title: Tracheobronchial clearance in twins.
mesh_terms: D000328:Adult; D000336:Aerosols; D001345:Autoradiography; D001980:Bronchi / Q000502:physiology*; D002923:Cilia / Q000502:physiology; D003371:Cough; D005260:Female; D005465:Fluorocarbon Polymers; D006801:Humans; D008297:Male; D008875:Middle Aged; D011247:Pregnancy; D012129:Respiratory Function Tests; D012907:Smoking; D013667:Technetium; D013997:Time Factors; D014132:Trachea / Q000502:physiology*; D014427:Twins
chemical_list: D000336:Aerosols; D005465:Fluorocarbon Polymers; D013667:Technetium