1. The Laboratory of Respiratory Disease, Affiliated Hospital of Guilin Medical University, Guilin 541001, Guangxi, China
2. School of Chemistry and Pharmaceutical Sciences, State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources, Guangxi Normal University, Guilin, 541004, P. R. China
3. Department of Respiratory Medicine, Affiliated Hospital of Guilin Medical University, Guilin 541001, Guangxi, China