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Author Question: A person is nearsighted with a far point of 75.0 cm. (a) What focal length contact lens is needed ... (Read 56 times) |
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.
Multiple experimental evidences have confirmed that at the molecular level, cancer is caused by lesions in cellular DNA.
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.
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.
Stroke kills people from all ethnic backgrounds, but the people at highest risk for fatal strokes are: black men, black women, Asian men, white men, and white women.