1. Department of Thoracic Surgery, First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, P.R. China
2. Department of Colorectal Surgery, First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, P.R. China
3. Department of Pancreato-Biliary Surgery, First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, P.R. China
4. Operation Centre, First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, P.R. China
5. Division of Cardiac Surgery, First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, P.R. China