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Did you know?

Hippocrates noted that blood separates into four differently colored liquids when removed from the body and examined: a pure red liquid mixed with white liquid material with a yellow-colored froth at the top and a black substance that settles underneath; he named these the four humors (for blood, phlegm, yellow bile, and black bile).

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Vaccines prevent between 2.5 and 4 million deaths every year.

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Amphetamine poisoning can cause intravascular coagulation, circulatory collapse, rhabdomyolysis, ischemic colitis, acute psychosis, hyperthermia, respiratory distress syndrome, and pericarditis.

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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.

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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.

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Video: Evolutionary tree of life Animation

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