1. Department of Neurosurgery, Beijing Sanbo Brain Hospital, Capital Medical University, Beijing 100093, P.R. China
2. Department of Neurosurgery, The First Hospital of China Medical University, Shenyang 110001, P.R. China
3. Beijing Key Laboratory of Neural Regeneration and Repair, Department of Neurobiology, Capital Medical University, Beijing 100069, P.R. China