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Author Question: P waves usually appear before: A) upright waves. B) QRS complexes. C) PR intervals. D) T ... (Read 31 times) |
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This year, an estimated 1.4 million Americans will have a new or recurrent heart attack.
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Autoimmune diseases occur when the immune system destroys its own healthy tissues. When this occurs, white blood cells cannot distinguish between pathogens and normal cells.
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Asthma occurs in one in 11 children and in one in 12 adults. African Americans and Latinos have a higher risk for developing asthma than other groups.
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About 100 new prescription or over-the-counter drugs come into the U.S. market every year.
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Approximately 500,000 babies are born each year in the United States to teenage mothers.