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Blood in the urine can be a sign of a kidney stone, glomerulonephritis, or other kidney problems.
There are 60,000 miles of blood vessels in every adult human.
Aspirin is the most widely used drug in the world. It has even been recognized as such by the Guinness Book of World Records.
The horizontal fraction bar was introduced by the Arabs.
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.
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