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When blood is exposed to air, it clots. Heparin allows the blood to come in direct contact with air without clotting.
Between 1999 and 2012, American adults with high total cholesterol decreased from 18.3% to 12.9%
It is difficult to obtain enough calcium without consuming milk or other dairy foods.
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.
A cataract is a clouding of the eyes' natural lens. As we age, some clouding of the lens may occur. The first sign of a cataract is usually blurry vision. Although glasses and other visual aids may at first help a person with cataracts, surgery may become inevitable. Cataract surgery is very successful in restoring vision, and it is the most frequently performed surgery in the United States.