1. Department of Otolaryngology-Head and Neck Surgery, the Affiliated Hospital of Qingdao University, Qingdao University, Qingdao, China
2. Department of Pathology, Shandong First Medical University, Jinan, Shandong, China
3. Organ Transplantation Center, the Affiliated Hospital of Qingdao University, Qingdao University, Qingdao, China
4. Key Laboratory of Otolaryngology-Head and Neck Surgery, Medical Research Center, the Affiliated Hospital of Qingdao University, Qingdao, China