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Vaccines prevent between 2.5 and 4 million deaths every year.
Aspirin is the most widely used drug in the world. It has even been recognized as such by the Guinness Book of World Records.
Today, nearly 8 out of 10 pregnant women living with HIV (about 1.1 million), receive antiretrovirals.
It is difficult to obtain enough calcium without consuming milk or other dairy foods.
The heart is located in the center of the chest, with part of it tipped slightly so that it taps against the left side of the chest.
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