RT Journal Article SR Electronic T1 Preemptive Analgesic Effect on Postoperative Pain Management: Effect of Dextromethorphan JF Regional Anesthesia & Pain Medicine JO Reg Anesth Pain Med FD BMJ Publishing Group Ltd SP 30 OP 30 DO 10.1136/rapm-00115550-199924031-00030 VO 24 IS Suppl 1 A1 CS Wong YR 1999 UL http://rapm.bmj.com/content/24/Suppl_1/30.abstract AB