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Human kidneys will clean about 1 million gallons of blood in an average lifetime.
Asthma cases in Americans are about 75% higher today than they were in 1980.
If you could remove all of your skin, it would weigh up to 5 pounds.
The first oncogene was discovered in 1970 and was termed SRC (pronounced "SARK").
Vaccines prevent between 2.5 and 4 million deaths every year.
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