title: [Seasonal rhythm in 25-hydroxyvitamin D blood levels].
abstract: A retrospective study of the serum concentrations of 25-hydroxyvitamin D was performed over a one-year period, using data from 158 healthy subjects aged 40-80 years. Serum 25-hydroxyvitamin D was determined by competitive protein binding assay; the method included a chromatographic step. A noticeable seasonal variation was observed, with a maximum in summer.
mesh_terms: D015652:25-Hydroxyvitamin D 2; D000328:Adult; D000368:Aged; D004872:Ergocalciferols / Q000031:analogs & derivatives* / Q000097:blood; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011869:Radioligand Assay; D012189:Retrospective Studies; D012621:Seasons
chemical_list: D004872:Ergocalciferols; D015652:25-Hydroxyvitamin D 2
vernacular_title: Dei livelli di 25-idrossivitamina D nel siero.