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Medical Dictionary


noun aphe·re·sis\ˌa-fə-ˈrē-səs\
plural aphe·re·ses \-ˌsēz\

Medical Definition of APHERESIS

:  withdrawal of blood from a donor's body, removal of one or more components (as plasma, blood platelets, or white blood cells) from the blood, and transfusion of the remaining blood back into the donor—called also pheresis; see leukapheresis, plasmapheresis, plateletpheresis


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