Dormandy T L
Ann R Coll Surg Engl. 1980 May;62(3):188-94.
Free radicals are a highly reactive chemical species which differ from all other species in possessing an unpaired electron. Although free-radical activity in living systems is energetically improbable, recent work suggests that a number of important biological processes depend on it. In contrast to enzymic metabolism these free-radical processes tend to be non-cyclic, irreversible, non-homoeostatic, and energetically wasteful. For the organism as a whole they may nevertheless have considerable survival value. Free radicals are too short-lived to be demonstrable in tissues; but methodological advances are leading to the detection and measurement of characteristic free-radical reaction products. The findings suggest that free-radical activity is not only a potential cause but also a common, perhaps invariable, consequence of cell damage. It is possible that some of the secondary products of free-radical reactions may help to regulate the body's local and systemic response to injury.
自由基是一种具有高度反应活性的化学物质，它与所有其他物质的不同之处在于拥有一个未配对电子。尽管生物系统中的自由基活性在能量上不太可能发生，但最近的研究表明，许多重要的生物过程都依赖于它。与酶促代谢不同，这些自由基过程往往是非循环的、不可逆的、非稳态的，并且在能量上是浪费的。然而，对于整个生物体来说，它们可能具有相当大的生存价值。自由基寿命太短，无法在组织中被检测到；但方法学的进步正导致对特征性自由基反应产物的检测和测量。研究结果表明，自由基活性不仅是细胞损伤的潜在原因，也是细胞损伤常见的、甚至可能是必然的结果。自由基反应的一些次级产物可能有助于调节身体对损伤的局部和全身反应。
