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The average human gut is home to perhaps 500 to 1,000 different species of bacteria.
The word drug comes from the Dutch word droog (meaning "dry"). For centuries, most drugs came from dried plants, hence the name.
Today, nearly 8 out of 10 pregnant women living with HIV (about 1.1 million), receive antiretrovirals.
On average, someone in the United States has a stroke about every 40 seconds. This is about 795,000 people per year.
Human kidneys will clean about 1 million gallons of blood in an average lifetime.
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