1. Department of Anesthesia, Jingzhou Central Hospital, The Second Clinical Medical College, Yangtze University, Jingzhou, Hubei, P.R. China
2. Department of Anesthesia, Benxi Central Hospital, Benxi, Liaoning, P.R. China
3. Department of Anesthesia, Weihai Municipal Hospital, Weihai, Shandong, P.R. China
4. Department of Pharmacology, Health Science Center, Yangtze University, Jingzhou, Hubei, P.R. China