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Aspirin is the most widely used drug in the world. It has even been recognized as such by the Guinness Book of World Records.
The first war in which wide-scale use of anesthetics occurred was the Civil War, and 80% of all wounds were in the extremities.
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.
Nearly 31 million adults in America have a total cholesterol level that is more than 240 mg per dL.
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