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Vaccines cause herd immunity. If the majority of people in a community have been vaccinated against a disease, an unvaccinated person is less likely to get the disease since others are less likely to become sick from it and spread the disease.
Most strokes are caused when blood clots move to a blood vessel in the brain and block blood flow to that area. Thrombolytic therapy can be used to dissolve the clot quickly. If given within 3 hours of the first stroke symptoms, this therapy can help limit stroke damage and disability.
After a vasectomy, it takes about 12 ejaculations to clear out sperm that were already beyond the blocked area.
Urine turns bright yellow if larger than normal amounts of certain substances are consumed; one of these substances is asparagus.
The average office desk has 400 times more bacteria on it than a toilet.
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