|
|
Dogs have been used in studies to detect various cancers in human subjects. They have been trained to sniff breath samples from humans that were collected by having them breathe into special tubes. These people included 55 lung cancer patients, 31 breast cancer patients, and 83 cancer-free patients. The dogs detected 54 of the 55 lung cancer patients as having cancer, detected 28 of the 31 breast cancer patients, and gave only three false-positive results (detecting cancer in people who didn't have it).
Blood is approximately twice as thick as water because of the cells and other components found in it.
In the United States, an estimated 50 million unnecessary antibiotics are prescribed for viral respiratory infections.
More than 2,500 barbiturates have been synthesized. At the height of their popularity, about 50 were marketed for human use.
The modern decimal position system was the invention of the Hindus (around 800 AD), involving the placing of numerals to indicate their value (units, tens, hundreds, and so on).