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There are 20 feet of blood vessels in each square inch of human skin.
In the United States, there is a birth every 8 seconds, according to the U.S. Census Bureau's Population Clock.
There are over 65,000 known species of protozoa. About 10,000 species are parasitic.
Blood in the urine can be a sign of a kidney stone, glomerulonephritis, or other kidney problems.
Thyroid conditions cause a higher risk of fibromyalgia and chronic fatigue syndrome.
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