1. The First Affiliated Hospital, Department of Anorectal, Hengyang Medical School, University of South China, Hengyang, Hunan 421001, China
2. The First Affiliated Hospital, Emergency Medicine, Hengyang Medical School, University of South China, Hengyang, Hunan 421001, China
3. The First Affiliated Hospital, Department of Oncology, Hengyang Medical School, University of South China, Hengyang, Hunan 421001, China