1. Asan Institute for Life Sciences, Asan Medical Center, Seoul 05505, Korea
2. Department of Convergence Medicine, University of Ulsan College of Medicine, Seoul 05505, Korea
3. Division of Hepatobiliary Surgery and Liver Transplantation, Department of Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505, Korea
4. Department of Pulmonary and Critical Care Medicine, Clinical Research Center for Chronic Obstructive Airway Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505, Korea