Affiliation: | 1. Department of Gastroenterological and Pediatric Surgery, Oita University Faculty of Medicine, Oita, Japan;2. Department of General Surgery, The First Hospital of Hebei Medical University, Hebei, China;3. Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine, Oita, Japan;4. Comprehensive Surgery for Community Medicine, Oita University Faculty of Medicine, Oita, Japan |