1. Department of Neurosurgery , XiangYa Hospital, , Changsha, 410008 , China
2. Central South University , XiangYa Hospital, , Changsha, 410008 , China
3. Department of Pharmacology, Kyoto University Graduate School of Medicine , Kyoto, 606-8501 , Japan
4. Department of Epidemiology and Health Statistics , XiangYa School of Public Health, , Changsha, 410078 , China
5. Central South University , XiangYa School of Public Health, , Changsha, 410078 , China
6. Department of Neurology, Hunan Province People’s Hospital (The First Affiliated Hospital of Hunan Normal University) , Changsha, 410005 , China
7. Hunan Provincial Key Laboratory of Clinical Epidemiology , XiangYa School of Public Health, , Changsha, 410078 , China