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The average human gut is home to perhaps 500 to 1,000 different species of bacteria.
The first war in which wide-scale use of anesthetics occurred was the Civil War, and 80% of all wounds were in the extremities.
The Romans did not use numerals to indicate fractions but instead used words to indicate parts of a whole.
Asthma occurs in one in 11 children and in one in 12 adults. African Americans and Latinos have a higher risk for developing asthma than other groups.
Between 1999 and 2012, American adults with high total cholesterol decreased from 18.3% to 12.9%
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