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In 1844, Charles Goodyear obtained the first patent for a rubber condom.
Many of the drugs used by neuroscientists are derived from toxic plants and venomous animals (such as snakes, spiders, snails, and puffer fish).
The first-known contraceptive was crocodile dung, used in Egypt in 2000 BC. Condoms were also reportedly used, made of animal bladders or intestines.
After a vasectomy, it takes about 12 ejaculations to clear out sperm that were already beyond the blocked area.
Increased intake of vitamin D has been shown to reduce fractures up to 25% in older people.
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