platelet activation was measured by radioimmunoassay of plasma platelet factor 4 ( pf4 ) , beta-thromboglobulin ( btg ) , and thromboxane b2 ( txb2 ) in blood samples withdrawn through catheters , and fibrin formation was assessed by determination of fibrinopeptide a ( fpa ) levels .
C0015982
fibrin
C0016022
fibrinopeptide a