一政府机构出版了航空公司的信用等级，把晚点航班比例最小的航空公司列入最高信誉等级，该

（）是火灾自动报警系统中用以接收、显示和传递火灾报警信号，并能发出控制信号和其他辅助功能的控制指示设备。

A、火灾探测器

B、火灾报警装置

C、火灾警报装置

D、火灾报警按钮

患者，男性，45岁。阵发性全腹疼痛3天，加剧1天。呕吐数次，未排便排气。2年前曾行阑尾切除术。查体：血压100/60mmHg，体温37.6℃，腹稍胀，未见蠕动波，未触及包块，肠鸣音亢进，可闻及气过水声，血红蛋白160g/L，白细胞10.6×10⁹/L。

可能性最大的诊断是（）。

A.肠套叠

B.肠系膜血栓形成

C.小肠扭转

D.麻痹性小肠梗阻

E.单纯性低位小肠梗阻

旋涡泵与离心泵主要差别在于（）。

A、口环结构

B、叶轮安装方式

C、叶轮结构

D、轴套不同

当细菌量大组织敏感性高时，组织出现（）。

A．血性渗出 

B．肉芽肿 

C．干酪样物质 

D．结核结节 

E．局部组织坏死

A bite of a cookie containing peanuts could cause the airway to constrict fatally. Sharing a toy with another child who had earlier eaten a peanut butter and jelly sandwich could raise a case of hives. A peanut butter cup dropped in a Halloween bag could contaminate the rest of the treats, posing an unknown risk.

These are the scenarios that "make your bone marrow turn cold" according to L. Val Giddings, vice president for food and agriculture of the Biotechnology Industry Organization. Besides representing the policy interests of food biotech companies in Washington, D. C., Giddings is the father of a four-year-old boy with a severe peanut allergy. Peanuts are only one of the most allergenic foods; estimates of the number of people who experience a reaction to the beans hover around 2 percent of the population.

Giddings says that peanuts are only one of several foods that biotechnologists are altering genetically in an attempt to eliminate the proteins that do great harm to some people’s immune systems. Although soy allergies do not usually cause life-threatening reactions, the scientists are also targeting soybeans, which can be found in two thirds of all manufactured food, making the supermarket a minefield for people allergic to soy. Biotechnologists are focusing on wheat, too, and might soon expand their research to the rest of the "big eight" allergy-inducing foods: tree nuts, milk, eggs, shellfish and fish.

Last September, for example, Anthony J. Kinney, a crop genetics researcher at DuPont Experimental Station in Wilmington, Del., and his colleagues reported using a technique called RNA interference (RNAi) to silence the genes that encode p34, a protein responsible for causing 65 percent of all soybean allergies. RNAi exploits the mechanism that cells use to protect themselves against foreign genetic material; it causes a cell to destroy RNA transcribed from a given gene, effectively turning off the gene.

Whether the public will accept food genetically modified to be low-allergen is still unknown. Courtney Chabot Dreyer, a spokesperson for Pioneer Hi-Bred International, a subsidiary of DuPont, says that the company will conduct studies to determine whether a promising market exists for low allergen soy before developing the seeds for sale to farmers. She estimates that Pioneer Hi-Bred is seven years away from commercializing the altered soybeans.

Doug Gurian-Sherman, scientific director of the biotechnology project at the Center for Science in the Public Interest—a group that has advocated enhanced Food and Drug Administration oversight for genetically modified foods—comments that his organization would not oppose low-allergen foods if they prove to be safe. But he wonders about "identity preservation" a term used in the food industry to describe the deliberate separation of genetically engineered and no nengineered products. A batch of nonengineered peanuts or soybeans might contaminate machinery reserved for low-allergen versions, he suggests, reducing the benefit of the gene-altered food. Such issues of identity preservation could make low-allergen genetically modified foods too costly to produce, Chabot Dreyer admits. But, she says, "it’s still too early to see if that’s true. \

According to the text, foods have been genetically altered to（）

A. taste more delicious

B. to cure people’s ineffectiveness in immune system

C. to promote sales of peanut

D. to lower the chance to get allergy