|
|
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.
After 5 years of being diagnosed with rheumatoid arthritis, one every three patients will no longer be able to work.
The first-known contraceptive was crocodile dung, used in Egypt in 2000 BC. Condoms were also reportedly used, made of animal bladders or intestines.
Opium has influenced much of the world's most popular literature. The following authors were all opium users, of varying degrees: Lewis Carroll, Charles, Dickens, Arthur Conan Doyle, and Oscar Wilde.
Vaccines prevent between 2.5 and 4 million deaths every year.