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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.
Excessive alcohol use costs the country approximately $235 billion every year.
Historic treatments for rheumatoid arthritis have included gold salts, acupuncture, a diet consisting of apples or rhubarb, nutmeg, nettles, bee venom, bracelets made of copper, prayer, rest, tooth extractions, fasting, honey, vitamins, insulin, snow collected on Christmas, magnets, and electric convulsion therapy.
Interferon was scarce and expensive until 1980, when the interferon gene was inserted into bacteria using recombinant DNA technology, allowing for mass cultivation and purification from bacterial cultures.
The first-known contraceptive was crocodile dung, used in Egypt in 2000 BC. Condoms were also reportedly used, made of animal bladders or intestines.