[1] Shandong Univ, Inst Resp Monitoring & Support, Jinan 250012, Shandong, Peoples R China
[2] Shandong Univ, Sch Nursing & Rehabil, Jinan 250012, Shandong, Peoples R China
[3] Shandong Univ, Sch Stomatol, Jinan 250012, Shandong, Peoples R China
[4] Shandong Univ, Qilu Hosp, Dept Pulm & Crit Care Med, Jinan 250012, Shandong, Peoples R China