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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.
About 100 new prescription or over-the-counter drugs come into the U.S. market every year.
The calories found in one piece of cherry cheesecake could light a 60-watt light bulb for 1.5 hours.
Blood is approximately twice as thick as water because of the cells and other components found in it.
Autoimmune diseases occur when the immune system destroys its own healthy tissues. When this occurs, white blood cells cannot distinguish between pathogens and normal cells.

