1. Department of Histology and Embryology, Xinxiang Medical University, Xinxiang, China.
2. The Clinical Laboratory, The First Affiliated Hospital of Xinxiang Medical University, Weihui, China.
3. Sanquan Medical College, Xinxiang Medical University, Xinxiang, China.
4. Endoscope Room, The First Affiliated Hospital of Xinxiang Medical University, Weihui, China.
5. Department of Radiation Medicine, The Fourth Military Medical University, Xi'an, China.