1. State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China
2. Department of Pulmonary and Critical Care Medicine, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong, China
3. Key Laboratory of National Health Commission for the Diagnosis & Treatment of COPD, The People’s Hospital of Inner Mongolia Autonomous Region, Hohhot, Inner Mongolia, China