1. Center of Gallbladder Disease, East Hospital of Tongji University, Shanghai 200120, P.R. China
2. Department of Hepatobiliary Surgery, The First People's Hospital of Hefei, Hefei, Anhui 230061, P.R. China
3. Department of Traditional Chinese Medicine, East Hospital of Tongji University, Shanghai 200120, P.R. China
4. Department of Ultrasonography, East Hospital of Tongji University, Shanghai 200120, P.R. China