对某一疾病危险因素研究,某因素在病因学上与疾病无关联,但可以引起所研究疾病的症状,从

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问题:

对某一疾病危险因素研究,某因素在病因学上与疾病无关联,但可以引起所研究疾病的症状,从而提高了该疾病的检出率,引起对该无关因素的过高估计,这种偏倚是()

A.奈曼偏倚 

B.排出偏倚 

C.混杂偏倚 

D.检出偏倚 

E.易感性偏倚

考点:环境卫生(医学高级)环境与健康的关系环境与健康的关系题库
题型:单项选择题

一物体做匀加速直线运动,在某时刻前的t1时间内位移大小为s1,在该时刻后的t2时间内位移大小为s2,则物体的加速度大小为(  )

A.

2(s2t1-s 1t2)
t1t2(t1+t2)

B.

s2t1-s1t2
t1t2(t1+t2)

C.

2(s1t2-s2t1)
t1t2(t1+t2)

D.

s1t2-s2t1
t1t2(t1+t2)

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在真空密闭容器中加入 a mol PH4I固体,在一定温度下发生反应:

PH4I(s)

PH3(g )+HI(g),4PH3(g)

P4(g )+6H2(g),

2HI(g)

H2(g )+I2 (g) 以上三个反应建立平衡后,测得HI为b mol,I2 (g)为c mol,H2 为d mol.

求:①平衡后,容器内P4(g)和PH3的物质的量(用代数式表示):n (P4)=______,n (PH3)=______.

②a、b、c 三者的关系服从 a>______(填b、c的代数式).

题型:单项选择题

健美操的主要特点()。

A、健身美体的实效性

B、节奏鲜明的时代性

C、健心娱乐的群众性

D、大众参与性

题型:单项选择题

Goal chances came and goal chances went. But two of the world’s highest ranked teams—with some of football’s highest paid players—couldn’t get the ball into the net. And they were playing against sides that only just made it to the World Cup.

With two defeats, one draw and no goals, France collected its newest title since rising to the top of the game four years ago: The worst defending champion in World Cup history.

"I’m very disappointed, and it’s the end of a beautiful story," said a French striker David Trezeguet. "The story began in 1998 and ended today against Denmark. "

France won the 2000 European Championships and was ranked the best team on the planet before the World Cup.

Besides the goalposts and crossbars seeming to be against this unlucky team, France’s game plan has been the same for four years so opponents know it by heart.

Senegal, an African team playing in its first World Cup, surprised everyone by beating France in the opening World Cup match before entering the second round successfully. Uruguay and Denmark followed a similar strategy to stop France, creating a defensive barrier and launching many counter attacks.

Following France, Argentina became the second big name to take an early plane home from this year’s World Cup.

The South Americans were expected to become world champions for a third time. This was particularly because of an impressive display when they lost just one of their 18 qualifying matches.

The team’s 1-0 loss to England on June 7 was the beginning of a nightmare for the players. But even after this surprising defeat, they never thought that they would be going home so soon.

But a 1-1 draw in Argentina’s final group match against Sweden made the unexpected a reality.

From the passage we know ().

A.France was defeated first by Denmark

B.Uruguay beat France and was defeated by Denmark

C.England beat Argentina and drew the next one

D.Sweden didn’t beat Argentina but kicked it out

题型:单项选择题

乳漏常用的外治法:()

A.腐蚀法

B.垫棉法

C.切开疗法

D.挂线疗法

E.以上都是

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