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Did you know?
Astigmatism is the most common vision problem. It may accompany nearsightedness or farsightedness. It is usually caused by an irregularly shaped cornea, but sometimes it is the result of an irregularly shaped lens. Either type can be corrected by eyeglasses, contact lenses, or refractive surgery.
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Not getting enough sleep can greatly weaken the immune system. Lack of sleep makes you more likely to catch a cold, or more difficult to fight off an infection.
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The first oncogene was discovered in 1970 and was termed SRC (pronounced "SARK").
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Between 1999 and 2012, American adults with high total cholesterol decreased from 18.3% to 12.9%
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Bacteria have flourished on the earth for over three billion years. They were the first life forms on the planet.

