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PROTECTING EYES FROM COMPUTER SCREENS Many of us spend the bulk of the day looking at computer screens. Reading this article means there’s a good chance you’re looking at one right now. But does looking at computer screens damage your eyes? Professor Nathan Efron does not consider computer screens “harmful” to our eyes. But he admits if you use one a lot, you increase your risk of becoming slightly more short-sighted –where your eyes focus well only on close objects while more distant objects appear blurred. This is especially the case for children and young adults, whose eyes are still developing. In the shorter term, prolonged viewing of a computer screen can make any slight existing vision defects more noticeable. It can also give you what is sometimes known as “computer vision syndrome” – eye strain, headaches, gritty eyes and blurry vision. But this is only temporary and can be minimized by: Adjusting the screen display so the contrast is high and the brightness feels comfortable. Having lighting that does not produce glare on the screen. Giving your eyes regular rests from looking at the screen (The Optometrists Association of Australia recommends you do this for five to ten minutes every one to two hours of computer use. It's a good time to make phone calls or do other tasks.) 1. Many of us spend much time looking at computer screens. {T; F} 2. Looking at computer screens for long time doesn’t damage children and young adults’ eyesight. {T; F} 3. Computer vision syndrome cannot be weakened. {T; F} 4. It’s good taking breaks during screen watching. {T; F} 5. Proper lighting is important to protect our eyes. {T; F}
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A.
报告 撰写 显示
B.
撰写 显示 报告
C.
撰写 报告 显示
D.
显示 报告 撰写
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奎宁
B.
环丙沙星
C.
利福平
D.
甲硝唑
E.
益康唑
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A.
使用FTP软件上传
B.
使用“兼职”的FTP软件上传
C.
使用Web页面上传
D.
通过E-mail上传
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A.
青蒿素
B.
青霉素
C.
链霉素
D.
土霉素
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A.
黄韧带
B.
棘间韧带
C.
后纵韧带
D.
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E.
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A.
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B.
电子邮件
C.
网上投稿系统
D.
纸质手写稿邮寄
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A.
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B.
棘间韧带
C.
棘上韧带和项韧带
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A.
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B.
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C.
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D.
矮茎豌豆的基因组成总是纯合体
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