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The Babylonians wrote numbers in a system that used 60 as the base value rather than the number 10. They did not have a symbol for "zero."

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A serious new warning has been established for pregnant women against taking ACE inhibitors during pregnancy. In the study, the risk of major birth defects in children whose mothers took ACE inhibitors during the first trimester was nearly three times higher than in children whose mothers didn't take ACE inhibitors. Physicians can prescribe alternative medications for pregnant women who have symptoms of high blood pressure.

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Multiple experimental evidences have confirmed that at the molecular level, cancer is caused by lesions in cellular DNA.

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If you could remove all of your skin, it would weigh up to 5 pounds.

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Calcitonin is a naturally occurring hormone. In women who are at least 5 years beyond menopause, it slows bone loss and increases spinal bone density.

Skeleton of Walrus Skeleton of Walrus
Anterior view of the human skeleton. Anterior view of the human skeleton.
Bones of the spinal column. Bones of the spinal column.
(a) The site of Zhoukoudian outside of Beijing, China, spans several hundred thousand years and (b) (a) The site of Zhoukoudian outside of Beijing, China, spans several hundred thousand years and (b)
Bones of the Human Skull Bones of the Human Skull
Real skeleton of a lion Real skeleton of a lion
Video: Introduction to Spirometry

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