{HEAD ~ That reference} discloses that ornithine decarboxylase activity increased {TAIL ~ precedent} to polyamine biosynthesis 
{ HEAD ~ That reference } discloses that ornithine decarboxylase activity increased { TAIL ~ precedent } to polyamine biosynthesis
HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH