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The upper chuck holds the upper end of the blade; the lower chuck holds the other end. The lowerchuck is driven by a crank mechanism in the base.
In the United States, there is a birth every 8 seconds, according to the U.S. Census Bureau's Population Clock.
There are approximately 3 million unintended pregnancies in the United States each year.
Calcitonin is a naturally occurring hormone. In women who are at least 5 years beyond menopause, it slows bone loss and increases spinal bone density.
In 2012, nearly 24 milliion Americans, aged 12 and older, had abused an illicit drug, according to the National Institute on Drug Abuse (NIDA).
Aspirin is the most widely used drug in the world. It has even been recognized as such by the Guinness Book of World Records.
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