1. Department of Neurosurgery, Fujian Sanbo Funeng Brain Hospital, Fuzhou, Fujian 350001, P.R. China
2. Department of Oncology, Dongying People's Hospital, Dongying, Shandong 257000, P.R. China
3. Department of Pathology, Dongying People's Hospital, Dongying, Shandong 257000, P.R. China
4. Department of Orthopedics, Central Hospital of Zibo, Zibo, Shandong 255022, P.R. China