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The human body produces and destroys 15 million blood cells every second.
Asthma is the most common chronic childhood disease in the world. Most children who develop asthma have symptoms before they are 5 years old.
The first oncogene was discovered in 1970 and was termed SRC (pronounced "SARK").
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.
Approximately 500,000 babies are born each year in the United States to teenage mothers.
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