[The epidemiological investigation of pneumoconiosis in 13 professions in Sichuan province].
D000874:Anthracosilicosis / Q000453:epidemiology; D002681:China; D006801:Humans; D011009:Pneumoconiosis / Q000453:epidemiology* / Q000517:prevention & control; D012806:Siderosis / Q000453:epidemiology; D011795:Surveys and Questionnaires