%0 Journal Article %T Especies reactivas del ox¨ªgeno y balance redox, parte I: aspectos b¨¢sicos y principales especies reactivas del ox¨ªgeno %A Mart¨ªnez S¨¢nchez %A Gregorio %J Revista Cubana de Farmacia %D 2005 %I ECIMED %X the redox balance has been increasingly recognized as a critical component of the aging process; the onset and development of diseases causing dramatic morbidity and mortality (atherosclerosis, cancer, central nervous system diseases, autoinmune diseases, ischemia-reperfusion damage, among others) and oxidative stress-induced cellular responses. closely related to oxidative stress is the generation of oxygen reactive species, which cause direct cell damage in addition to acting as second intracellular messengers when modulating signal transduction pathways. the present paper presented the main antecedents of pieces of research related to this topic and described the most important characteristics of the oxygen reactive species. %K oxidative stress %K free radicals %K oxygen reactive species. %U http://scielo.sld.cu/scielo.php?script=sci_abstract&pid=S0034-75152005000300009&lng=en&nrm=iso&tlng=en