maximal suppression ( 74 % ) occurred when the parasites were present during the entire culture period ( 96 hr ) , although significant suppression ( 33 % ) was seen when the organisms were added 24 , 48 or 72 hr after initiation , suggesting that the early stages of lymphocyte activation had been impaired and that a second generation of cells was also affected .
C0030498
parasites
C0029235
organisms