title: Use of  13 N in studies of airway closure and regional ventilation.
mesh_terms: D000328:Adult; D000402:Airway Obstruction / Q000175:diagnosis* / Q000503:physiopathology; D002849:Chromatography, Gas; D005260:Female; D006207:Half-Life; D006801:Humans; D008297:Male; D008722:Methods; D009584:Nitrogen; D009587:Nitrogen Isotopes; D012123:Pulmonary Ventilation; D011868:Radioisotopes; D012119:Respiration; D012129:Respiratory Function Tests; D013147:Spirometry
chemical_list: D009587:Nitrogen Isotopes; D011868:Radioisotopes; D009584:Nitrogen