[1] China Japan Friendship Hosp, Natl Clin Res Ctr Resp Dis, Dept Pulm & Crit Care Med, 2,East Yinghua Rd,Chaoyang Dist, Beijing 100029, Peoples R China
[2] Chinese Acad Med Sci, Inst Resp Med, Beijing, Peoples R China
[3] Peking Union Med Coll Hosp, Dept Resp & Crit Care Med, Beijing, Peoples R China
[4] Sichuan Univ, West China Hosp, Dept Resp & Crit Care Med, Chengdu, Peoples R China
[5] Peking Univ Third Hosp, Dept Resp & Crit Care Med, Beijing, Peoples R China
[6] Guangzhou Med Univ, Guangzhou Inst Resp Dis, Natl Clin Res Ctr Resp Dis, State Key Lab Resp Dis,Affiliated Hosp 1, Guangzhou, Peoples R China