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Egg cells are about the size of a grain of sand. They are formed inside of a female's ovaries before she is even born.
In 1864, the first barbiturate (barbituric acid) was synthesized.
Cancer has been around as long as humankind, but only in the second half of the twentieth century did the number of cancer cases explode.
Pubic lice (crabs) are usually spread through sexual contact. You cannot catch them by using a public toilet.
Between 1999 and 2012, American adults with high total cholesterol decreased from 18.3% to 12.9%
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