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Human kidneys will clean about 1 million gallons of blood in an average lifetime.
There are approximately 3 million unintended pregnancies in the United States each year.
The immune system needs 9.5 hours of sleep in total darkness to recharge completely.
Fungal nail infections account for up to 30% of all skin infections. They affect 5% of the general population—mostly people over the age of 70.
About 100 new prescription or over-the-counter drugs come into the U.S. market every year.
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