title: Pneumotachography by the ionization principle--a new approach.
mesh_terms: D002245:Carbon Dioxide; D008722:Methods; D009584:Nitrogen; D010100:Oxygen; D011827:Radiation; D012119:Respiration; D013147:Spirometry / Q000295:instrumentation
chemical_list: D002245:Carbon Dioxide; D009584:Nitrogen; D010100:Oxygen