title: The effect of age on the distribution of ventilation and perfusion in the lung.
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging; D000403:Airway Resistance; D006801:Humans; D008168:Lung / Q000502:physiology*; D008173:Lung Diseases, Obstructive / Q000503:physiopathology*; D008875:Middle Aged; D011652:Pulmonary Circulation; D012123:Pulmonary Ventilation; D011868:Radioisotopes; D011877:Radionuclide Imaging; D012119:Respiration; D013147:Spirometry; D014692:Ventilation-Perfusion Ratio; D014978:Xenon
chemical_list: D011868:Radioisotopes; D014978:Xenon