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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There are more sensory neurons in the tongue than in any other part of the body.

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Critical care patients are twice as likely to receive the wrong medication. Of these errors, 20% are life-threatening, and 42% require additional life-sustaining treatments.

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In 1864, the first barbiturate (barbituric acid) was synthesized.

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The human body produces and destroys 15 million blood cells every second.

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