The absorption by a tissue of some substance, food material, mineral, etc., and its permanent or temporary retention.
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up·take 'əp-.tāk n an act or instance of absorbing and incorporating something esp. into a living organism, tissue, or cell <oxygen \uptake> <thyroid function should be determined by radioiodine \uptake studies (Jour. Amer. Med. Assoc.)>
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up·take (upґtāk) absorption and incorporation of a substance by living tissue.Medical dictionary. 2011.