问题 单项选择题

女,33岁,常感觉活动后胸闷、气短。查体:双颧绀红,心尖部第一心音亢进,心尖部有舒张期雷鸣样杂音,肺动脉瓣区第二心音亢进。

患者心电图P波的特点是

A.P波高而尖

B.V1导P波呈双相

C.P-R间期>0.20s

D.无P波

答案

参考答案:B

解析:[考点] 二尖瓣狭窄的诊断
患者在活动后有胸闷、气短症状,检查发现双颧绀红,S1亢进,舒张期雷鸣样杂音,P2亢进,这些均符合二类瓣狭窄的表现和体征。为明确和量化诊断,可靠的方法是超声心动图,在M型能显示二尖瓣前叶有城墙样改变,后叶向前移动及瓣叶增厚。
二尖瓣狭窄者心电图中以P波变化为特点,在Ⅰ、Ⅱ、aVL、aVR导联,P波增宽,呈双峰型(称为二尖瓣型P波);在V1导联,P波呈先正后负的双相波。二尖瓣狭窄导致左心房扩大,心电图中不会无P波。但是P波不显现高尖特点,P波高而尖是右房肥大的心电图特点。P-R间期不会增大,因为不会产生房室传导障碍。

单项选择题

Most people would be (1) by the high quality of medicine (2) to most Americans. There is a lot of specialization, a great deal of (3) to the individual, a (4) amount of advanced technical equipment, and (5) effort not to make mistakes because of the financial risk which doctors and hospitals must (6) in the courts if they (7) things badly.

But the Americans are in a mess. The problem is the way in (8) health care is organized and (9) . (10) to pubic belief it is not just a free competition system. The private system has been joined a large public system, because private care was simply not (11) the less fortunate and the elderly.

But even with this huge public part of the system, (12) this year will eat up 84.5 billion dollars—more than 10 percent of the U. S. Budget—large number of Americans are left (13) . These include about half the 11 million unemployed and those who fail to meet the strict limits (14) income fixed by a government trying to make savings where it can.

The basic problem, however, is that there is no central control (15) the health system. There is no (16) to what doctors and hospitals charge for their services, other than what the public is able to pay. The number of doctors has shot up and prices have climbed. When faced with toothache, a sick child, or a heart attack, all the unfortunate persons concerned can do is (17) up. Two thirds of the population (18) covered by medical insurance. Doctors charge as much as they want (19) that the insurance company will pay the bill.

The rising cost of medicine in the U. S. A. is among the most worrying problems facing the country. In 1981 the country’s health bill climbed 15.9 percent--about twice as fast as prices (20) general.

6()

A. run into

B. encounter

C. face

D. defy

单项选择题