1. Department of Internal Medicine, Cheju National University Medical School, Jeju, South Korea
2. Chonnam National University Research Institute of Medical Sciences, Gwangju, South Korea
3. Department of Physiology, Chonnam National University Medical School, 5 Hak-dong, Gwangju 501-746, South Korea. Tel: +82 62 220 4262. Fax: +82 62 232 1242. E-mail: julee@chonnam.ac.kr