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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.
Human stomach acid is strong enough to dissolve small pieces of metal such as razor blades or staples.
Bacteria have flourished on the earth for over three billion years. They were the first life forms on the planet.
More than nineteen million Americans carry the factor V gene that causes blood clots, pulmonary embolism, and heart disease.
The immune system needs 9.5 hours of sleep in total darkness to recharge completely.
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