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【单选题】
某地区对心血管系统疾病的研究中发现：男性居民在队列研究中，具有高胆固醇水平者，患冠心病的RR值为2.4；而在病例对照研究中，病例组与对照组却无明显差异(OR值=1.6)。进一步分析发现，患冠心病的患者在被诊断为该病后，开始戒烟、改变饮食习惯等，使血中胆固醇水平降低。造成两研究结果差异的原因是A.
Perkson’s偏倚
B.
检出症候偏倚
C.
混杂偏倚
D.
易感性偏倚
E.
信息偏倚
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【简答题】The parents are talking about giving their 1 a proper name. The mother doesn't like the name Amber because it is a 2 name. They decide their baby will be called 3 because it is a(n) 4 name.Suddenly th...
【单选题】某分部工程双代号网络计划如下图所示，根据下表给定的逻辑关系和双代号网络计划的绘图规则，其作图错误问题是（ ）。
A.
节点编号不对
B.
逻辑关系不对
C.
有多个起点节点
D.
有多个终点节点
【简答题】A Little girl lived with her grandmother after her parents died. They slept in an upstairs bedroom. One night there was a big fire in their house. The whole house was burning. The little girl appeared...
【简答题】I reached —— to touch the little boy when he suddenly felt very sorry and about to cry.
【单选题】The' eye-on-the-consumer' approach ______.
A.
is an outmoded marketing concept
B.
means consumer satisfaction is more important than profit in a company
C.
means marketing and selling are different
D.
means companies should cater to consumers
【多选题】下列关于双代号网络计划绘图规则的说法，正确的有( )。
A.
网络图必须正确表达各工作间的逻辑关系
B.
网络图中可以出现循环回路
C.
网络图中一个节点只有一条箭线引入和一条箭线引出
D.
网络图中严禁出现没有箭头节点或没有箭尾节点的箭线
E.
单目标网络计划只有一个起点节点和一个终点节点
【简答题】网络拓扑结构主要有 、 、 、树型和网状拓扑结构。
【单选题】Bill was given a chair and asked to wait a little as darkness came on, then suddenly the whole bridge was outlined in lights.
A.
天快黑了，有人给比尔一把椅子，请他坐下等一会儿。忽然电灯全亮了，整座大桥的轮廓被灯照了出来。
B.
给比尔一把椅子，他被要求坐下等一会儿，天快黑了。忽然电灯全亮了，照出了整座大桥的轮廓。
C.
天快黑了，有人给比尔一把椅子，请他坐下等一会儿。忽然电灯全亮了，照出了整座大桥的轮廓。
D.
给比尔一把椅子，他被要求坐下等一会儿，天快黑了。忽然电灯全亮了，整座大桥的轮廓被灯照了出来。
【简答题】Technology, entrepreneurship and innovations are keywords that sum up the new era. The Internet is not just a technology, it is also about marketing. Companies which do not use the Net as a marketing ...
【简答题】marketing is a means for enterprises to promote products and brands through instant messaging tools.
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