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In 1844, Charles Goodyear obtained the first patent for a rubber condom.
The familiar sounds of your heart are made by the heart's valves as they open and close.
Bacteria have been found alive in a lake buried one half mile under ice in Antarctica.
More than 34,000 trademarked medication names and more than 10,000 generic medication names are in use in the United States.
Vaccines prevent between 2.5 and 4 million deaths every year.
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