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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.
Green tea is able to stop the scent of garlic or onion from causing bad breath.
Vaccines prevent between 2.5 and 4 million deaths every year.
After a vasectomy, it takes about 12 ejaculations to clear out sperm that were already beyond the blocked area.
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