1. Department of Neurosurgery, Haikou Affiliated Hospital of Central South University Xiangya School of Medicine Haikou, China.
2. Center for Clinical Sciences, National Center for Global Health and Medicine, Tokyo, Japan.
3. Department of Gastroenterology, Hainan Affiliated Hospital of Hainan Medical University, Haikou, China.
4. International Health Care Center, National Center for Global Health and Medicine, Tokyo, Japan.