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Blood is approximately twice as thick as water because of the cells and other components found in it.
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.
Your heart beats over 36 million times a year.
Multiple sclerosis is a condition wherein the body's nervous system is weakened by an autoimmune reaction that attacks the myelin sheaths of neurons.
There are approximately 3 million unintended pregnancies in the United States each year.
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