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There are over 65,000 known species of protozoa. About 10,000 species are parasitic.
Cancer has been around as long as humankind, but only in the second half of the twentieth century did the number of cancer cases explode.
There are 60,000 miles of blood vessels in every adult human.
The word drug comes from the Dutch word droog (meaning "dry"). For centuries, most drugs came from dried plants, hence the name.
Cucumber slices relieve headaches by tightening blood vessels, reducing blood flow to the area, and relieving pressure.
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