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Only one in 10 cancer deaths is caused by the primary tumor. The vast majority of cancer mortality is caused by cells breaking away from the main tumor and metastasizing to other parts of the body, such as the brain, bones, or liver.
Many of the drugs used by neuroscientists are derived from toxic plants and venomous animals (such as snakes, spiders, snails, and puffer fish).
HIV testing reach is still limited. An estimated 40% of people with HIV (more than 14 million) remain undiagnosed and do not know their infection status.
More than 150,000 Americans killed by cardiovascular disease are younger than the age of 65 years.
In 2012, nearly 24 milliion Americans, aged 12 and older, had abused an illicit drug, according to the National Institute on Drug Abuse (NIDA).
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