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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Cyanide works by making the human body unable to use oxygen.
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The U.S. Preventive Services Task Force recommends that all women age 65 years of age or older should be screened with bone densitometry.
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Colchicine is a highly poisonous alkaloid originally extracted from a type of saffron plant that is used mainly to treat gout.
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The most common treatment options for addiction include psychotherapy, support groups, and individual counseling.
Plant cell water potential.
A Human Cell
The cell wall of a Gram-negative bacterium, E. coli
Imaging cell surface glycoproteins in living cells