什么是静脉麻醉？有何优缺点？

两个物体A、B的质量分别为m₁和m₂，并排静止在水平地面上，用相同的水平拉力F同时分别作用于物体A、B上，分别作用一段时间后撤去，两物体各自滑行一段距离后停止，两物体A、B运动的图像分别如图a、b所示。已知拉力F撤去后，物体做减速运动的图像彼此平行，由图中信息可得：

A．m₁＞m₂

B．t=3s，物体A、B再次相遇

C．拉力F对物体A所做的功较多

D．拉力F对A的最大瞬时功率是对物体B最大瞬时功率的倍

变应性血管炎是哪一型变态反应

A．速发型 

B．细胞毒型 

C．免疫复合物型 

D．迟发型 

E．细胞毒型与免疫复合物型

阅读理解。

     Even when you're extremely busy, you aren't using your time with 100% efficiency. There are

gaps in everyone's schedule where they aren't doing anything important. Even if your schedule has

no gaps, there is probably lots of time where you aren't working as fast or as effectively as you

possibly could.

     Why aren't you completely efficient? It's because time isn't the limiting factor. If it were the

limiting factor, people could work non-stop without breaks or any unproductive distractions(消遣).

Instead, people, even those who are highly productive, need to take breaks, occasionally

procrastinate(拖延) and slow down on tasks throughout the day.

     The real and most important limiting factor for productivity is your energy levels to pay attention.

Energy levels limit your productivity because when you're tired, you can have ample time and still

not get everything done. Your attention ability is also limited, because even if there are a million

things that need to be done, you can only focus on one or two at a time.

     You might not be able to insert another 4-5 hours into your schedule without making some

sacrifices(牺牲). But even extremely busy people can add an hour or two into their schedule

without cancelling anything. The reason it's hard to "find time" isn't a lack of time. It's because

you don't have enough energy left to focus on something else that needs to fit into your day.

     I first suspected time wasn't the real problem during an extremely busy period in my life over

a year ago. I was insanely busy, but at that time I still exercised regularly. I had daily to-do lists

with over twenty items, and I still found time to exercise. However, after a few weeks off, due to

illness, I stopped exercising. I was not busy by any standards, in fact, my schedule was incredibly

light. Despite this free time, I found it hard to find time to exercise. It seemed to get pushed later

and later into my schedule until it was gone. How can I explain this odd experience? I believe y

ou have known it.

1. If someone can't work with 100% efficiency, the most important limiting factor is ________.

A. a schedule without gaps           

B. breaks and distractions

C .the limited time                      

D. the limited energy

2. According to paragraph 4, everyone, including the extremely busy people, can ___________.

A. work without any rest                 

B. focus on many things at a time

C. find some more time in a day            

D.do some exercise regularly

3. After a few weeks off, what was the change of the writer's life?

A. He had a longer daily to-do lists with over twenty items.

B. He stopped doing exercise because of the lack of energy.

C. He found it hard to find time to exercise because he was busier.

D. He pushed most of the things later and later in his schedule.

4. The writer gives the example of himself in the last paragraph in order to ___________.

A. prove what the real limiting factor is  

B. show us how busily he needs to work

C. explain how important a healthy body is  

D. tell us what an odd experience he has

5. What is the best title of the passage?

A. Are You Really Lack of Time?          

B. How Can You Work Efficiently?

C. What Makes Your Energy Limited?      

D. When Should You Do Exercise?

鼻内镜脑脊液鼻漏修补术修补蝶窦脑脊液鼻漏时，由内至外放置材料的最佳顺序是（）。

A.阔筋膜、明胶海绵、碘仿纱条、肌肉

B.明胶海绵、阔筋膜、碘仿纱条、肌肉

C.阔筋膜、肌肉、明胶海绵、碘仿纱条

D.肌肉、阔筋膜、明胶海绵、碘仿纱条

E.肌肉、阔筋膜、碘仿纱条、明胶海绵

根据《关于印发游艇安全管理工作实施意见的通知》，下列哪些机构可办理非本地住所的个人所拥有游艇的船舶登记手续？（）

A.海南海事局

B.厦门海事局

C.温州海事局

D.珠海海事局