1. Department of Clinical Laboratory, Beijing Chao-Yang Hospital, Capital Medical University, Beijing 100020, China
2. Key Laboratory of Respiratory and Pulmonary Circulation Disorders, Institute of Respiratory Medicine, Beijing 100020, China
3. Department of Pulmonary and Critical Care Medicine, China-Japan Friendship Hospital, Beijing 100029, China
4. Department of Respiratory and Critical Care Medicine, Beijing Chao-Yang Hospital, Capital Medical University, Beijing 100020, China