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Demonstration of three anomalous plasma proteins induced by a vitamin K antagonist
P P Reekers1, M J Lindhout, B H Kop-Klaassen
1Laboratory for Cardiovascular and Blood Coagulation Biochemistry, Leiden University Medical Centre, Leiden, The Netherlands.
Abstract:
With the aid of precipitating antibodies against the bovine coagulation factors II, IX, and X three immunologically non-identical proteins can be demonstrated that are induced by the administration of a vitamin K antagonist (phenprocoumon). Each of these proteins is immunologically identical to one of three coagulation factors mentioned. The proteins differ from normal coagulation factors (a) by a lack of biological activity; (b) by a faster anodic migration rate in the presence of Ca2+. The proteins appear in the plasma concomitantly with the decrease of the normal factor.
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