Influnce of etomidate on stress response and    early postoperative 
cognitive dysfunction in elderly orthopedic patients underwent totol introvenous anesthesia
ZHAN Hai-yan,PIAO Mei-hua,WANG Yan-shu,FENG Chun-sheng
Journal of Jilin University(Medicine Edition) . 2013, (5): 986 -990 .  DOI: DOI:10.7694/jldxyxb20130526