问题 单项选择题 A1/A2型题

女性,78岁。主动脉瓣关闭不全,该患者查体不存在的体征是()

A.胸骨左缘第2肋间连续性杂音

B.抬举样心尖搏动

C.水冲脉

D.枪击音

E.点头运动

答案

参考答案:A

解析:主动脉瓣关闭不全心脏听诊:主动脉瓣区舒张期杂音,为高调递减型叹气样杂音,坐位前倾呼气末时明显。最响区域取决于有无显著的升主动脉扩张;风湿性者主动脉扩张较轻,在胸骨左缘第3肋间最响,可沿胸骨缘下传至心尖区;马方综合征或梅毒性心脏病所致者,由于升主动脉或主动脉瓣环可有高度扩张,故杂音在胸骨右缘第2肋间最响。一般主动脉瓣关闭不全越严重,杂音所占的时间越长,响度越大。轻度关闭不全者,此杂音柔和,仅出现于舒张早期,只在患者取坐位前倾、呼气末才能听到;较重的关闭不全时,杂音可为全舒张期且粗糙;在重度或急性主动脉瓣关闭不全时,由于左心室舒张末期压力增高至与主动脉舒张压相等,故杂音持续时间反而缩短。如杂音带音乐性质,常提示瓣膜的一部分翻转、撕裂或穿孔。主动脉夹层分离有时也出现音乐性杂音,可能是由于舒张期近端主动脉内膜通过主动脉瓣向心室脱垂或中层主动脉管腔内血液流动之故。

阅读理解

阅读理解

     Easter(复活节) is still a great day for worship, randy in baskets and running around the yard finding

eggs, but every year it gets quite a bit worse for bunnies.

     And no, not because the kids like to pull their ears. The culprit is climate change, and some

researchers found that rising temperatures arc having harmful effects on at least five species of rabbit in

the US.

     Take the Lower Keys March rabbit, for instance. An endangered species that lives in the Lower

Florida Keys, this species of cottontail is a great swimmer - it lives on the islands! - but it is already

severely affected by development and now by rising levels. According to the Center for Biological

Diversity, an ocean level rise of only 0. 6 meters will send these guys jumping to higher ground and a

0.9-meter rise would wipe out their habitat (栖息地) completely.

     The snowshoe hare, on the other hand, has a color issue. Most of these rabbits change their fur color

from white in the wintertime to brown in the summer, each designed to give them better cover from

predators(捕食者).  As the number of days with snow decreases all across the country, however, more

and more bunnies arc being left in white fur during brown dirt days of both fall and spring, making them

an easier mark for predators. Researchers know that the color change is controlled by the number of

hours of sunlight, but whether the rabbit will be able to adapt quick enough to survive is a big question.

The National Wildlife   Federation has reported that hunters have noticed their numbers are already

markedly down.

     American pikas or rock rabbits, a relative of rabbits and hares, might be the firs' of these species to

go extinct due to climate change. About 7-8 inches long, pikas live high in the cool, damp mountains

west of the Rocky Mountains. As global temperatures rise, they would naturally migrate (迁徙) to higher

ground - but they already occupy the mountaintops. They can't go any higher. The National Wildlife

Federation reports that they might not be able to stand the new temperatures as their habitat beats up.

     The volcano rabbit has the same problem. These rabbits live on the slopes of volcanoes in Mexico,

and recent studies have shown that the lower range of their habitat has already shifted upward about

700 meters, but there are not suitable plants for them to move higher, so they are stuck in the middle.

Scientists are concerned about their populations.

     Native to the US, pygmy rabbits weigh less than 1 pound and live in the American West. They are

believed to be the smallest rabbits in the world. Their habitats have been destroyed by development.

Several populations, such as the Columbia Basin pygmy, almost went extinct and were saved by zoo

breeding programs. Pygmy rabbits also rely on winter cover by digging tunnels through the snow to

escape predators, but lesser snowfall is leaving them exposed.

      All of this gives new meaning to dressing up in a giant bunny costume this Easter.

1 The writer mentions Easter at the beginning of the passage in order to_______.

A. show the importance of Easter Day

B. introduce the issue about bunnies

C. remind people of Easter traditions  

D. discuss the relationship between Easter and bunnies

2. The word "culprit" ( Paragraph 2) is closest in meaning to______.

A. criminal

B. judge

C. victim

D. producer

3.According to the passage, some rabbits can now be easily Uncovered by predators because they___.

A. are exposed lo more skillful hunters

B. have moved to habitats with fewer plants

C. haven't adapted themselves to climate change

D. can't change their fur color into white in the fall and the spring

4. The problem faced by volcano rabbets and rock rabbits is that________.

A. both are affected by 1ess snow

B. both are affected by rising sea levels

C neither can find enough food 

D. neither can migrate to higher places

5 Which best describes the writer's tone in the postage?

A. Approving.

B. Concerned.

C. Enthusiastic.

D. Doubtful.

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