1. Department of Gastrointestinal Colorectal & Anal Surgery, China-Japan Union Hospital of Jilin University, Changchun, China
2. Department of Anesthesiology, Jilin Cancer Hospital, Changchun, China
3. Department of Education, The Second Hospital of Jilin University, Changchun, China
4. Department of General Surgery, The Second Hospital of Jilin University, Changchun, China