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There are over 65,000 known species of protozoa. About 10,000 species are parasitic.
More than 4.4billion prescriptions were dispensed within the United States in 2016.
There are more nerve cells in one human brain than there are stars in the Milky Way.
There are approximately 3 million unintended pregnancies in the United States each year.
Elderly adults are living longer, and causes of death are shifting. At the same time, autopsy rates are at or near their lowest in history.
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