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Thyroid conditions cause a higher risk of fibromyalgia and chronic fatigue syndrome.
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.
After a vasectomy, it takes about 12 ejaculations to clear out sperm that were already beyond the blocked area.
Human stomach acid is strong enough to dissolve small pieces of metal such as razor blades or staples.
The horizontal fraction bar was introduced by the Arabs.
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