Author,Title,Journal,ISSN,Publisher,Date,Volume,Number,Page,URL,URL(DOI) SAURWEIN-TEISSL M.,Lack of antibody production following immunization in old age : association with CD8(+)CD28(-) T cell clonal expansions and an imbalance in the production of Th1 and Th2 cytokines,J. Immunol.,,,2002,168,,5893,https://cir.nii.ac.jp/crid/1570009750337570432,