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If you could remove all of your skin, it would weigh up to 5 pounds.
Cytomegalovirus affects nearly the same amount of newborns every year as Down syndrome.
Multiple sclerosis is a condition wherein the body's nervous system is weakened by an autoimmune reaction that attacks the myelin sheaths of neurons.
Today, nearly 8 out of 10 pregnant women living with HIV (about 1.1 million), receive antiretrovirals.
The immune system needs 9.5 hours of sleep in total darkness to recharge completely.
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