1. Graduate School of Health Sciences, Gunma University, 3-39-22 Showa-machi, Mebashi, Gunma, Japan
2. Japan Atomic Energy Agency, Takasaki Advanced Radiation Research Institute, 1233 Watanuki-machi, Takasaki, Gunma, Japan
3. Takizawa Laboratory, Japan Radioisotope Association, 348-58 Tomegamori, Takizawa, Iwate, Japan
4. Cyclotron Research Center, Iwate Medical University, 348-58 Tomegamori, Takizawa, Iwate, Japan