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If all the neurons in the human body were lined up, they would stretch more than 600 miles.
Cancer has been around as long as humankind, but only in the second half of the twentieth century did the number of cancer cases explode.
The first oncogene was discovered in 1970 and was termed SRC (pronounced "SARK").
Normal urine is sterile. It contains fluids, salts, and waste products. It is free of bacteria, viruses, and fungi.
Vaccines prevent between 2.5 and 4 million deaths every year.
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