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Did you know?
Normal urine is sterile. It contains fluids, salts, and waste products. It is free of bacteria, viruses, and fungi.
Did you know?
Asthma cases in Americans are about 75% higher today than they were in 1980.
Did you know?
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.
Did you know?
Vaccines prevent between 2.5 and 4 million deaths every year.
Did you know?
There are 20 feet of blood vessels in each square inch of human skin.