Preferably {TAIL ~ the fluids} contain blood or {HEAD ~ blood products} and comprise biologically active proteins 
Preferably { TAIL ~ the fluids } contain blood or { HEAD ~ blood products } and comprise biologically active proteins
OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH