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Did you know?

Urine turns bright yellow if larger than normal amounts of certain substances are consumed; one of these substances is asparagus.

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Although the Roman numeral for the number 4 has always been taught to have been "IV," according to historians, the ancient Romans probably used "IIII" most of the time. This is partially backed up by the fact that early grandfather clocks displayed IIII for the number 4 instead of IV. Early clockmakers apparently thought that the IIII balanced out the VIII (used for the number 8) on the clock face and that it just looked better.

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It is widely believed that giving a daily oral dose of aspirin to heart attack patients improves their chances of survival because the aspirin blocks the formation of new blood clots.

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Asthma cases in Americans are about 75% higher today than they were in 1980.

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Approximately 15–25% of recognized pregnancies end in miscarriage. However, many miscarriages often occur before a woman even knows she is pregnant.

The gill-withdrawal reflex in the sea slug. The gill-withdrawal reflex in the sea slug.
Large-scale impacts of the (a) positive, and (b) negative phases of the North Atlantic Oscillation. Large-scale impacts of the (a) positive, and (b) negative phases of the North Atlantic Oscillation.
Positive and Negative Symptoms of Schizophrenia Positive and Negative Symptoms of Schizophrenia
Negative feedback control of a regulated variable. Negative feedback control of a regulated variable.
Control of thyroxine secretion through negative feedback. Control of thyroxine secretion through negative feedback.
A Negative Afterimage A Negative Afterimage
Video: Premenstrual Syndrome

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