1. Department of Respiratory and Critical Care Medicine; Beijing Chao-Yang Hospital; Capital Medical University; Beijing China
2. Beijing Key Laboratory of Respiratory and Pulmonary Circulation Disorders; Beijing Institute of Respiratory Medicine; Beijing China
3. Department of Infectious Diseases and Clinical Microbiology; Beijing Chao-Yang Hospital; Capital Medical University; Beijing China
4. Department of Critical Care Medicine; China-Japan Friendship Hospital; Ministry of Health; Beijing China
5. Institute of Respiratory Medicine; Beijing Hospital; Ministry of Health; Beijing China