问题 单项选择题

梗塞后心绞痛患者容易发生()

A.梗塞延展

B.心绞痛

C.室壁瘤

D.栓塞

E.再梗死

答案

参考答案:A

阅读理解

阅读理解。

     With only about 1, 000 pandas left in the world, China is desperately trying to clone (克隆) the animal

and save the endangered species(物种). That's a move similar to what a Texas A & M University

researchers have been undertaking for the past five years in a project called "Noah's Ark".

     Noah's Ark is aimed at collecting eggs, embryos(胚胎), semen and DNA of endangered animals and

storing them in liquid nitrogen. If certain species should become extinct, Dr. Duane Kraemer, a professor

in Texas A & M's College of Veterinary Medicine, says there would be enough of the basic building

blocks to reintroduce the species in the future.

     It is estimated that as many as 2, 000 species of mammals, birds reptiles will become extinct in over

100 years. The panda, native only to China, is in danger of becoming extinct in the next 25 years.

     This week, Chinese scientists said they grew an embryo by introducing cells from a dead female panda

into the egg cells of a Japanese white rabbit. They are now trying to implant the embryo into a host animal.

The entire procedure could take from three to five years to complete.

     "The nuclear transfer(核子移植) of one species to another is not easy, and the lack of available

panda eggs could be a major problem," Kraemer believes. "They will probably have to do several

hundred transfers to result in one pregnancy (having a baby). It takes a long time and it's difficult, but this

could be groundbreaking science if it works. They are certainly not putting any live pandas at risk, so it

is worth the effort," adds Kraemer, who is one of the leaders of the Project at Texas A & M, the

first-ever attempt at cloning a dog.

     "They are trying to do something that's never been done, and this is very similar to our work in

Noah's Ark. We're both trying to save animals that face extinction. I certainly appreciate their effort and

there's a lot we can learn from what they are attempting to do. It's a research that is very much needed."

1. The aim of "Noah's Ark" project is to _______.

A. make efforts to clone the endangered pandas

B. save endangered animals from dying out

C. collect DNA of endangered animals to study

D. transfer the nuclear of one animal to another

2. According to Professor Kraemer, the major problem in cloning pandas would be the lack of _______.

A. available panda eggs        

B. host animals

C. qualified researchers    

D. enough money

3. Which of the following should be the best title for the passage?

A. China's Success in Pandas Cloning  

B. The First Cloned Panda in the World

C. Exploring the Possibility to Clone Pandas

D. China -the Native Place of Pandas Forever

4. From the passage we know that _______.

A. Kraemer and his team have succeeded in cloning a dog

B. scientists try to implant a panda's egg into a rabbit

C. Kraemer will work with Chinese scientists in clone researches

D. about two thousand of species will probably die out in a century

单项选择题