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Cancer has been around as long as humankind, but only in the second half of the twentieth century did the number of cancer cases explode.

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Pink eye is a term that refers to conjunctivitis, which is inflammation of the thin, clear membrane (conjunctiva) over the white part of the eye (sclera). It may be triggered by a virus, bacteria, or foreign body in the eye. Antibiotic eye drops alleviate bacterial conjunctivitis, and antihistamine allergy pills or eye drops help control allergic conjunctivitis symptoms.

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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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Hippocrates noted that blood separates into four differently colored liquids when removed from the body and examined: a pure red liquid mixed with white liquid material with a yellow-colored froth at the top and a black substance that settles underneath; he named these the four humors (for blood, phlegm, yellow bile, and black bile).

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Asthma-like symptoms were first recorded about 3,500 years ago in Egypt. The first manuscript specifically written about asthma was in the year 1190, describing a condition characterized by sudden breathlessness. The treatments listed in this manuscript include chicken soup, herbs, and sexual abstinence.

Stellar Birth Rates Stellar Birth Rates
U.S. Life Expectancy by Year of Birth U.S. Life Expectancy by Year of Birth
Country of Birth of Authorized U.S. Immigrants Country of Birth of Authorized U.S. Immigrants
Stages of Natural Birth "مراحل الولادة الطبيعية" Stages of Natural Birth "مراحل الولادة الطبيعية"
Birth Control Methods and Abortion Birth Control Methods and Abortion
Mirror recognition and self-naming develop at almost exactly the same time Mirror recognition and self-naming develop at almost exactly the same time
Video: Chemical Changes

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