|
|
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.
Many medications that are used to treat infertility are injected subcutaneously. This is easy to do using the anterior abdomen as the site of injection but avoiding the area directly around the belly button.
The immune system needs 9.5 hours of sleep in total darkness to recharge completely.
Elderly adults are at greatest risk of stroke and myocardial infarction and have the most to gain from prophylaxis. Patients ages 60 to 80 years with blood pressures above 160/90 mm Hg should benefit from antihypertensive treatment.
Patients who cannot swallow may receive nutrition via a parenteral route—usually, a catheter is inserted through the chest into a large vein going into the heart.