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The first-known contraceptive was crocodile dung, used in Egypt in 2000 BC. Condoms were also reportedly used, made of animal bladders or intestines.
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.
The first war in which wide-scale use of anesthetics occurred was the Civil War, and 80% of all wounds were in the extremities.
Increased intake of vitamin D has been shown to reduce fractures up to 25% in older people.
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