1. Department of General Surgery, Affiliated Changsha Hospital of Hunan Normal University, Changsha, Hunan 410006, P.R. China
2. Department of Neurology, China‑Japan Union Hospital of Jilin University, Changchun, Jilin 130013, P.R. China
3. Department of General Surgery, Third Hospital of Changsha, Changsha, Hunan 410015, P.R. China