1. Department of Neurosurgery and Laboratory of Neurosurgery; Lanzhou University Second Hospital; Lanzhou, 730030 Gansu China
2. Institute of Neurology, Lanzhou University; Lanzhou, 730030 Gansu China
3. Department of Pediatric Neurology; Gansu Provincial Maternity and Child-care Hospital; Lanzhou, 730050 Gansu China