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The horizontal fraction bar was introduced by the Arabs.
In 1864, the first barbiturate (barbituric acid) was synthesized.
A cataract is a clouding of the eyes' natural lens. As we age, some clouding of the lens may occur. The first sign of a cataract is usually blurry vision. Although glasses and other visual aids may at first help a person with cataracts, surgery may become inevitable. Cataract surgery is very successful in restoring vision, and it is the most frequently performed surgery in the United States.
Asthma is the most common chronic childhood disease in the world. Most children who develop asthma have symptoms before they are 5 years old.
You should not take more than 1,000 mg of vitamin E per day. Doses above this amount increase the risk of bleeding problems that can lead to a stroke.