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In 1864, the first barbiturate (barbituric acid) was synthesized.
There are over 65,000 known species of protozoa. About 10,000 species are parasitic.
Approximately 70% of expectant mothers report experiencing some symptoms of morning sickness during the first trimester of pregnancy.
In 1844, Charles Goodyear obtained the first patent for a rubber condom.
The immune system needs 9.5 hours of sleep in total darkness to recharge completely.
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