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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According to the FDA, adverse drug events harmed or killed approximately 1,200,000 people in the United States in the year 2015.
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The average human gut is home to perhaps 500 to 1,000 different species of bacteria.
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By definition, when a medication is administered intravenously, its bioavailability is 100%.
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In 2012, nearly 24 milliion Americans, aged 12 and older, had abused an illicit drug, according to the National Institute on Drug Abuse (NIDA).
