1. Department of Neurosurgery, The Affiliated Renhe Hospital, China Three Gorges University, Yichang, Hubei 443000, P.R. China
2. Department of Neurology, Xinhua Hospital affiliated to Dalian University, Dalian, Liaoning 116021, P.R. China
3. Department of Neurosurgery, The First College of Clinical Medical Science, China Three Gorges University & Yichang Central People's Hospital, Yichang, Hubei 443003, P.R. China
4. Department of Gastroenterology, The Affiliated Renhe Hospital, China Three Gorges University, Yichang, Hubei 443000, P.R. China