问题 单项选择题 A型题

该病例心脏超声检查如图(彩图16)所示,最可能的诊断为()。

A.原发孔房间隔缺损

B.继发孔房间隔缺损

C.冠状静脉窦隔缺损

D.部分型肺静脉畸形引流

E.部分型心内膜垫缺损

答案

参考答案:A

单项选择题 A型题
阅读理解

Reading comprehension.

     The 2012 London Olympics had enough problems to worry about. But one more has just been added-a

communications blackout caused by solar storms.

     After a period of calm within the Sun, scientists have detected the signs of a flesh cycle of sunspots that

could peak in 2012, just in time for the arrival of the Olympic torch in London.

     Now scientists believe that this peak could result in vast solar explosions that could throw billions of tons

of charged matter towards the Earth, causing strong solar storms that could jam the telecommunications

satellites and interact links sending five Olympic broadcast from London.

     "The Sun's activity has a strong influence on the Earth. The Olympics could be in the middle of the next

solar maximum which could affect the functions of communications satellites," said Professor Richard

Harrison, head of space physics at the Rutherford Appleton Laboratory in Oxfordshire.

     At the peak of the cycle, violent outbursts called coronal mass ejections (日冕物质抛射) occur in the

Sun's atmosphere, throwing out great quantities of electrically-charged matter. "A coronal mass ejection can

carry a billion tons of solar material into space at over a million kilometres per hour. Such events can expose

astronauts to a deadly amount, can disable satellites, cause power failures on Earth and disturb

communications," Professor Harrison added. The risk is greatest during a solar maximum when there is the

greatest number of sunspots.

     Next week in America, NASA is scheduled to launch a satellite for monitoring solar activity called the

Solar Dynamics Observatory (SDO), which will take images of the Sun that are 10 times clearer than the

most advanced televisions available.

     The Rutherford Appleton Laboratory helped to make the high-tech cameras that will capture images of

the solar flares (太阳耀斑) and explosions as they occur.

     Professor Richard Hold away, the lab's director, said that the SDO should be able to provide early warning

of a solar flare or explosion big enough to affect satellite communications on Earth "If we have advance

warning, we'll be able to reduce the damage. What you don't want is things switching off for a week with no

idea of what's caused the problem," he said.

1. The phrase "communications blackout" in paragraph 1 most probably refers to _____ during the 2012

    Olympics. [ ]

A. the extinguishing of the Olympic torch

B. the collapse of broadcasting systems

C. the transportation breakdown in London

D. the destruction of weather satellites

2. What can be inferred about the solar activity described in the passage? [ ]

A. The most fatal matter from the corona falls onto Earth.

B. The solar storm peak occurs in the middle of each cycle.

C. It takes several seconds for the charged matter to reach Earth.

D. The number of sunspots declines after coronal mass ejections.

3. According to the passage, NASA will launch a satellite to _____. [ ]

A. take images of the solar system

B. provide early warning of thunderstorms

C. keep track of solar activities

D. improve the communications on Earth

4. Which of the following might be the best title of the passage? [ ]

A. Solar Storms: An Invisible Killer

B. Solar Storms: Earth Environment in Danger

C. Solar Storms: Threatening the Human Race

D. Solar Storms: Human Activities to Be Troubled