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Did you know?

A cataract is a clouding of the eyes' natural lens. As we age, some clouding of the lens may occur. The first sign of a cataract is usually blurry vision. Although glasses and other visual aids may at first help a person with cataracts, surgery may become inevitable. Cataract surgery is very successful in restoring vision, and it is the most frequently performed surgery in the United States.

Did you know?

Pope Sylvester II tried to introduce Arabic numbers into Europe between the years 999 and 1003, but their use did not catch on for a few more centuries, and Roman numerals continued to be the primary number system.

Did you know?

If you could remove all of your skin, it would weigh up to 5 pounds.

Did you know?

A strange skin disease referred to as Morgellons has occurred in the southern United States and in California. Symptoms include slowly healing sores, joint pain, persistent fatigue, and a sensation of things crawling through the skin. Another symptom is strange-looking, threadlike extrusions coming out of the skin.

Did you know?

Vaccines cause herd immunity. If the majority of people in a community have been vaccinated against a disease, an unvaccinated person is less likely to get the disease since others are less likely to become sick from it and spread the disease.

Catbirds and robins reject objects shaped similarly to cowbird eggs no more frequently than objects Catbirds and robins reject objects shaped similarly to cowbird eggs no more frequently than objects
Rule of Nines. A method for determining percentage of body burned. Each different colored section re Rule of Nines. A method for determining percentage of body burned. Each different colored section re
9-18 Kuiper Belt Objects 9-18 Kuiper Belt Objects
Pure Word Deafness Pure Word Deafness
Phonological and Whole-Word Reading Phonological and Whole-Word Reading
a solution is prepared in which a trace or small amount of Fe2+ is added to a much larger ... a solution is prepared in which a trace or small amount of Fe2+ is added to a much larger ...
Video: Sperm Formation

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