Methods The cell-free system was prepared by ultracentrifugation of Xenopus eggs and activated by cytochrome C.

方法超速心制备非洲爪蟾卵无细胞体系,细胞色素C激活为凋亡体系。

We separated the subfractions of LDL by precipitating method and density gradient ultracentrifugation, and identified the subfraction by electronphoresis and electron microscope.

通过沉淀法LDL,后经过超速心法其亚组。