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Thyroid conditions cause a higher risk of fibromyalgia and chronic fatigue syndrome.
The familiar sounds of your heart are made by the heart's valves as they open and close.
There are approximately 3 million unintended pregnancies in the United States each year.
The ratio of hydrogen atoms to oxygen in water (H2O) is 2:1.
There are more nerve cells in one human brain than there are stars in the Milky Way.
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