The median survival time(MST) of N-Control, C-Control and Dex was 10, 17 and 16 days respectively, and had no difference each other(P0.05).

• 三、(l)各组大鼠术后存活时间:N一Control组(n=7) MST二10天、C一Control组(n=8)MST=17天和Dex组(n=8)MST=16天，术后存活时间无明显差别;