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Most childhood vaccines are 90–99% effective in preventing disease. Side effects are rarely serious.
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.
After a vasectomy, it takes about 12 ejaculations to clear out sperm that were already beyond the blocked area.
The word drug comes from the Dutch word droog (meaning "dry"). For centuries, most drugs came from dried plants, hence the name.
Between 1999 and 2012, American adults with high total cholesterol decreased from 18.3% to 12.9%
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