1. Clinical Research Center, National Hospital Organization Nagasaki Medical Center, Nagasaki, Japan
2. Clinical Research Center, National Hospital Organization Kyushu Medical Center, Fukuoka, Japan
3. Center for Liver Diseases, National Hospital Organization Kokura Medical Center, Kitakyushu, Japan
4. Clinical Research Center, National Hospital Organization Nagasaki Medical Center
5. Clinical Research Center, National Hospital Organization Kyushu Medical Center, Fukuoka, Japan and Health Care Center Clinic, Fukuoka University, Fukuoka, Japan