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Did you know?

People who have myopia, or nearsightedness, are not able to see objects at a distance but only up close. It occurs when the cornea is either curved too steeply, the eye is too long, or both. This condition is progressive and worsens with time. More than 100 million people in the United States are nearsighted, but only 20% of those are born with the condition. Diet, eye exercise, drug therapy, and corrective lenses can all help manage nearsightedness.

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When Gabriel Fahrenheit invented the first mercury thermometer, he called "zero degrees" the lowest temperature he was able to attain with a mixture of ice and salt. For the upper point of his scale, he used 96°, which he measured as normal human body temperature (we know it to be 98.6° today because of more accurate thermometers).

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Multiple sclerosis is a condition wherein the body's nervous system is weakened by an autoimmune reaction that attacks the myelin sheaths of neurons.

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There are major differences in the metabolism of morphine and the illegal drug heroin. Morphine mostly produces its CNS effects through m-receptors, and at k- and d-receptors. Heroin has a slight affinity for opiate receptors. Most of its actions are due to metabolism to active metabolites (6-acetylmorphine, morphine, and morphine-6-glucuronide).

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Thyroid conditions may make getting pregnant impossible.

Key anatomical features of Homo habilis include reduced facial size, a parabolic palate, and some br Key anatomical features of Homo habilis include reduced facial size, a parabolic palate, and some br
The proboscis monkey demonstrates that large gut size contributes to a lower EQ. The proboscis monkey demonstrates that large gut size contributes to a lower EQ.
Bones change radically in size and shape from newborn to adult, as these cervical vertebrae demonstr Bones change radically in size and shape from newborn to adult, as these cervical vertebrae demonstr
The frontal sinus, an airfilled space just behind the brow, is a unique size and shape in each of us The frontal sinus, an airfilled space just behind the brow, is a unique size and shape in each of us
Europe’s Size and Location Europe’s Size and Location
Increase in total spending in presidential campaigns, 1976-2020 Increase in total spending in presidential campaigns, 1976-2020
Video: The Nerve Impulse

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