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Bacteria have flourished on the earth for over three billion years. They were the first life forms on the planet.
Adult head lice are gray, about ? inch long, and often have a tiny dot on their backs. A female can lay between 50 and 150 eggs within the several weeks that she is alive. They feed on human blood.
Most strokes are caused when blood clots move to a blood vessel in the brain and block blood flow to that area. Thrombolytic therapy can be used to dissolve the clot quickly. If given within 3 hours of the first stroke symptoms, this therapy can help limit stroke damage and disability.
On average, the stomach produces 2 L of hydrochloric acid per day.
In the United States, an estimated 50 million unnecessary antibiotics are prescribed for viral respiratory infections.