Objective To compare the effects of resuscitation at pure oxygen environment(100% oxygen) or room air environment(21% oxygen) on the ultrastructure of cerebral cortical neurons in hypoxic neonatal rat.Methods Twenty Sprague-Dawley neonatal rats aged 7 days were divided into the pure oxygen environment(POE) and room air environment groups(RAE) after hypoxia,and each group was divided again into 24 h and 72 h subgroups.The pups were placed in an incubator containing 8% O_2 to be at acute hypoxia continued for...