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Did you know?

During pregnancy, a woman is more likely to experience bleeding gums and nosebleeds caused by hormonal changes that increase blood flow to the mouth and nose.

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There are approximately 3 million unintended pregnancies in the United States each year.

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About 3% of all pregnant women will give birth to twins, which is an increase in rate of nearly 60% since the early 1980s.

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Adult head lice are gray, about ? inch long, and often have a tiny dot on their backs. A female can lay between 50 and 150 eggs within the several weeks that she is alive. They feed on human blood.

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The highest suicide rate in the United States is among people ages 65 years and older. Almost 15% of people in this age group commit suicide every year.

A comparison of selected species of bacteria and archaea. A comparison of selected species of bacteria and archaea.
Scanning electron micrograph of a macrophage engulfing numerous bacteria. Scanning electron micrograph of a macrophage engulfing numerous bacteria.
E. coli bacteria cell E. coli bacteria cell
Many human diseases are caused by mutations in single genes Many human diseases are caused by mutations in single genes
Gram-stained bacteria on a microscope slide. (A) Red rod-shaped cells are Escherichia coli (Courtesy ... Gram-stained bacteria on a microscope slide. (A) Red rod-shaped cells are Escherichia coli (Courtesy ...
Cold front Cold front
Video: Tuberculosis Testing

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