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The immune system needs 9.5 hours of sleep in total darkness to recharge completely.

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Drugs are in development that may cure asthma and hay fever once and for all. They target leukotrienes, which are known to cause tightening of the air passages in the lungs and increase mucus productions in nasal passages.

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Once thought to have neurofibromatosis, Joseph Merrick (also known as "the elephant man") is now, in retrospect, thought by clinical experts to have had Proteus syndrome. This endocrine disease causes continued and abnormal growth of the bones, muscles, skin, and so on and can become completely debilitating with severe deformities occurring anywhere on the body.

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In 1844, Charles Goodyear obtained the first patent for a rubber condom.

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The shortest mature adult human of whom there is independent evidence was Gul Mohammed in India. In 1990, he was measured in New Delhi and stood 22.5 inches tall.

Preschoolers benefit from helping with meal preparation, especially with foods they like Preschoolers benefit from helping with meal preparation, especially with foods they like
The recent mass upheavals in Tunisia, Egypt, Libya, Yemen, and Syria gave political scientists a cha The recent mass upheavals in Tunisia, Egypt, Libya, Yemen, and Syria gave political scientists a cha
In the summer of 1793, a yellow fever epidemic struck Philadelphia, killing nearly 4,000. Tens of th In the summer of 1793, a yellow fever epidemic struck Philadelphia, killing nearly 4,000. Tens of th
American Foreign Trade, 1790–1812 American Foreign Trade, 1790–1812
Percentage of Foreign-Born Whites and Native Whites of Foreign or Mixed Parentage in Total Populatio Percentage of Foreign-Born Whites and Native Whites of Foreign or Mixed Parentage in Total Populatio
Growth of Government Spending, 1870–2009 Growth of Government Spending, 1870–2009
Video: Muscular System Animation

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