|
|
More than 2,500 barbiturates have been synthesized. At the height of their popularity, about 50 were marketed for human use.
Human stomach acid is strong enough to dissolve small pieces of metal such as razor blades or staples.
Nitroglycerin is used to alleviate various heart-related conditions, and it is also the chief component of dynamite (but mixed in a solid clay base to stabilize it).
It is believed that the Incas used anesthesia. Evidence supports the theory that shamans chewed cocoa leaves and drilled holes into the heads of patients (letting evil spirits escape), spitting into the wounds they made. The mixture of cocaine, saliva, and resin numbed the site enough to allow hours of drilling.
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).