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Author Question: After water vapor, ________ is the most plentiful of the variable gases in the atmosphere. A) ... (Read 46 times) |
More than 50% of American adults have oral herpes, which is commonly known as "cold sores" or "fever blisters." The herpes virus can be active on the skin surface without showing any signs or causing any symptoms.
More than 2,500 barbiturates have been synthesized. At the height of their popularity, about 50 were marketed for human use.
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.
Most childhood vaccines are 90–99% effective in preventing disease. Side effects are rarely serious.
No drugs are available to relieve parathyroid disease. Parathyroid disease is caused by a parathyroid tumor, and it needs to be removed by surgery.