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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Cytomegalovirus affects nearly the same amount of newborns every year as Down syndrome.
Did you know?
For high blood pressure (hypertension), a new class of drug, called a vasopeptidase blocker (inhibitor), has been developed. It decreases blood pressure by simultaneously dilating the peripheral arteries and increasing the body's loss of salt.
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The human body's pharmacokinetics are quite varied. Our hair holds onto drugs longer than our urine, blood, or saliva. For example, alcohol can be detected in the hair for up to 90 days after it was consumed. The same is true for marijuana, cocaine, ecstasy, heroin, methamphetamine, and nicotine.
Did you know?
Blood is approximately twice as thick as water because of the cells and other components found in it.
Hand Washing Using Soap and Water
Smallest Fish in the world
Shallow-water systems are highly productive
Penicillin saved the lives of many soldiers in World War II
