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Did you know?

Pope Sylvester II tried to introduce Arabic numbers into Europe between the years 999 and 1003, but their use did not catch on for a few more centuries, and Roman numerals continued to be the primary number system.

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About 100 new prescription or over-the-counter drugs come into the U.S. market every year.

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Before a vaccine is licensed in the USA, the Food and Drug Administration (FDA) reviews it for safety and effectiveness. The CDC then reviews all studies again, as well as the American Academy of Pediatrics and the American Academy of Family Physicians. Every lot of vaccine is tested before administration to the public, and the FDA regularly inspects vaccine manufacturers' facilities.

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ACTH levels are normally highest in the early morning (between 6 and 8 A.M.) and lowest in the evening (between 6 and 11 P.M.). Therefore, a doctor who suspects abnormal levels looks for low ACTH in the morning and high ACTH in the evening.

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Side effects from substance abuse include nausea, dehydration, reduced productivitiy, and dependence. Though these effects usually worsen over time, the constant need for the substance often overcomes rational thinking.

HEART HEART
Wood first appeared in plants called progymnosperms. Wood first appeared in plants called progymnosperms.
Color enhanced X-ray showing a pacemaker implanted in the left side of the chest and the electrode w Color enhanced X-ray showing a pacemaker implanted in the left side of the chest and the electrode w
Heart Flow Heart Flow
Children with disabilities used to be sent to special schools. In a process called mainstreaming or ... Children with disabilities used to be sent to special schools. In a process called mainstreaming or ...
A commercially available DNA microarray, called a GeneChip, marketed by Affymetrix, Inc A commercially available DNA microarray, called a GeneChip, marketed by Affymetrix, Inc
Video: Cellular defenses (natural killer cells, phagocyte types & process of phagocytosis)

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