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The U.S. Preventive Services Task Force recommends that all women age 65 years of age or older should be screened with bone densitometry.
About 600,000 particles of skin are shed every hour by each human. If you live to age 70 years, you have shed 105 pounds of dead skin.
About 3% of all pregnant women will give birth to twins, which is an increase in rate of nearly 60% since the early 1980s.
Bacteria have been found alive in a lake buried one half mile under ice in Antarctica.
In 1864, the first barbiturate (barbituric acid) was synthesized.
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