1. Department of Gerontology
2. Affiliated Hospital of Jiangsu University
3. Zhenjiang 212001
4. China
5. Institute of Life Sciences
6. Jiangsu University
7. Zhenjiang 212013
8. P. R. China
9. P. E. Department of Jiangsu University
10. Department of Obstetrics and Gynecology
11. The Fourth People's Hospital of Zhenjiang
12. Zhenjiang