1. Department of Gynaecology and Obstetrics; Beijing TongRen Hospital; Capital Medical University; Beijing; China
2. Department of Otolaryngology Head and Neck Surgery; Beijing TongRen Hospital; Capital Medical University; Beijing; China
3. Key Laboratory of Otolaryngology Head and Neck Surgery (Ministry of Education of China); Beijing Institute of Otolaryngology; Beijing; China
4. Johns Hopkins Asthma and Allergy Center; Division of Allergy and Clinical Immunology; Johns Hopkins University School of Medicine; Baltimore; MD; USA