MedlinePlus Medical Encyclopedia: Ions

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Ions

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Alternative Names	Definition

Alternative Names

Cations; Anions

Definition Return to top

An ion is an atom or group of atoms that has an electric charge. Ions with a positive charge are called cations. Ions with a negative charge are called anions.

Ions can be created using radiation such as x-rays. Ionizing radiation is often used for diagnostic or therapeutic procedures, since the ions that are produced can be used to scan for or treat some diseases.

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Update Date: 7/18/2007

Updated by: Stuart Bentley-Hibbert, M.D., Ph.D., Department of Radiology, Weill Cornell Medical Center, New York, NY. Review provided by VeriMed Healthcare Network.

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