title: Variation in the levels of serum constituents in childhood.
mesh_terms: D000293:Adolescent; D000375:Aging / Q000097:blood*; D001774:Blood Chemical Analysis; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D012737:Sex Factors