[1] Beijing Univ Chinese Med, Beijing, Peoples R China
[2] China Japan Friendship Hosp, Natl Ctr Resp Med, Natl Clin Res Ctr Resp Dis, Ctr Resp Med,Dept Pulm & Crit Care Med, Beijing 100029, Peoples R China
[3] Chinese Acad Med Sci, Inst Resp Med, Beijing, Peoples R China
[4] Tsinghua Univ, Sch Med, Beijing, Peoples R China
[5] Tsinghua Univ Peking Univ Joint Ctr Life Sci, Beijing, Peoples R China
[6] Capital Med Univ, Dept Resp Med, Beijing, Peoples R China