title: Effects of marker gas and method on closing volume.
mesh_terms: D000328:Adult; D000368:Aged; D001128:Argon; D005260:Female; D005459:Fluorides; D006371:Helium; D006801:Humans; D008176:Lung Volume Measurements; D008297:Male; D008875:Middle Aged; D009584:Nitrogen; D005741:Noble Gases; D012907:Smoking / Q000503:physiopathology; D013455:Sulfur
chemical_list: D005741:Noble Gases; D006371:Helium; D001128:Argon; D013455:Sulfur; D009584:Nitrogen; D005459:Fluorides