[1] Tokyo Univ Hosp, Dept Neurol, Bunkyo Ku, Tokyo 1138655, Japan
[2] Fukushima Med Univ, Dept Neurol, Sch Med, Fukushima, Japan
[3] Natl Inst Publ Hlth, Dept Environm Hlth, Saitama, Japan
[4] Natl Inst Informat & Commun Technol, EMC Grp, Appl Electromagnet Res Ctr, Tokyo, Japan
[5] Kawamura Gakuen Womens Univ, Dept Educ, Chiba, Japan
[6] Natl Inst Publ Hlth, Dept Publ Hlth Policy, Saitama, Japan
[7] Kobe Univ, Sch Law, Kobe, Hyogo 657, Japan
[8] Tokyo Metropolitan Univ, Dept Elect & Elect Engn, Tokyo 158, Japan
[9] Meiji Pharmaceut Univ, Grad Sch Pharmaceut Sci, Dept Environm Biol, Tokyo, Japan