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In 1844, Charles Goodyear obtained the first patent for a rubber condom.
This year, an estimated 1.4 million Americans will have a new or recurrent heart attack.
In the United States, there is a birth every 8 seconds, according to the U.S. Census Bureau's Population Clock.
In 1864, the first barbiturate (barbituric acid) was synthesized.
Egg cells are about the size of a grain of sand. They are formed inside of a female's ovaries before she is even born.
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