About the Authors
Department of Respiratory Medicine, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
Department of Respiratory Medicine, Yijishan Hospital of Wannan Medical College, Wuhu, China
The authors have declared that no competing interests exist.
Conceived and designed the experiments: CJ HH ZX. Performed the experiments: CJ HH JL YW. Analyzed the data: CJ HH ZL. Contributed reagents/materials/analysis tools: CJ HH. Wrote the paper: CJ HH ZX.