1. Queen Mary College, Nanchang University, Nanchang, Jiangxi 330031, P.R. China
2. Key Laboratory of Endemic and Ethnic Diseases, Ministry of Education, Guizhou Medical University, Guiyang, Guizhou 550002, P.R. China
3. Department of Neurosurgery, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi 330029, P.R. China
4. Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing 100070, P.R. China