1. State Key Laboratory of Respiratory Diseases, Guangzhou Institute of Respiratory Disease, Guangzhou, China;
2. Emergency Department, The Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, China;
3. Division of Pulmonary and Critical Care Medicine, Johns Hopkins Medical Institutions, Baltimore, Maryland; and
4. Department of Laboratory Medicine, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China;
5. Fu Wai Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China