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Author Question: A large spring is used to stop the cars after they come down the last hill of a roller coaster. The ... (Read 5661 times) |
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.
In 1886, William Bates reported on the discovery of a substance produced by the adrenal gland that turned out to be epinephrine (adrenaline). In 1904, this drug was first artificially synthesized by Friedrich Stolz.
Sperm cells are so tiny that 400 to 500 million (400,000,000–500,000,000) of them fit onto 1 tsp.
Historic treatments for rheumatoid arthritis have included gold salts, acupuncture, a diet consisting of apples or rhubarb, nutmeg, nettles, bee venom, bracelets made of copper, prayer, rest, tooth extractions, fasting, honey, vitamins, insulin, snow collected on Christmas, magnets, and electric convulsion therapy.
Since 1988, the CDC has reported a 99% reduction in bacterial meningitis caused by Haemophilus influenzae, due to the introduction of the vaccine against it.