The horizontal fraction bar was introduced by the Arabs.
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The familiar sounds of your heart are made by the heart's valves as they open and close.
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Cocaine was isolated in 1860 and first used as a local anesthetic in 1884. Its first clinical use was by Sigmund Freud to wean a patient from morphine addiction. The fictional character Sherlock Holmes was supposed to be addicted to cocaine by injection.
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The average human gut is home to perhaps 500 to 1,000 different species of bacteria.
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The term pharmacology is derived from the Greek words pharmakon("claim, medicine, poison, or remedy") and logos ("study").
Common arachnids.
Diverse living organisms share common chemical features
Large families on U.S. farms used to be common. Children helped plant and harvest crops, take care ...