1. Department of Neurology, Dongying People's Hospital, Dongcheng, Shandong 257091, P.R. China
2. Digestive Endoscopy Center, Dongying People's Hospital, Dongcheng, Shandong 257091, P.R. China
3. Department of Health Care, Dongying People's Hospital, Dongcheng, Shandong 257091, P.R. China