[1] Natl Clin Res Ctr Resp Dis, Beijing 100029, Peoples R China
[2] China Japan Friendship Hosp, Ctr Resp Dis, Beijing 100029, Peoples R China
[3] China Japan Friendship Hosp, Dept Pulm & Crit Care Med, Beijing 100029, Peoples R China
[4] China Japan Friendship Hosp, Dept Rheumatol, Beijing 100029, Peoples R China
[5] Henan Univ, Dept Resp Med, Affiliated Hosp 1, Kaifeng, Peoples R China