2AHMEDZAI S,BROOKS D. Transdermal fentanyl versus sustained release oral morphinein cancer pain:preference,efficacy, and quality of life[J]. J Pain Symptom Manage,1997,13(5):254-261.
3MEGENS A,ARTOIS K,VERMIERE J,et al.Comparison of the analgesic and intestinal effects of fentanyl and morphine rats [J]. J Pain Symptom Manage, 1998,15(4):253-258.