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The first documented use of surgical anesthesia in the United States was in Connecticut in 1844.
The immune system needs 9.5 hours of sleep in total darkness to recharge completely.
There are over 65,000 known species of protozoa. About 10,000 species are parasitic.
People about to have surgery must tell their health care providers about all supplements they take.
In 2012, nearly 24 milliion Americans, aged 12 and older, had abused an illicit drug, according to the National Institute on Drug Abuse (NIDA).
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