1. Cardiovascular Division, Beth Israel Deaconess Medical
Center, Harvard Medical School, Boston, Massachusetts 02215, United States
2. Department of Polymer Engineering, Sunchon National University, Sunchon, Chonnam 540-950, Korea
3. Advanced Radiation Technology Institute, Atomic Energy Research Institute, Jeongeup, Chonbuk 580-185, Korea
4. Department of Nuclear Medicine, Seoul National University College of Medicine, Seoul 151-742, Korea