属蜜蜂细菌性疾病，主要发生于2～4日龄的小幼虫的是（） A.蜜蜂白垩病  B.欧洲幼

某天六（1）班有49人到校上课，有1人请病假，这一天的出勤率是（    ）。

女性，40岁。反复腹痛、发热、黄疸1年，近3天上述症状加重，高热黄疸不退。查体：T40℃，脉搏120次/分，血压70/50mmHg。该患者首选的治疗为（）。

A.立即手术

B.全胃肠外营养后手术

C.积极抗休克同时及早手术

D.大剂量抗生素治疗感染后择期手术

E.应用血管收缩剂，血压升至正常后及早手术

阅读理解。

     Giving your child a chocolate bar for him to finish his maths homework is an excellent idea, according to

researchers who claim that the yummy treat could improve the brain's ability to do the most "dreadful" subject.

The study, presented at the British Psychological Society annual conference, is great news for students who

binge on(暴食) chocolate when revising for exams. For the study 30 voluhteers were asked to count backwards

in groups of three from a random number between 800 and 999 generated by a computer. The findings show

that they could do the calculations more quickly and more accurately after they had been given the cocoa drink.

However,the same was not true when the group was asked to count backwards in groups of seven, which the

researchers described as a more complex task, requiring a slightly different part of the brain. The findings also

show that the volunteers did not get as tired doing the calculations if they bad heen given the cocoa drink despite

being asked to do them over and over for an hour. The flavanols (黄烷醇) work by increasing the flow of blood

into the brain. Dark chocolate contains higher quantifies of the chemical than plain or milk chocolate. Prof.

David Kennedy at Northumbria University said that chocolate could be beneficial for mentally challenging tasks.

The researchers gave the volunteers a total of 500 mg of flavanol. Although the amount was too great to be

found naturally in the diet, researchers said that people should ensure that they have lots of flavanols. "The

more fruit and vegetables and things that are high in flavanols, the better that is for your brain in the long run."

1. The researchers tend to think that _____.

A. chocolate is good for children's health

B. delicious food improves the brain's ability

C. maths is difficult for children to learn

D. all students like eating chocolate for exams

2. How did the volunteers' calculations get improved after the drink?

A. Hot drink helps students operate computers fasten.

B. Hot drink is likely to speed up the brain's activity.

C. The flavanols help more blood flow into the brain.

D. The flavanols are chemicals that make people relaxed.

3. Which of the following contains the most flavanols?

A. Dark chocolate.

B. Plain chocolate.

C. Milk chocolate.

D. Fruit.

4. It can be concluded from the last paragraph that _____.

A. flavanols can help solve more complex problems

B. lower doses of flavanol have no effect on the brain

C. people should eat more vegetables instead of chocolate

D. students should have enough flavanols in the daily diet

球墨铸铁焊接时，产生裂纹的可能性比灰铸铁（）

A.大得多

B.小得多

C.一样

D.以上均有可能

人民警察的法律素质，是人民警察依法履行职责、行使职权所应具备的法律意识、法律知识和执法技能的综合体现。 ( )