Optical profiles measured during APTT coagulation assays in normal and BPW-positive plasma.

Profiles from normal plasma (○) and plasma with a biphasic waveform (▵) and the same sample with the thrombin inhibitor hirudin (■) in the APTT assay with the Organon Teknika MDA coagulation analyzer. Solid traces are the optical waveforms. Symbols are included only to differentiate the samples.