1. Key Laboratory of Molecular Epidemiology of Hunan Province, Hunan Normal University, Changsha, 410013, Hunan, China
2. Department of Pneumoconiosis, Beidaihe Sanitarium for China Coal Miners, Beidaihe, 066100, Hebei, China
3. Key Laboratory of Molecular Epidemiology of Hunan Province, Hunan Normal University, No. 371 Tongzipo Road, Changsha, 410013, Hunan, China