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The familiar sounds of your heart are made by the heart's valves as they open and close.
Fungal nail infections account for up to 30% of all skin infections. They affect 5% of the general population—mostly people over the age of 70.
The Babylonians wrote numbers in a system that used 60 as the base value rather than the number 10. They did not have a symbol for "zero."
Malaria was not eliminated in the United States until 1951. The term eliminated means that no new cases arise in a country for 3 years.
Nearly 31 million adults in America have a total cholesterol level that is more than 240 mg per dL.
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