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Bacteria have flourished on the earth for over three billion years. They were the first life forms on the planet.
Everyone has one nostril that is larger than the other.
In 1864, the first barbiturate (barbituric acid) was synthesized.
Blood in the urine can be a sign of a kidney stone, glomerulonephritis, or other kidney problems.
Malaria was not eliminated in the United States until 1951. The term eliminated means that no new cases arise in a country for 3 years.
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