[1] Yokohama City Univ, Sch Med, Dept Publ Hlth, Yokohama, Kanagawa 2360004, Japan
[2] Tottori Univ, Fac Med, Dept Hyg, Yonago, Tottori 683, Japan
[3] Aichi Canc Ctr, Res Inst, Nagoya, Aichi 464, Japan
[4] Yokohama City Univ, Sch Med, Dept Clin Lab, Yokohama, Kanagawa 2360004, Japan
[5] Yokohama City Inst Hlth, Yokohama, Kanagawa, Japan