{TAIL ~ The amount} of reducing substance and {HEAD ~ the period} of time for interaction are so adapted to obtain the product desired, whereafter the blood and plasma, respectively, are optionally fractionated in a known manner 
{ TAIL ~ The amount } of reducing substance and { HEAD ~ the period } of time for interaction are so adapted to obtain the product desired , whereafter the blood and plasma , respectively , are optionally fractionated in a known manner
TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD 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 OTH