1. Department of Surgery, Third Central Hospital of Tianjin, Third Central Clinical College of Tianjin Medical University, Tianjin Institute of Hepatobiliary Disease, Tianjin Key Laboratory of Artificial Cell, Artificial Cell Engineering Technology Research Center of Public Health Ministry, Tianjin, China.
2. Department of Ultrasonography, Tianjin Central Hospital of Gynecology and Obstetrics, Tianjin Medical University, Tianjin, China.