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Bacteria have flourished on the earth for over three billion years. They were the first life forms on the planet.
The first war in which wide-scale use of anesthetics occurred was the Civil War, and 80% of all wounds were in the extremities.
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.
Multiple experimental evidences have confirmed that at the molecular level, cancer is caused by lesions in cellular DNA.
Blood is approximately twice as thick as water because of the cells and other components found in it.
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