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There are over 65,000 known species of protozoa. About 10,000 species are parasitic.
Russia has the highest death rate from cardiovascular disease followed by the Ukraine, Romania, Hungary, and Poland.
More than 34,000 trademarked medication names and more than 10,000 generic medication names are in use in the United States.
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.
The Babylonians wrote numbers in a system that used 60 as the base value rather than the number 10. They did not have a symbol for "zero."