Selenium, a metalloid mineral micronutrient,is an essential component for the adequate and healthy life of human, animals, and some other microorganisms.Selenium has antioxidative and oxidative effects on living organisms.Selenium deficiency has been associated with impaired function of the immune system.Selenium deficiency appears to enhance the virulence or progression of some viral infections.Selenium deficiency results in decreased activity of glutathione peroxidase, increasing oxidative damage and the likelihood of mutations in the viral genome.The safe range of selenium intake is relatively small and excess selenium intake can readily result in toxicity.This review summarizes the updates of benefitial and adverse effects of selenium on health.

PurposeTo explore and compare subtracted and unsubtracted volume rendering process on DSA apparatus in the diagnosis and treatment of intracranial aneurysms, and to provide a better reconstruction in clinic.Materials and Methods Twenty-seven patients with subarachnoid hemorrhage (SAH) underwent rotational cerebral angiography and 19 cases with embolization treatment underwent rotational cerebral angiography follow-up. 3D volume unsubtracted reconstruction and subtracted reconstructions were used respectively. Two sets of 3D volume reconstruction images were observed and analyzed by two neuroradiologists to compare the detection rate, image quality and post-embolization follow up.Results Thirty-three intracranial aneurysms were identiifed in 27 cases with SAH underwent three-dimensional digital angiography (3D-DA). False positives were found in 2 cases. 3D-DSA detected 33 intracranial aneurysms with no false positive case. There was no statistical signiifcance in intracranial aneurysms detection rate (χ2=1.943,P>0.05). There was no statistical significance in image quality of two reconstruction methods (Z=-1.445,P>0.05). In 19 cases with embolization treatment underwent the follow-up of rotational cerebral angiography, 3D-DA detected 3 cases with aneurysm remnants, while 3D-DSA detected 10. There was statistical signiifcance between 3D-DA and 3D-DSA when detecting aneurysm remnant (χ2=5.729,P<0.05).Conclusion Aneurysms can be well detected with better image quality by 3D-DSA and 3D-DA in the diagnosis and treatment of intracranial aneurysms. 3D-DSA can display more information on tiny vessels, and is better in detecting aneurysm remnants.