{HEAD ~ The present invention} provides {TAIL ~ a method} of measuring the activity of a substance to test how it inhibits or promotes the production of the blood coagulation factor XII in an active form  
provides
{ HEAD ~ The present invention } provides { TAIL ~ a method } of measuring the activity of a substance to test how it inhibits or promotes the production of the blood coagulation factor XII in an active form
HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH