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| A unit used to measure the activity of many vitamins, hormones, enzymes, and drugs. An International Unit is the amount of a substance that has a certain biological effect. For each substance there is an international agreement on the biological effect that is expected for 1 International Unit. Also called IU. |
Previous Definitions: | interleukin-6, interleukin-7, intermediate-grade lymphoma, internal examination, internal radiation therapy | Next Definitions: | interstitial radiation therapy, intervention, intervention group, intestinal, intestinal villi |
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