title: The effects of opium smoking in cigarette smokers.
mesh_terms: D000328:Adult; D000402:Airway Obstruction / Q000139:chemically induced*; D006801:Humans; D008173:Lung Diseases, Obstructive / Q000139:chemically induced; D008297:Male; D008875:Middle Aged; D009892:Opium; D012129:Respiratory Function Tests; D012907:Smoking / Q000150:complications*; D019966:Substance-Related Disorders / Q000150:complications*; D014692:Ventilation-Perfusion Ratio; D014797:Vital Capacity
chemical_list: D009892:Opium