1 Department of Emergency, Xiangya Hospital, Central South University, Changsha 410008, Hunan Province, China.
2 Department of Neurology, Xiangya Hospital, Central South University, Changsha 410008, Hunan Province, China.
3 Department of Emergency, Xiangya Hospital, Central South University, Changsha 410008, Hunan Province, China. Electronic address: lixiaogang_xy@163.com.