Presents basic, chemical, biological, and medical studies of free radicals on different targets and the consequences of their reactivity-covering the chemistry and biochemistry of free radicals, free radicals as second messengers that group the activation of transcription factors and enzymes, the importance of the antioxidant system in cell metabolism regulation, and the role of free radicals and antioxidants in disease management. Written by over 200 international authorities, the book offers incisive discussions on the significance of oxidant-antioxidant balance and cytotoxicity of free radicals when produced in excess by several sources, specifically radiation hydrogen peroxide as a stimulant of transcription factor NFkB leading to cell response against oxidative stress activation by hydrogen peroxide, radiation, and NO in fibroblasts, lymphocytes, endothelial cells, and other cell lines and of tyrosine kinases, phosphatases, and MAP kinases regulation of cell metabolism by endogenous antioxidants features of flavonoids and other exogenous antioxidants in cell protection as well as free radicals and antioxidants in cell apoptosis the involvement of free radicals in and the effect of antioxidants on the treatment of diseases and more.