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Cytomegalovirus affects nearly the same amount of newborns every year as Down syndrome.
The familiar sounds of your heart are made by the heart's valves as they open and close.
In 1864, the first barbiturate (barbituric acid) was synthesized.
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.
Normal urine is sterile. It contains fluids, salts, and waste products. It is free of bacteria, viruses, and fungi.
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