1. Second Department of Surgery, Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei 050011, P.R. China
2. Department of Pediatric Surgery, Second Hospital of Hebei Medical University, Shijiazhuang, Hebei 050000, P.R. China
3. Department of Oncology, Hebei General Hospital, Shijiazhuang, Hebei 050051, P.R. China
4. Research Center, Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei 050011, P.R. China