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There are over 65,000 known species of protozoa. About 10,000 species are parasitic.
Human stomach acid is strong enough to dissolve small pieces of metal such as razor blades or staples.
Medication errors are more common among seriously ill patients than with those with minor conditions.
Thyroid conditions cause a higher risk of fibromyalgia and chronic fatigue syndrome.
Blood is approximately twice as thick as water because of the cells and other components found in it.
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