1. Department of Ultrasound, North China University of Science and Technology Affiliated Hospital, Tangshan, Hebei, China
2. Department of Ultrasound, The Third Central Hospital of Tianjin, Tianjin, China
3. Tianjin Institute of Hepatobiliary Disease, Tianjin, China
4. College of Stomatology, Tianjin Medical University, Tianjin, China