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Author Question: During the first three decades of the 20th century, biologists viewed Mendelian genetics as a ... (Read 65 times) |
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.
Blood in the urine can be a sign of a kidney stone, glomerulonephritis, or other kidney problems.
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.
On average, someone in the United States has a stroke about every 40 seconds. This is about 795,000 people per year.
In the United States, there is a birth every 8 seconds, according to the U.S. Census Bureau's Population Clock.