1. Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology , Wuhan, Hubei, P. R. China
2. Department of Clinical Laboratory, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology , Wuhan, Hubei, P. R. China
3. Department of General Surgery, Affiliated Hospital of Yangzhou University , Yangzhou, Jiangsu, P. R. China