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There are more bacteria in your mouth than there are people in the world.
In 1844, Charles Goodyear obtained the first patent for a rubber condom.
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."
The immune system needs 9.5 hours of sleep in total darkness to recharge completely.
Oliver Wendell Holmes is credited with introducing the words "anesthesia" and "anesthetic" into the English language in 1846.
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