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Author Question: A string of twelve holiday lamps is designed to be connected in series to a 120-V source. If one of ... (Read 3758 times) |
The first-known contraceptive was crocodile dung, used in Egypt in 2000 BC. Condoms were also reportedly used, made of animal bladders or intestines.
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.
For about 100 years, scientists thought that peptic ulcers were caused by stress, spicy food, and alcohol. Later, researchers added stomach acid to the list of causes and began treating ulcers with antacids. Now it is known that peptic ulcers are predominantly caused by Helicobacter pylori, a spiral-shaped bacterium that normally exist in the stomach.
Critical care patients are twice as likely to receive the wrong medication. Of these errors, 20% are life-threatening, and 42% require additional life-sustaining treatments.
In 1864, the first barbiturate (barbituric acid) was synthesized.