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More than 2,500 barbiturates have been synthesized. At the height of their popularity, about 50 were marketed for human use.
Long-term mental and physical effects from substance abuse include: paranoia, psychosis, immune deficiencies, and organ damage.
There are over 65,000 known species of protozoa. About 10,000 species are parasitic.
People with high total cholesterol have about two times the risk for heart disease as people with ideal levels.
Egg cells are about the size of a grain of sand. They are formed inside of a female's ovaries before she is even born.
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