Usefulness of new analytical reagents demonstrated with coumadin-modified plasma.

Prothrombin, factor X or factor IX were removed specifically from bovine plasma by immunological techniques. Each depleted plasma is responsive to the respective purified component, and was used to follow the blood changes produced in a steer's blood by Coumadin administration. A factor IX-VII reagent was also used to follow changes in factor IX and factor VII activity. It is suggested that the new reagents may have practical value for qualitative and quantitative work in blood coagulation studies.