1. Seoul National University College of Medicine, Seoul, Korea.
2. Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
3. Department of Internal Medicine, National Medical Center, Seoul, Korea.
4. Department of Pathology, Seoul National University College of Medicine, Seoul, Korea.
5. Hansung Science High School, Seoul, Korea.
6. Biomedical Research Institute, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea.
7. Department of Surgery, Seoul National University College of Medicine, Seoul, Korea.
8. Department of Surgery, National Medical Center, Seoul, Korea.