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Did you know?

In the United States, there is a birth every 8 seconds, according to the U.S. Census Bureau's Population Clock.

Did you know?

About 100 new prescription or over-the-counter drugs come into the U.S. market every year.

Did you know?

There are over 65,000 known species of protozoa. About 10,000 species are parasitic.

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Congestive heart failure is a serious disorder that carries a reduced life expectancy. Heart failure is usually a chronic illness, and it may worsen with infection or other physical stressors.

Did you know?

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.

Hints of Earth’s Early Appearance Hints of Earth’s Early Appearance
Play in Four Cultures Across cultures, play is the most common activity in early childhood. Source: Play in Four Cultures Across cultures, play is the most common activity in early childhood. Source:
Raphael's mural, The School of Athens, depicts the early Greek philosophers engaged in ... Raphael's mural, The School of Athens, depicts the early Greek philosophers engaged in ...
Early cities were small economic centers surrounded by walls to keep out enemies. These cities had ... Early cities were small economic centers surrounded by walls to keep out enemies. These cities had ...
Early Warning Signs and Symptoms of Mental Disorders Early Warning Signs and Symptoms of Mental Disorders
Video: Endocytosis - pinocytosis, receptor mediated and Transcytosis

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