1 Division of Laboratory and Transfusion Medicine, Hokkaido University Hospital, Sapporo, Japan; Department of Medical Technology and Sciences, School of Health Sciences at Narita, International University of Health and Welfare, Chiba, Japan.
2 Division of Laboratory and Transfusion Medicine, Hokkaido University Hospital, Sapporo, Japan. Electronic address: sugitaj@med.hokudai.ac.jp.
3 Department of Medical Technology and Sciences, School of Health Sciences at Narita, International University of Health and Welfare, Chiba, Japan.
4 Division of Laboratory and Transfusion Medicine, Hokkaido University Hospital, Sapporo, Japan.