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The longest a person has survived after a heart transplant is 24 years.
In the United States, there is a birth every 8 seconds, according to the U.S. Census Bureau's Population Clock.
Everyone has one nostril that is larger than the other.
Most childhood vaccines are 90–99% effective in preventing disease. Side effects are rarely serious.
Multiple sclerosis is a condition wherein the body's nervous system is weakened by an autoimmune reaction that attacks the myelin sheaths of neurons.
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