1. Department of Medical Ultrasound, Shanghai Tenth People’s Hospital, School of Medicine, Tongji University, 301 Yan-chang-zhong Road, Shanghai 200072, P. R. China
2. A Guangxi Collaborative Innovation Center for Biomedicine, and Affiliated Tumor Hospital of Guangxi Medical University, Guangxi Medical University, 22 Shuang Yong Road, Nanning, Guangxi 530021, P. R. China
3. Department of Medical Ultrasound, Shanghai General Hospital, Shanghai Jiaotong University School of Medicine, 85 Wu-jin Road, Shanghai 200080, P. R. China