Cihan Berat H, Çolak  C, Nisanoğlu  V, Öztürk  Ç, Öztürk  F, Erdil  N, et al. The role of antioxidant enzymes and 6-sulphatoxymelatonin in radial artery atherosclerosis. Turk Gogus Kalp Dama 2008;16:216-222