{HEAD ~ Initiation} may be achieved by adding a blood coagulation factor {TAIL ~ XII activator} to animal plasma in the presence of the test substance 
{ HEAD ~ Initiation } may be achieved by adding a blood coagulation factor { TAIL ~ XII activator } to animal plasma in the presence of the test substance
HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH