Dr. Li Nan graduated from the Department of clinical medicine of Beijing Medical University in 1995 and obtained his doctor's degree from Beijing University in 2001. Since 1995, she has worked in the Department of respiratory and critical care medicine, the first hospital of Peking University. She is a young member of the public health branch of the Chinese Medical Association, a member of the respiratory and interventional branch of the Beijing Medical Association, a member of the Beijing Working Group on chronic obstructive pulmonary disease, and a tour lecturer of "gina-aria Chinese doctor training program" for asthma. Editorial board of International Journal of respiration. During 2005-2007, she conducted clinical research on asthma in Copenhagen University Hospital, Denmark. She has rich clinical experience in the diagnosis and treatment of common respiratory diseases such as asthma and COPD.