1. Department of Neurosurgery; Xuanwu Hospital, Capital Medical University; Beijing China
2. Medical Library of Xuanwu Hospital; Xuanwu Hospital, Capital Medical University; Beijing China
3. Department of Evidence-based Medicine; Xuanwu Hospital, Capital Medical University; Beijing China
4. Neurosciences; Essentia Health, St Mary's Medical Center; Duluth Minnesota USA
5. Neurosciences, Stroke and Cerebrovascular; CentraCare Health System; St Cloud Minnesota USA
6. Department of Anesthesiology; Beijing Obstetrics and Gynecology Hospital, Capital Medical University; Beijing China