角膜挫伤不会出现（） A.角膜上皮缺损 B.角膜基质水肿 C.后弹力层皱褶 D.瞳孔

A. A=9, B=4    

B. A=7, B=6    

C. A=8, B=5

一辆玩具赛车的车轮半径是2.5厘米，转速是每分钟4000圈，比赛的赛程是500米．这辆赛车1分钟能到达终点吗？

简述涂层（Teflon涂料）的六大特性。

Small, pink and very ugly. Hardly the qualities of a star, but they describe the deformed mouse that was the media darling at a recent science exhibition in Beijing. With a complex tissue structure in the shape of a human ear grafted on to its back, the rosy rodent was a stunning symbol of the serious strides China is making in the field of biotechnology.

China is fast applying the latest life-science techniques learned from the West to aggressively pursue genome research. It’s establishing its own centers of technical excellence to build a scientific base to compete directly with the United States and Europe. With a plentiful supply of smart young scientists at home and lots of interest abroad biotechnology is on the brink of a boom in China. And in the view of foreign scientists, Beijing is playing a clever hand, maximizing the opportunities open to them.

For the moment, the cooperation exists mostly with Europe and the U. S. But Asia’s other biotech leaders, Japan, Singapore and Korea, also are recognizing China’s potential as an attractive low-cost base to conduct research. These partnerships—and China’s advancement in the field of biotechnology—could help benefit the rest of Asia: China’s rapid progress in improving crop yields will address food-security concerns in the region. In addition, China is more likely to focus on developing cheap technology that its predominantly poor population and those of other Asian countries—can afford.

There remain, however, serious barriers to the development of a p biotech industry. Among them are a poor domestic legal framework, weak enforcement of intellectual-property rights and loose adherence to international standards. China is a signatory of the International Bio Safely Protocol, which should mean adherence to global standards governing the conduct of field trials. But some observers are skeptical. "The regulations look good, but I haven’t met one scientist who believes they are being fully adhered to," says a European science analyst.

If shortcuts are taken, then some of the recent scientific achievements trumpeted in the official press may never make it to market. But no matter how strict lab test are, other problems lie in wait. For example, there is a number of tasks it would take years to fulfill in the patents office, says one lawyer, leaving innovators with little protection if they take a product to market in China.

In the field of biotechnology China is thought to ().

A. have been making an utmost effort learning from the West

B. have become a country among the advanced

C. have been able to rival the United States and Europe

D. have launched a biotechnological revolution

氧化硅以铝硅酸钠形式析出速度随温度升高而增加，随浓度降低而降低。