1. Department of Oncology, Affiliated Hospital of Hebei University, Baoding, Hebei 071000, P.R. China
2. Department of Functions Branch, Affiliated Hospital of Hebei University, Baoding, Hebei 071000, P.R. China
3. Department of Surgery, Baoding No.1 Central Hospital, Baoding, Hebei 071000, P.R. China
4. Department of Surgery, Affiliated Hospital of Hebei University, Baoding, Hebei 071000, P.R. China