1. Department of Neurology, Second Hospital of Hebei Medical University, Shijiazhuang, Hebei, China
2. The Key Laboratory of Clinical Neurology, Ministry of Education, Shijiazhuang, Hebei, China
3. Key Laboratory of Neurology of Hebei Province, Shijiazhuang, Hebei, China, and
4. Department of Neurology, Cangzhou Central Hospital, Cangzhou, Hebei, China