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Author Question: __________ had the fewest opportunities for social inequality to emerge. a. Feudal societies b. ... (Read 22 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.
The longest a person has survived after a heart transplant is 24 years.
When blood is exposed to air, it clots. Heparin allows the blood to come in direct contact with air without clotting.
Multiple sclerosis is a condition wherein the body's nervous system is weakened by an autoimmune reaction that attacks the myelin sheaths of neurons.
Autoimmune diseases occur when the immune system destroys its own healthy tissues. When this occurs, white blood cells cannot distinguish between pathogens and normal cells.