Source:http://linkedlifedata.com/resource/umls/id/C0016693
MSH: Highly reactive molecules with an unsatisfied electron valence pair. Free radicals are produced in both normal and pathological processes. They are proven or suspected agents of tissue damage in a wide variety of circumstances including radiation, damage from environment chemicals, and aging. Natural and pharmacological prevention of free radical damage is being actively investigated.,CSP: chemicals whose molecular or ionic structure includes an unpaired ("free") electron, usually conferring high reactivity; in biological systems, most free radicals contain oxygen (prefer FREE RADICAL OXYGEN).,NCI: A type of unstable molecule that is made during normal cell metabolism (chemical changes that take place in a cell). Free radicals can build up in cells and cause damage to other molecules, such as DNA, lipids, and proteins. This damage may increase the risk of cancer and other diseases.,NCI: Molecules or atoms with at least one unpaired or 'free' electron in the outermost electron shell. Chemically unstable,