1. Department of Radiology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kajii, Kawaramachi-Hirokoji, Kamigyo, Kyoto, Japan,
2. Department of Radiology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kajii, Kawaramachi-Hirokoji, Kamigyo, Kyoto, Japan
3. Department of Radiology, Kyoto First Red Cross Hospital, Motomachi, Higashiyama, Kyoto, Japan
4. Laboratory of Animal Reproduction, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido, Japan, Boya Farm, Aza-Kiyomi, Ikeda-cho, Hokkaido, Japan
5. Laboratory of Animal Reproduction, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido, Japan