Chubu choyezera chofiirira ndiye ngwazi ya mayeso a hematology, chifukwa ethylenediaminetetraacetic acid (EDTA) momwemo imatha kutsitsa ayoni a calcium mumwazi wamagazi, kuchotsa calcium pamalo omwe adachitika, kutsekereza ndikuyimitsa njira yamkati kapena yakunja. kuti tipewe kugundana kwa chitsanzocho, koma zimatha kupangitsa kuti ma lymphocyte awoneke ngati nyukiliya yooneka ngati maluwa, komanso kulimbikitsa kuphatikizika kwa mapulateleti omwe amadalira EDTA.Chifukwa chake, sangagwiritsidwe ntchito poyesa kuyesa kwa coagulation ndi kuyesa ntchito ya mapulateleti.Nthawi zambiri, timatembenuza ndi kusakaniza magazi atangotenga magazi, ndipo chitsanzocho chiyeneranso kusakanikirana chisanayambe kuyezetsa, ndipo sichikhoza kukhala centrifuged.