[1] Kishiwada City Hosp, Div Hematol, Osaka 5968501, Japan
[2] Kansai Med Univ, Dept Internal Med 2, Moriguchi, Osaka 570, Japan
[3] Saiseikai Izuo Hosp, Dept Internal Med, Osaka, Japan
[4] Baba Mem Hosp, Dept Cardiol, Sakai, Osaka, Japan
[5] Tohou Kashiba Hosp, Dept Brain Surg, Kashiba, Japan