下列关于样品的加入和洗脱的操作不正确的是 [ ] A.加样前,打开色谱柱下端的流

题型:选择题

问题:

下列关于样品的加入和洗脱的操作不正确的是  [ ]

A.加样前,打开色谱柱下端的流出口,使柱内凝胶面上的缓冲液缓慢下降到凝胶面的下面

B.加样后,打开下端的出口,使样品渗入凝胶床内

C.等样品完全进入凝胶层后,关闭下端出口

D.用吸管小心地将1mL透析后的样品加到色谱柱的顶端,不要破坏凝胶面

考点:血红蛋白的提取和分离
题型:选择题

阅读短文,选择正确答案。

    Yesterday the police were joined by more Yesterday the police were joined by more than 20 volunteers in the

continuing search for the two missing teenagers, Vicky Gray and Tom Hunter, and their guide, Gavin Jones. The

police said that they had disappeared during an adventure (冒险) tour of Cape York Peninsula.

    This was the second day of the search and the police were now very worried about the safety of the three

missing people.

    The police said that the search had covered a wide area, but the rainforest was thick and their work was

made harder by the recent rain. Later on Chief Inspector (警官) Roger Fleet said, "The travellers had a ridio

with them. If they had been in trouble, they would have called us." 

    The three travellers left Cooktown very early on Saturday morning in a Toyota car. They took a small dirt

road that runs down to the Daintree River, a dangerous river full of crocodiles (鳄鱼). Chief Inspector Roger

Fleet said the tourists wouldn't have got into trouble if they had stayed on the main road.

    A photo of Vicky and Tom was found by a policeman under the "Be Careful about crocodiles" sign near the

river. Why was the photo left behind? This is just one of the unanswered questions. Other questions are: Why

was the photo left behind? Why was the Toyota parked and locked at the edge of the rainforest? The police said

that the travellers had left a map of the area behind. Why? Why had someone drawn a cross on the point (地点)

where the car is? Is this a sign? What does it mean? If anyone can give information or has seen these three

young people, contact the local police in Cooktown.

1. This article is probably taken from ________. [ ]

A. a newspaper

B. a magazine

C. a storybook

D. a guidebook

2. Which word best describes the search of the three missing people? [ ]

A. Helpless

B. Hard

C. Delightful

D. Successful

3. Which of the following things wasn't found by the police? [ ]

A. A touring map.

B. A photo of the travellers.

C. The travellers' radio.

D. The travellers' car

4. All the following are unanswered questions except ________. [ ]

A. why they left a photo behind

B. why they came to this area

C. why their Toyota was parked in the place

D. why a cross was drawn on the map

5. The article asks people to ________. [ ]

A. join the police in searching for the missing people

B. tell the police about the travellers' ages and their appearance

C. learn the lesson and stop taking adventure tours

D. provide information about the missing people

题型:选择题

全国药品检验的最高技术仲裁机构,是全国药品检验所业务技术的指导中心 ()

A.药事管理体制

B.药品技术监督机构

C.中国药品生物制品检定所

D.国家经贸委医药司的职能

E.DEA

题型:选择题

甲亢与单纯甲状腺肿鉴别,最主要在于前者()

A.I摄碘率增高

B.I扫描示甲状腺增大

C.BMR增高

D.131I曲线高峰不前移

E.3T抑制率<50%

题型:选择题

我国古代医学家扁鹊在2000多年前就已经用“切脉”诊断疾病。[ ]

题型:选择题

在操作系统中,用户对I/O设备的使用,通常采用( )。

A.物理设备名

B.逻辑设备名

C.虚拟设备名

D.设备牌号

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