|
Author Question: Energy is transferred by waves a) in the same direction as the propagation of the wave itself b) ... (Read 44 times) |
Acute bronchitis is an inflammation of the breathing tubes (bronchi), which causes increased mucus production and other changes. It is usually caused by bacteria or viruses, can be serious in people who have pulmonary or cardiac diseases, and can lead to pneumonia.
The average office desk has 400 times more bacteria on it than a toilet.
More than 2,500 barbiturates have been synthesized. At the height of their popularity, about 50 were marketed for human use.
Immunoglobulin injections may give short-term protection against, or reduce severity of certain diseases. They help people who have an inherited problem making their own antibodies, or those who are having certain types of cancer treatments.
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.