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There are over 65,000 known species of protozoa. About 10,000 species are parasitic.
This year, an estimated 1.4 million Americans will have a new or recurrent heart attack.
Asthma occurs in one in 11 children and in one in 12 adults. African Americans and Latinos have a higher risk for developing asthma than other groups.
If you could remove all of your skin, it would weigh up to 5 pounds.
Long-term mental and physical effects from substance abuse include: paranoia, psychosis, immune deficiencies, and organ damage.
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