问题 单项选择题

以下对头孢菌素类药物描述不正确的是()

A、第一代头孢菌素主要作用于需氧革兰阳性球菌,仅对少数革兰阴性杆菌有一定抗菌活性

B、第二代头孢菌素对革兰阳性球菌的活性与第一代相仿或略差,对部分革兰阴性杆菌亦具有抗菌活性

C、第三代头孢菌素对肠杆菌科细菌等革兰阴性杆菌具有强大抗菌作用

D、第四代头孢菌素对金葡菌等革兰阳性球菌的作用较第三代头孢菌素弱

答案

参考答案:D

问答题
阅读理解

In the near future,we may be using our eyes to operate our smart-phones and tablets,even when it comes to playing popular games like Fruit Ninja.

The Gaze Group has been developing eye-controlled computer technology for nearly 20 years.But those devices have been firstly designed to help those with disabilities,and are very expensive.

“After a while,we figured out that probably the best way is to go for a mass-market way,” says Gaze’s Sune Alstrup Johansen.“where everybody would have this available."

Johansen and some of his colleagues have formed a new company,the Eye Tribe,which is hoping to develop the technology on a mass commercial level.

The technology works with the help of the computing device toward the user’s face. After making sure of the user’s eye movements,the technology is then able to easily find where a person’s eyes are moving,and then allow the eyes to control a cursor(光标).

“Our software can then determine the location of the eyes and know where you’re looking on the screen to make sure what you’re looking at,“reads an explanation on the Eye Tribe site.

There has been a gradual change toward hands-free technology in recent years, particularly in the gaming world.Recently Xbox released the Kinect device,which lets users control their Xbox and play certain games using only their hands,legs and voices. But still,most of these devices have been more of a gimmick than a practical way to use one’s hands to control a mobile device.Johansen said a replaceable filter(滤光器)would be a cheap,convenient way for most consumers.

And even as companies like The Eye Tribe work to create such a product for the average user, making the eye-controlled technology more accessible and less expensive will have similar benefits for physically disabled users.

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小题1:Which of the following is the main idea of the passage?

A.An introduction of a new device.

B.An introduction of smart-phones.

C.An introduction of eye-controlling technology.

D.An introduction of a new technology for the disabled.小题2:The underlined word“gimmick” probably means         .

A.a trick

B.a way

C.a lie

D.a dream小题3:According to the passage,we can learn that      .

A.the eye-controlling technology was first developed for the blind

B.the present developing 0f the technology will bring no good

C.there is no such a phone as we can use only with our eyes at present

D.the eye-controlling technology is only intended for the disabled people小题4:This passage is probably taken from         .

A.an experiment report

B.a science fiction

C.a school textbook

D.a science website