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The horizontal fraction bar was introduced by the Arabs.
Multiple sclerosis is a condition wherein the body's nervous system is weakened by an autoimmune reaction that attacks the myelin sheaths of neurons.
Fungal nail infections account for up to 30% of all skin infections. They affect 5% of the general population—mostly people over the age of 70.
Bacteria have been found alive in a lake buried one half mile under ice in Antarctica.
In the United States, an estimated 50 million unnecessary antibiotics are prescribed for viral respiratory infections.
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