1. Tumor Etiology & Screening Department of Cancer Institute & General Surgery, the First Hospital of China Medical University, Shenyang 110001, PR China
2. Key Laboratory of Cancer Etiology & Prevention in Liaoning Education Department, the First Hospital of China Medical University, Shenyang 110001, PR China
3. Key Laboratory of GI Cancer Etiology & Prevention in Liaoning Province, the First Hospital of China Medical University, Shenyang 110001, PR China
4. Department of Anesthesiology, the First Hospital of China Medical University, Shenyang 110001, PR China