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.
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There can actually be a 25-hour time difference between certain locations in the world. The International Date Line passes between the islands of Samoa and American Samoa. It is not a straight line, but "zig-zags" around various island chains. Therefore, Samoa and nearby islands have one date, while American Samoa and nearby islands are one day behind. Daylight saving time is used in some islands, but not in others—further shifting the hours out of sync with natural time.
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Multiple sclerosis is a condition wherein the body's nervous system is weakened by an autoimmune reaction that attacks the myelin sheaths of neurons.
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According to the CDC, approximately 31.7% of the U.S. population has high low-density lipoprotein (LDL) or "bad cholesterol" levels.
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Drug-induced pharmacodynamic effects manifested in older adults include drug-induced renal toxicity, which can be a major factor when these adults are experiencing other kidney problems.
Human Skin
Human Eye Diagram
The skull of Sahelanthropus tchadensis is argued to be the earliest of the hominins and one of only
Organization of the Food and Drug Administration showing the seven centers that regulate human and ...
The motor homunculus: the somatotopic map of the human primary motor cortex. Stimulation of sites in ...
Apoptosis in the formation of a human hand