[1] Peking Univ, Peoples Hosp, Dept Resp & Crit Care Med, Beijing 100044, Peoples R China
[2] Huazhong Univ Sci & Technol, Dept Resp Med, Affiliated Union Hosp, Wuhan 430022, Hubei, Peoples R China
[3] Tsinghua Univ, Affiliated Hosp 1, Dept Resp Med, Beijing 100016, Peoples R China
[4] Guizhou Prov Peoples Hosp, Dept Resp & Crit Care Med, Guiyang 550002, Guizhou, Peoples R China