THROMBOSIS 315 



reduce the phagocytic power for coal particles by 2.5-50 per cent. 

 Hamburger's results as to the bactericidal power of human blood in 

 venous stasis have been confirmed by Laqueur.'"* Schiller ascribes this 

 not to increased alkalinity, but to disintegration of leucocytes with 

 liberation of bactericidal substances. ^^ 



The blood in the veins and capillaries in passive congestion is gen- 

 erally richer in corpuscles than normal, perhaps because of some loss 

 of water,^*^ although this is not constant, applying particularly to 

 more recent or more local processes; in long-continued stasis, as in 

 congenital heart disease, the blood may be diluted." In the concen- 

 trated blood of passive congestion the corpuscles may number six to 

 eight minions per cubic millimeter, while the concentration of the 

 solids of the serum may be at the same time reduced (Krehl). The 

 viscosity of such blood is higher than that of normal blood. ^^ In 

 acute stasis the proportion of serum proteins, especially the albumin, 

 increases with the duration of the stasis; no changes occur in the non- 

 protein constituents of the blood (Rowe).^^ 



THROMBOSIS 



The chemistry of thrombosis in most respects resolves itself into the 

 chemistry of fibrin formation, a subject which is so extensively con- 

 sidered in most treatises on physiological chemistry and physiology 

 that it does not seem desirable to give here anything more than the 

 essential principles involved in the clotting of the blood, as now under- 

 stood, as an introduction to the consideration of the same process as 

 it occurs under pathological conditions. In spite of innumerable in- 

 vestigations, our knowledge of the actual participants and processes 

 involved in the formation of fibrin is in a very unsatisfactory and 

 fragmentary state. Some facts seem well established, however, and 

 we have a general idea of the subject that may be applied with ad- 

 vantage to the consideration of thrombosis. 



Fibrin Formation^o 



Several different substances seem to be concerned in the formation of fibrin, 

 of which the first of importance is its antecedent, fibrinogen. Fibrinogen is a 

 simple protein, related to the globulins, and differing chiefly in its ready coagula- 

 bility, not only by fibrin ferment, but also by heat, salts, and other coagulating 

 agencies. By itself, however, it shows no tendency to coagulate spontaneously. 

 According to Goodpasture," fibrinogen is formed through the combined activity 



" Zeit. exp. Path. u. Therap., 1905 (1), 670. 



" Beitr. klin. Chir., 1913 (84), H. 1. 



56 Grawitz, Deut. Arch. f. klin. Med., 1895 (54), 588. 



^' See Krehl, " Pathologische Physiologic," 1904, p. 201. 



58 Determann, Zeit. klin. Med., 1906 (59), H. 2-4. 



" Jour. Lab. Clin. Med., 1916 (1), 485. 



^° For literature and full discussion see Hamniarsten's or Mathew's Physiolog- 

 ical Chemistry; Morawitz, Ergebnisse der Physiol., Abt. 1, 1904 (4), 307, and 

 Handbuch d. Biochem., 1908 II (2), 40; Leo Loeb, Biochem. Centr., 1907 (6), 

 829; Howell, Harvey Lectures, 1917. 



" Amer. Jour. Phvsiol., 1914 (33), 70. 



