The drug methacholine can stimulate parasympathetic receptors in the airways, causing bronchoconstriction. Epinephrine can stimulate ?2 receptors in the airways, causing bronchodilation
These two opposing effects that cancel each other out are an example of
a. chemical antagonism.
b. functional antagonism.
c. competitive antagonism.
d. synergism.
ANS: B
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Which of the following best describes the cardiovascular effects of calcium channel blockers, such as verapamil (Calan) and diltiazem (Cardizem)?
A) Increased peripheral vascular resistance, widened QRS, and increased afterload B) Increased heart rate and stroke volume, decreased afterload C) Decreased peripheral vascular resistance, widened QRS, and increased afterload D) Decreased automaticity and decreased AV node conductivity
Two of the immediate effects of the increase in malpractice litigation are seen in _____ malpractice insurance premiums and the _____ in the number of carriers willing to assume the risk
a. lower; decrease b. lower; increase c. higher; decrease d. higher; increase