1. Division of Cardiology, Pusan National University Hospital, Busan, Korea.
2. Medical Research Institute, Pusan National University Hospital, Busan, Korea.
3. Division of Thoracic Surgery, Pusan National University Hospital, Busan, Korea.
4. Division of Pathology, Pusan National University Hospital, Busan, Korea.
5. Division of Physiology, Pusan National University Hospital, Busan, Korea.