title: Letter: Age dependence of T-cells.
mesh_terms: D000293:Adolescent; D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D006801:Humans; D007104:Immune Adherence Reaction; D007111:Immunity, Cellular; D007223:Infant; D007958:Leukocyte Count; D013601:T-Lymphocytes