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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.
Thyroid conditions cause a higher risk of fibromyalgia and chronic fatigue syndrome.
Medication errors are three times higher among children and infants than with adults.
There are over 65,000 known species of protozoa. About 10,000 species are parasitic.
The Romans did not use numerals to indicate fractions but instead used words to indicate parts of a whole.
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