1. Department of Respiratory Medicine, Peking University Third Hospital, Beijing, China
2. State Key Laboratory of Respiratory Disease, National Clinical Research Center, Guangzhou Institute of Respiratory Disease, First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
3. Department of Pulmonary and Critical Care Medicine and Beijing Institute of Respiratory Medicine, Beijing Chao-Yang Hospital, Capital Medical University, Beijing, China
4. Department of Respiratory and Critical Care Medicine, Baogang Hospital, Third Affiliated Hospital of Inner Mongolia Medical College, Third School of Clinical Medicine, Inner Mongolia Regional Medical Center, Baotou, China
5. Department of Respiratory Medicine, Peking University Third Hospital, Beijing 100191, China