1. Department of Obstetrics and Gynecology, Graduate School of Medical Sciences Kanazawa University Kanazawa Ishikawa 920‐8641 Japan
2. Department of Obstetrics and Gynecology, Public Central Hospital of Matto Ishikawa Hakusan Japan
3. Department of Obstetrics and Gynecology Tokyo Medical University Tokyo 160‐0023 Japan
4. Department of Virology II National Institute of Infectious Diseases Tokyo 162‐8640 Japan
5. Department of Obstetrics and Gynecology Shimane University Faculty of Medicine Izumo Shimane 693‐8501 Japan
6. Departments of Biochemistry and Molecular Vascular Biology Kanazawa University Graduate School of Medical Sciences Kanazawa Ishikawa 920‐8640 Japan
7. Division of Animal Disease Model, Research Center for Experimental Modeling of Human Disease Kanazawa University Kanazawa Ishikawa 920‐8640 Japan