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Thyroid conditions may make getting pregnant impossible.
In the United States, an estimated 50 million unnecessary antibiotics are prescribed for viral respiratory infections.
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.
The average human gut is home to perhaps 500 to 1,000 different species of bacteria.
Many of the drugs used by neuroscientists are derived from toxic plants and venomous animals (such as snakes, spiders, snails, and puffer fish).
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