title: Narcotic analgesics in the treatment of cancer and postoperative pain. Introduction.
mesh_terms: D006801:Humans; D009294:Narcotics / Q000627:therapeutic use*; D009369:Neoplasms / Q000150:complications*; D010148:Intractable Pain / Q000188:drug therapy* / Q000209:etiology; D010149:Postoperative Pain / Q000188:drug therapy*; D012106:Research
chemical_list: D009294:Narcotics