1. Department of Respiratory Medicine, Shikoku Central Hospital of the Mutual aid Association of Public School teachers, Shikoku-Chuo, Japan
2. Department of Respiratory Medicine and Rheumatology, Graduate School of Biomedical Sciences, Tokushima University, Tokushima, Japan
3. Department of Cardiovascular Surgery, Shikoku Central Hospital of the Mutual aid Association of Public School teachers, Shikoku-Chuo, Japan