1. First Department of Medicine; Hokkaido University School of Medicine; Sapporo Japan
2. Department of Respiratory Medicine; National Hospital Organization Hokkaido Medical Center; Sapporo Japan
3. Department of Respiratory Medicine; JR Sapporo Hospital; Sapporo Japan
4. Ohmichi Clinic of Internal and Respiratory Medicine; Sapporo Japan
5. Shinjuku Kaijo Building Clinic; Tokyo Japan