1. Faculty of Medicine and Graduate School of MedicineDepartment of Cardiovascular MedicineHokkaido UniversitySapporoJapan
2. Faculty of Health SciencesHokkaido UniversitySapporoJapan
3. Diagnostic Center for SonographyHokkaido University HospitalSapporoJapan
4. Faculty of Medicine and Graduate School of MedicineDepartment of Respiratory MedicineHokkaido UniversitySapporoJapan
5. Division of Clinical Laboratory and Transfusion MedicineHokkaido University HospitalSapporoJapan