1. Department of General Surgery, The Second Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215004, P.R. China
2. Central Laboratory, The First People's Hospital of Taicang, Taicang Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215400, P.R. China
3. Department of Pathology, University of Oklahoma Health Science Center, Oklahoma City, OK 73104, USA