Factor Xa, with Factor Va as a cofactor, turns factor II (also called prothrombin) into factor IIa or thrombin.

活性因Xa和作辅因的因Va将因II（原）转变因IIa（）。

So, it starts with a protein called thrombomodulin, which is on endothelial cells that line our blood vessels, and together with thrombin, they form a complex that also includes protein C and protein S.

这一过程从栓调节蛋白开始，它位于管的内皮细胞中，与形成一个复合物，其同时也包含蛋白C和S。