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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Bacteria have been found alive in a lake buried one half mile under ice in Antarctica.
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According to animal studies, the typical American diet is damaging to the liver and may result in allergies, low energy, digestive problems, and a lack of ability to detoxify harmful substances.
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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.
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Despite claims by manufacturers, the supplement known as Ginkgo biloba was shown in a study of more than 3,000 participants to be ineffective in reducing development of dementia and Alzheimer’s disease in older people.
Overview of blood flow through vessels in a closed circulatory system.
Emiliania huxleyi cells in an electro-microscopic picture.
