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Blood is approximately twice as thick as water because of the cells and other components found in it.
There are more bacteria in your mouth than there are people in the world.
Pubic lice (crabs) are usually spread through sexual contact. You cannot catch them by using a public toilet.
The U.S. Preventive Services Task Force recommends that all women age 65 years of age or older should be screened with bone densitometry.
The heart is located in the center of the chest, with part of it tipped slightly so that it taps against the left side of the chest.
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