1. Department of Anatomy, School of Basic Medical Sciences, Fujian Medical University, Fuzhou, Fujian 350004, P.R. China
2. Department of Histology and Embryology, Quanzhou Medical College, Quanzhou, Fujian 362100, P.R. China
3. Department of Medical Imaging, Quanzhou Medical College, Quanzhou, Fujian 362100, P.R. China
4. Department of Anatomy, Quanzhou Medical College, Quanzhou, Fujian 362100, P.R. China