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Author Question: A solution is 40.0% by mass benzene (C6H6) in carbon tetrachloride (CCl4) at 20C. The vapor pressure ... (Read 3432 times) |
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.
In Eastern Europe and Russia, interferon is administered intranasally in varied doses for the common cold and influenza. It is claimed that this treatment can lower the risk of infection by as much as 60–70%.
Astigmatism is the most common vision problem. It may accompany nearsightedness or farsightedness. It is usually caused by an irregularly shaped cornea, but sometimes it is the result of an irregularly shaped lens. Either type can be corrected by eyeglasses, contact lenses, or refractive surgery.
Illicit drug use costs the United States approximately $181 billion every year.
Asthma is the most common chronic childhood disease in the world. Most children who develop asthma have symptoms before they are 5 years old.