free radical


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free radical

n.
An atom or group of atoms that has at least one unpaired electron and is therefore unstable and highly reactive. In animal tissues, free radicals can damage cells and are believed to accelerate the progression of cancer, cardiovascular disease, and age-related diseases.

free radical

n
(Chemistry) an atom or group of atoms containing at least one unpaired electron and existing for a brief period of time before reacting to produce a stable molecule. Sometimes shortened to: radical Compare group10

free′ rad′ical


n.
a molecular fragment that bears one or more unpaired electrons and is therefore highly reactive.
[1895–1900]
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.free radical - an atom or group of atoms with at least one unpaired electron; in the body it is usually an oxygen molecule that has lost an electron and will stabilize itself by stealing an electron from a nearby molecule; "in the body free radicals are high-energy particles that ricochet wildly and damage cells"
atom - (physics and chemistry) the smallest component of an element having the chemical properties of the element
References in periodicals archive ?
The researchers exposed baby mice to a type of free radical found in air pollution, which triggered Ahr.
Hunting dogs are especially prone to free radical damage because of their ability and desire to go from sedentary to all-out in a matter of seconds.
Professor Siegfried Hekimi, a senior author of the study said that the belief that free radicals are damaging and cause aging is incorrect, and we have turned this so-called 'free radical theory of aging' theory on its head by proving that free radical production increases during aging thus inducing a substantially longer life.
We have turned this theory on its head by proving that free radical production increases during aging because free radicals actually combat -- not cause -- aging.
Once a free radical joins with an antioxidant, it is stable.
Now, about those skin creams with potentially harmful additives: topically applied products that contain high levels of allergens can increase free radical damage in your skin.
These thermodynamic properties can be used to predict a pecking order, or hierarchy, for free radical reactions.
When a free radical becomes oxidized, it turns into a pro-oxidant.
present 17 articles by Asian researchers working in free radical biology, gastroenterology, and hepatology who discuss the role of free radicals in digestive diseases such as pancreatitis, cancer, liver disease, hepatitis C, inflammatory bowel disease, drug-induced small intestinal injury, gastric mucosal injury, and infection, as well as the biology of free radicals, the role of biomarkers in monitoring the degree of disease and the design of new therapeutic strategies, and factors such as transition metal imbalance, lipid and glucose metabolic disturbance, mitochondria, oxidative stress and inflammation, and the interaction of gaseous molecules in producing free radicals.
Learning how to protect your brain against factors that contribute to free radical buildup may help you slow brain aging and resist diseases associated with oxidative damage.
Research approaches for explaining the effects of free radical exposure on protein structure are explored.
The content of this paper is to explore the effectiveness of tannins on the inhibition of free radicals and to discover the free radical scavenging abilities of tannins in unknown plant species.