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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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In 1864, the first barbiturate (barbituric acid) was synthesized.
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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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There are actually 60 minerals, 16 vitamins, 12 essential amino acids, and three essential fatty acids that your body needs every day.
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Asthma cases in Americans are about 75% higher today than they were in 1980.