|
Author Question: Approximately what percentage of Americans will develop skin cancer in their lifetime? A) 5 B) 10 ... (Read 25 times) |
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.
More than 2,500 barbiturates have been synthesized. At the height of their popularity, about 50 were marketed for human use.
Chronic marijuana use can damage the white blood cells and reduce the immune system's ability to respond to disease by as much as 40%. Without a strong immune system, the body is vulnerable to all kinds of degenerative and infectious diseases.
Sildenafil (Viagra®) has two actions that may be of consequence in patients with heart disease. It can lower the blood pressure, and it can interact with nitrates. It should never be used in patients who are taking nitrates.
Most childhood vaccines are 90–99% effective in preventing disease. Side effects are rarely serious.