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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 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.
Fungal nail infections account for up to 30% of all skin infections. They affect 5% of the general population—mostly people over the age of 70.
There are more sensory neurons in the tongue than in any other part of the body.
There are approximately 3 million unintended pregnancies in the United States each year.
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