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In 1844, Charles Goodyear obtained the first patent for a rubber condom.
There are 60,000 miles of blood vessels in every adult human.
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.
The most destructive flu epidemic of all times in recorded history occurred in 1918, with approximately 20 million deaths worldwide.
Elderly adults are living longer, and causes of death are shifting. At the same time, autopsy rates are at or near their lowest in history.
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