Time course of thrombin generation in simulated patients' plasma and in normal plasma. (A-B) FV-FVII doubly deficient plasma, to which 0.2% normal plasma had been added, was reconstituted with purified normal FV (○), 50% normal FV and 50% FV Leiden (), and FV Leiden (•). Reconstituted plasmas and normal plasma were triggered with approximately 6.4 ng/mL TF in the absence (A) and in the presence (B) of 20 nM APC, and thrombin generation was followed continuously with a fluorogenic substrate. (C) Normal plasma triggered in the absence (⋄) and in the presence (♦) of APC.