1. Department of Neurosurgery, Beijing Ditan Hospital, Capital Medical University, Beijing 100015, P.R. China
2. Department of Neurosurgery, Beijing Ditan Hospital, Capital Medical University, Beijing 100015, P.R. China
3. National Center for Infectious Disease, Beijing Ditan Hospital, Capital Medical University, Beijing 100015, P.R. China
4. National Center for Infectious Disease, Beijing Ditan Hospital, Capital Medical University, Beijing 100015, P.R. China