1 Department of Rheumatology and Immunology, the Second Hospital of Hebei Medical University, No. 215, Heping West Road, Xinhua District, Shijiazhuang, 050000, Hebei Province, China.
2 Department of Rheumatology and Immunology, the Second Hospital of Hebei Medical University, No. 215, Heping West Road, Xinhua District, Shijiazhuang, 050000, Hebei Province, China. guohfch@126.com.