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There are over 65,000 known species of protozoa. About 10,000 species are parasitic.
Thyroid conditions cause a higher risk of fibromyalgia and chronic fatigue syndrome.
Illicit drug use costs the United States approximately $181 billion every year.
Your heart beats over 36 million times a year.
There are more nerve cells in one human brain than there are stars in the Milky Way.
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