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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.
In the United States, an estimated 50 million unnecessary antibiotics are prescribed for viral respiratory infections.
More than nineteen million Americans carry the factor V gene that causes blood clots, pulmonary embolism, and heart disease.
Approximately 25% of all reported medication errors result from some kind of name confusion.
Vampire bats have a natural anticoagulant in their saliva that permits continuous bleeding after they painlessly open a wound with their incisors. This capillary blood does not cause any significant blood loss to their victims.