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The B-complex vitamins and vitamin C are not stored in the body and must be replaced each day.
The first documented use of surgical anesthesia in the United States was in Connecticut in 1844.
The horizontal fraction bar was introduced by the Arabs.
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.
There are over 65,000 known species of protozoa. About 10,000 species are parasitic.
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