title: Respiratory effects of butorphanol and pethidine.
mesh_terms: D000328:Adult; D002077:Butorphanol / Q000494:pharmacology*; D002245:Carbon Dioxide / Q000502:physiology; D006801:Humans; D008297:Male; D008614:Meperidine / Q000494:pharmacology*; D009019:Morphinans / Q000494:pharmacology*; D009270:Naloxone / Q000494:pharmacology; D010313:Partial Pressure; D010919:Placebos; D012119:Respiration / Q000187:drug effects*
chemical_list: D009019:Morphinans; D010919:Placebos; D002245:Carbon Dioxide; D009270:Naloxone; D008614:Meperidine; D002077:Butorphanol