the autocatalytic activation of factor x by factor xa described previously occurs to a marked extent only at very low activator concentrations , and has been shown to proceed largely by the loss of the normal nh2-terminal peptide from the heavy chain of i1-initial experiments show that neither peptide affects the rate of coagulation by either the extrinsic or intrinsic pathways .
C0015518
factor x
C0015520
factor xa