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caffeine    音标拼音: [kæf'in]
n. 咖啡因,茶精(兴奋剂)

咖啡因,茶精(兴奋剂)

caffeine
n 1: a bitter alkaloid found in coffee and tea that is
responsible for their stimulating effects [synonym: {caffeine},
{caffein}]

caffein \caf*fe"in\, Caffeine \Caf*fe"ine\, n. [Cf. F.
caf['e]ine. See {Coffee}.] (Chem.)
A white, bitter, crystallizable substance, found in coffee
and tea. It is identical with the alkaloid {theine} from tea
leaves, and with {guaranine} from guarana. It is responsible
for most of the stimulating effect of coffee or tea.
[1913 Webster WordNet 1.5]

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  • Caffeine - Wikipedia
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  • Caffeine - Uses, Side Effects, and More - WebMD
    Learn more about Caffeine uses, effectiveness, possible side effects, interactions, dosage, user ratings and products that contain Caffeine
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    Caffeine is a natural stimulant consumed throughout the world This article reviews caffeine and its health effects, both good and bad
  • Caffeine - The Nutrition Source
    Sources of Caffeine Caffeine is naturally found in the fruit, leaves, and beans of coffee, cacao, and guarana plants It is also added to beverages and supplements There is a risk of drinking excess amounts of caffeinated beverages like soda and energy drinks because they are taken chilled and are easy to digest quickly in large quantities
  • Caffeine | Stimulant, Health Benefits, Addiction | Britannica
    Caffeine, nitrogenous organic compound of the alkaloid group, substances that have marked physiological effects Caffeine occurs in tea, coffee, guarana, maté, kola nuts, and cacao Pure caffeine (trimethylxanthine) occurs as a white powder or as silky needles, which melt at 238 °C (460 °F); it
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    Learn how caffeine affects brain chemicals and health, sleep, and mood Understand safe daily limits, hidden sources, and signs you’re getting too much
  • Caffeine content for coffee, tea, soda and more - Mayo Clinic
    Find out how much caffeine is in coffee, tea, soda and energy drinks You may be getting more caffeine than you think you are
  • Caffeine - MedlinePlus
    What is caffeine? Caffeine is a bitter substance that occurs naturally in more than 60 plants including: Coffee beans Tea leaves Kola nuts, which are used to flavor soft drink colas Cacao pods, which are used to make chocolate products There is also synthetic (man-made) caffeine, which is added to some medicines, foods, and drinks For example, some pain relievers, cold medicines, and over-the





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