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In 1864, the first barbiturate (barbituric acid) was synthesized.
The Babylonians wrote numbers in a system that used 60 as the base value rather than the number 10. They did not have a symbol for "zero."
There are over 65,000 known species of protozoa. About 10,000 species are parasitic.
The longest a person has survived after a heart transplant is 24 years.
The human body produces and destroys 15 million blood cells every second.
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