[Long-term observation on occupational deafness].
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D001299:Audiometry; D003638:Deafness / Q000517:prevention & control; D005500:Follow-Up Studies; D006801:Humans; D008875:Middle Aged; D008906:Mining; D009622:Noise; D009784:Occupational Diseases; D013997:Time Factors