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Normal urine is sterile. It contains fluids, salts, and waste products. It is free of bacteria, viruses, and fungi.
No drugs are available to relieve parathyroid disease. Parathyroid disease is caused by a parathyroid tumor, and it needs to be removed by surgery.
There are more nerve cells in one human brain than there are stars in the Milky Way.
The familiar sounds of your heart are made by the heart's valves as they open and close.
Approximately 500,000 babies are born each year in the United States to teenage mothers.
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