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Vaccines prevent between 2.5 and 4 million deaths every year.
In 1844, Charles Goodyear obtained the first patent for a rubber condom.
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.
On average, the stomach produces 2 L of hydrochloric acid per day.
The word drug comes from the Dutch word droog (meaning "dry"). For centuries, most drugs came from dried plants, hence the name.
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