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If all the neurons in the human body were lined up, they would stretch more than 600 miles.
Bacteria have flourished on the earth for over three billion years. They were the first life forms on the planet.
Most women experience menopause in their 50s. However, in 1994, an Italian woman gave birth to a baby boy when she was 61 years old.
About 100 new prescription or over-the-counter drugs come into the U.S. market every year.
Vaccines prevent between 2.5 and 4 million deaths every year.
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