[1] Fukuoka Univ, Sch Med, Dept Internal Med 1, Jonan Ku, Fukuoka 8140180, Japan
[2] Fukuoka Univ, Sch Med, Dept Neurosurg, Jonan Ku, Fukuoka 8140180, Japan
[3] Fukuoka Univ, Sch Med, Dept Pathol 1, Jonan Ku, Fukuoka 8140180, Japan
[4] Hamanoumachi Hosp, Fukuoka, Japan
[5] Univ Occupat & Environm Hlth, Dept Internal Med 1, Kitakyushu, Fukuoka 807, Japan