Alterations in the plasma levels of NOx (A), ADMA (B), TBARS (C), sFasL (D), and CD40L (E) in each group. Abbreviations: ADMA, asymmetrical dimethylarginine; CD40L, soluble CD40 ligand; CPAP, continuous positive airway pressure; NOx, nitric oxide compounds; sFasL, soluble Fas ligand; TBARS, thiobarbituric acid reactive substance. *P < 0.05, **P < 0.01.