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Prothrombin in Enzymology, Thrombosis and Hemophilia

Oscar D. Ratnoff, MD
JAMA. 1967;202(9):918. doi:10.1001/jama.1967.03130220106039.
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Blood Clotting Enzymology, edited by Walter H. Seegers, 628 pp, with illus, $27.50, New York and London: Academic Press, Inc., 1967.

Probably most of those interested in the physiology and pathology of blood clotting believe that coagulation is the end result of a series of enzymatic reactions involving numerous individual clotting factors. The "cascade" or "waterfall" hypothesis of blood coagulation, which envisions a series of catalytic reactions among these factors, is a tentative expression of this belief that has been fruitful in suggesting new experiments and new ideas. No proponent would claim more than that, for history shows that today's hypothesis is destined for tomorrow's waste basket. One of my acerbic colleagues points out that the solution of all clotting problems would leave him unemployed.

Perhaps the greatest impetus to science is not curiosity but rather controversy among men who see the same facts through different lenses. Seegers, one of


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