Sentence:  The red cells for the Rh antibody tests were <WSD>used</WSD> within 3 days after drawing except for the * * f cells , which had been glycerolized and stored at - 20 ` C for approximately 1 year . 
Meaning of the word marked with <WSD> tags:  put into service; make work or employ for a particular purpose or for its inherent or natural purpose