenacious 

 kind of fibrin than that of blood generally. 



The blood of the portal vein, combining the peculiarities of its two factors 

 the splenic and mesenteric venous blood, is usually of lower specific gravity 

 than blood generally, is more watery, contains fewer colored corpuscles, 

 more proteins, and yields a less firm clot than that yielded by other blood, 

 owing to the deficient tenacity of its fibrin. 



Guarding (by ligature of the portal vein) against the possibility of an 

 error in the analysis from regurgitation of hepatic blood into the portal vein, 

 recent observers have determined that hepatic venous blood contains less 

 water, proteins, and salts than the blood of the portal veins; but that it yields 

 a much larger amount of extractive matter, in which is one constant element, 

 namely, grape-sugar, which is found whether saccharine or farinaceous 

 matter has been present in the food or not. 



GLOBULOCIDAL AND OTHER PROPERTIES OF SERUM. 



Cytolysis. It has been known for some time that the sera of certain 

 animals when injected into the circulation of animals of another species will 

 cause destructive changes in the blood corpuscles, accompanied by symptoms 

 of poisoning, which may even end fatally. These results served to bring into 

 disrepute the use of foreign blood in transfusion, which has consequently 

 been practically abandoned. This discharge of the hemoglobin of the red 

 blood corpuscles and solution in the plasma (laking) is now included in the 

 general term Cytolysis, and more specifically known as Hemolysis. Agents 

 which produce such an effect are known as hemolytic or hemotoxic agents. 

 Sera of one species are not hemolytic for blood of all other species, but the 

 serum of one animal made be made to acquire such properties for the blood 

 of another. 



This adaption is brought about in the following way: For instance, 

 the blood of the guinea-pig, which is not normally lytic for the red cells of the 

 rabbit, may be adapted to the latter by previously, at several successive 

 intervals (three to seven days) injecting into the abdominal cavity or sub- 

 cutaneous tissues of the guinea-pig small quantities of rabbit's blood. If 

 now a small quantity of serum be obtained from the guinea-pig by the usual 

 methods and mixed in a test-tube with some of the rabbit's blood diluted 

 with physiological salt solution, hemolysis occurs; that is, the coloring 

 matter of the rabbit's red blood-cells goes into solution and the cells appear 

 under the microscope as shadow corpuscles or ghosts, devoid of hemoglobin. 



