Association of Serum Retinol Concentrations With Metabolic Syndrome Components in Iranian Children and Adolescents: The CASPIAN-V Study oleh Mostafa Qorbani, Mostafa Qorbani, Ehsan Seif, Ramin Heshmat, Zahra Nouri Ghonbalani, Pouria Basiry, Elham Kazemian, Roya Kelishadi