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Did you know?

According to the American College of Allergy, Asthma & Immunology, more than 50 million Americans have some kind of food allergy. Food allergies affect between 4 and 6% of children, and 4% of adults, according to the CDC. The most common food allergies include shellfish, peanuts, walnuts, fish, eggs, milk, and soy.

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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.

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Aspirin may benefit 11 different cancers, including those of the colon, pancreas, lungs, prostate, breasts, and leukemia.

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After a vasectomy, it takes about 12 ejaculations to clear out sperm that were already beyond the blocked area.

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Thyroid conditions may make getting pregnant impossible.

The extent of acid rain in the United States has decreased. The extent of acid rain in the United States has decreased.
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Video: Mechanisms for chromosome movement Animation

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