问题 单项选择题

心动周期中,室内压升高速率最快的时相是()

A.心房收缩期

B.等容收缩期

C.快速射血期

D.减慢射血期

E.快速充盈期

答案

参考答案:B

解析:心室收缩期包括等容收缩期以及快速、减慢射血期。(1)等容收缩期 心室开始收缩,室内压尚低于主动脉压,半月瓣仍处于关闭状态,心室成为一个封闭腔。虽然心室收缩,但心室容积没有改变,故称等容收缩期。(2)射血期 等容收缩期间室内压升高超过主动脉压时,半月瓣被冲开,等容收缩期结束,进入射血期。此期室内压继续上升达峰值。心室舒张期包括等容舒张期和快速、减慢充盈期。(1)等容舒张期:心室肌开始舒张后,室内压下降,主动脉内血液向心室方向返流,推动半月瓣关闭;此时室内压仍高于房内压,房室瓣依然处于关闭状态,心室又成为封闭腔。心室肌舒张,室内压急速大幅度下降,但容积并未改变。这段时期称为等容舒张期。(2)充盈期:当心室压降到低于房内压时,房室瓣开启,心室充盈开始,血液顺着房-室压力梯度快速流入心室,称此期间为快速充盈期。

阅读理解

A businesswoman, a mother of four, an international fashion icon(偶像) , a woman committed to making the world a better place for women and children—Queen Rania of Jordan is truly changing the world.

Rania was bom in Kuwait, in 1970.Shortly after Iraq invaded that country in 1990, her family fled and settled in Jordan.After graduating from a business school, Rania became successful in the business world.

When she was just 22, she went to a dinner party that changed her life forever.It was there that she met Jordan' s Prince Abdullah.Six months later, Rania and Abdullah had a royal wedding and started a family.

After the death of her father – in – law, King Hussein, in 1999, Prince Abdullah was crowned King Abdullah II of Jordan, and Rania became the world' s youngest living queen.

In her role as Queen, Rania has become well known around the world for her charity work and her efforts to improve educational opportunities for girls.She is an outspoken advocate of women' s rights, education reform, and child abuse.She is also well - known for her efforts to remove Western stereotypes (旧观念) about the Muslim world.

Rania explains that there is a direct relationship between increasing education and eliminating poverty." You can change the course of a nation through education," she says." One of the most important things you can do for a girl is empower her with her education.Once she has the education she can then have control over her income, she can change her life, she can have choices."

In the future, Rania says, she hopes for a more open and secure world."We look at problems happening halfway across the world and we think,' Well, that' s their problem.' But it' s not," she says." When you solve somebody else' s problem, you are solving a problem for yourself, because our world today is so interconnected."

小题1:Rania and her family moved to Jordan because ____.

A.she was engaged to Jordan' s Prince Abdullah

B.she wanted to attend a business school there

C.Jordan was a more developed country than Kuwait

D.the war broke out between Kuwait and Iraq小题2:Rania became the world' s youngest living queen when she was ____.

A.a girl of 22

B.at the age of 23

C.in her thirties

D.29 years old小题3:In her role as Queen, Rania is more devoted to ____.

A.her business work

B.girls' education

C.fashion shows

D.her family小题4:Rania thinks that ____.

A.women have brought about great changes to the world

B.education can help a girl find a wealthy husband

C.in the world today, all countries depend on each other

D.the Muslim world needs more help from the western countries小题5:The text mainly describes Rania as ____.

A.a caring mother

B.a fashion model

C.a social activist

D.a smart businesswoman

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