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

方法超速离心洲爪蟾卵无细胞,细胞色素C激活为凋亡。

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

过沉淀法分离LDL,然后经过超速离心法分离其亚组分。