title: Longitudinal study of the radiology of coal workers' pneumoconiosis. I. Small and large opacities.
mesh_terms: D000328:Adult; D003032:Coal Mining; D006801:Humans; D008137:Longitudinal Studies; D008168:Lung / Q000000981:diagnostic imaging; D008875:Middle Aged; D011009:Pneumoconiosis / Q000145:classification / Q000000981:diagnostic imaging*; D011859:Radiography