1. Division of Medicine, Taoyuan Armed Forces General Hospital, Taoyuan 325, Taiwan
2. Division of Nephrology, Department of Internal Medicine, Taoyuan Armed Forces General Hospital Hsinchu Branch, Hsinchu 300, Taiwan
3. Division of Nephrology, Department of Internal Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei 114, Taiwan
4. Division of Nephrology, Department of Internal Medicine, Taoyuan Armed Forces General Hospital, Taoyuan 325, Taiwan
5. Department of Life Sciences, National Central University, Taoyuan 320, Taiwan