Department of Anesthesiology;
the First Affiliated Hospital;
School of Medicine;
Zhejiang University;
Hangzhou 3 10003;
china;
Department of Orthopedics the First Affiliated Hospital;
School of Medicine Zhejiang university;
Hangzhou 310003;
china;
血液稀释; 体积膨胀; Ringer溶液; 全身麻醉; 硬膜外麻醉;