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Multiple sclerosis is a condition wherein the body's nervous system is weakened by an autoimmune reaction that attacks the myelin sheaths of neurons.
Blood in the urine can be a sign of a kidney stone, glomerulonephritis, or other kidney problems.
Sperm cells are so tiny that 400 to 500 million (400,000,000–500,000,000) of them fit onto 1 tsp.
More than 34,000 trademarked medication names and more than 10,000 generic medication names are in use in the United States.
Blood is approximately twice as thick as water because of the cells and other components found in it.
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