1. Department of Endocrinology, Hematology, and Gerontology, Chiba University Graduate School of Medicine, Chiba 260-8670, Japan.
2. Department of Diabetes, Metabolism and Endocrinology, School of Medicine, International University of Health and Welfare, 4-3 Kozunomori, Narita-shi, Chiba 286-8686, Japan.
3. Yu-karigaoka Tokuyama Clinic, 7-2-2 Nishi yu-karigaoka, Sakura-shi, Chiba 265-0850, Japan.
4. Department of Orthopaedics, Asahi Chuo Hospital, Asahi-shi, Chiba, 289-2511, Japan
5. Department of Metabolism and Endocrinology, Eastern Chiba Medical Center, Togane-shi, Chiba, 283-8686, Japan
6. Department of Diabetes and Metabolism, Asahi Chuo Hospital, Chiba, Asahi-shi, Japan