1. Department of Surgery, Keimyung University Dongsan Medical Center, Keimyung University School of Medicine, Daegu, Korea.
2. Department of Internal Medicine, Kyungpook National University Hospital, Kyungpook National University School of Medicine, Daegu, Korea.
3. Department of Internal Medicine, Inje University Busan Paik Hospital, Inje University College of Medicine, Busan, Korea.
4. Department of Surgery, Chonnam National University Hospital, Chonnam National University Medical School, Gwangju, Korea.
5. Department of Internal Medicine, Chonbuk National University Hospital, Chonbuk National University Medical School, Jeonju, Korea.
6. Department of Surgery, Chonbuk National University Hospital, Chonbuk National University Medical School, Jeonju, Korea.