对某样本的相关系数r和0的差别进行检验,结果t1<t0.05(n-2),因此()。A

题型:单项选择题

问题:

对某样本的相关系数r和0的差别进行检验,结果t1<t0.05(n-2),因此()。

A.两变量的差别无统计意义

B.两变量存在直线相关的可能性小于5%

C.两变量肯定不存在相关关系

D.两变量间存在相关关系

E.就本资料尚不能认为两变量存在直线相关关系

考点:公卫执业医师2008年公卫执业医师考试《卫生统计学》考试真题
题型:单项选择题

分析前阶段质量保证的主要目的是保证检验结果的()

A.准确性

B.重复性

C.再现性

D.稳定性

E.反映患者当前病情的真实性 

题型:单项选择题

关于输卵管妊娠的诊断哪项是错误的()

A.盆腔检查时宫颈可有举痛

B.后穹隆穿刺抽不出血液可排除异位妊娠

C. * * 有蜕膜管形排出有助诊断

D.输卵管妊娠破裂常有昏厥与休克

E.有时没有腹痛史诊断仍可成立

题型:单项选择题

阅读理解。

                                                  How to wash clothes in a flash

     LAUNDRY is never an easy part of housework. But if piles of sweaty (汗水浸湿的) T-shirts and

smelly socks drive you crazy, then two Chinese scientists might have the answer.

    Long Mingce and Wu Deyong of Shanghai Jiao Tong University have invented a kind of cotton that

cleans itself. No need for soap or water, the scientists say. All you have to do is put the clothes out in the

sun.

    According to the Guardian, this magical self-cleaning ability comes from a special chemical mixture.

The material is covered with this mixture. It can break down dirt and remove bad smells after only a few

hours in the sun.

    One of the chemicals is called titanium dioxide (二氧化钛). Scientists have known for some time that

titanium dioxide can clean fabrics (织物). However , it only works under ultraviolet (紫外的) light and so

is not yet widely used - ultraviolet light cannot be seen.

   "We knew that self-cleaning cotton fabrics with titanium dioxide coating had already been developed,

but they cannot work, or they work weakly, under sunlight," Long said. "If we want to use the fabrics in

daily life, we must develop cotton that cleans itself under daylight."

   The scientists worked hard for years to find a better chemical. Finally , they added silver iodide (碘化银) into the mixture. This made the chemical reactions in sunlight faster. The new mixture is also nearly

seven times better than the former one with pure titanium dioxide at removing dirt and killing bacteria.

   The experiment was only carried out on cotton clothing. However, according to Long, the technology

can be "applied to all kinds of fabrics and their related products." It is also cheap and environmentally

friendly , he said.

   The self-cleaning material is not yet ready for the market. Scientists still need to know whether it could

harm people. Although titanium dioxide is used in some foods, it can cause health problems if it gets into

the lungs (肺). Scientists need to make sure it is safe before we can start to enjoy the benefits of this

technology .

1. Thanks to this new discovery, we will be able to clean fabrics ___ .

A. using soap and water  

B. using silver iodide  

C. using sunlight        

D. using moonlight

2. In what way is the new material better than previous materials ?

A. It works using any kind of light.  

B. It works more quickly and effectively.

C. It is widely found in nature.      

D. It can be used for all kinds of fabrics .

3. What might be a problem with the self-cleaning material ?

A. It will cause pollution.          

B. It costs too much to produce.

C. It breaks down easily in the sun.  

D. It might cause health problems

4. Which of the following statements is TRUE? 

A. There may be many other kinds of self-cleaning fabric in the future .

B. We can already buy self-cleaning clothes on the market.

C. This was the first time that scientists discovered titanium dioxide.

D. Titanium dioxide is widely used in the food industry.

题型:单项选择题

某男,68岁,因咳嗽、发热三天,胸片示右下肺炎入院,查体:皮肤干燥,右下肺少许啰音。给予青霉素640万单位加入10%葡萄糖液中滴注,每天二次,二天后体温退,肺部啰音消失,感口干明显,嗜睡进而发展到昏迷状态,血压100/80mmHg,血常规正常,尿常规:蛋白:±,尿糖++++,尿酮体(-)。

此时应作哪一项检查()。

A.头颅CT

B.心电图

C.正侧位胸片

D.血糖、电解质

E.肝、肾功能

题型:单项选择题

墙、柱的()是保证砌体房屋稳定性与刚度的重要构造措施之一。

A.强度验算

B.高厚比验算

C.变形验算

D.裂缝验算

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