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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 most destructive flu epidemic of all times in recorded history occurred in 1918, with approximately 20 million deaths worldwide.
Certain topical medications such as clotrimazole and betamethasone are not approved for use in children younger than 12 years of age. They must be used very cautiously, as directed by a doctor, to treat any child. Children have a much greater response to topical steroid medications.
Alzheimer's disease affects only about 10% of people older than 65 years of age. Most forms of decreased mental function and dementia are caused by disuse (letting the mind get lazy).
The immune system needs 9.5 hours of sleep in total darkness to recharge completely.
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