问题 问答题 简答题

彩色多普勒超声(彩超)的临床用途有哪些?

答案

参考答案:

彩超除可进行普通的超声检查外,还具有以下特殊用途:

①心脏血管形态学、血液流体力学检查:在对心脏、血管病变的检查、诊断中,可获得广泛而可靠的先天性和获得性心脏病的诊断信息。彩色多普勒能量图描绘血管轮廓,显示血管腔内外的病变,确定狭窄的部位和原因。②实质性脏器血管形态学、血液流体力学检查:可用于实质性器官血流灌注的检测。彩色多普勒能量图能敏感地显示肾皮质内小叶间动脉,当移植肾急性血管性排异时,彩色多普勒能量图显示肾血管树彩色血流明显减少,甚至消失;同时利用彩色多普勒血流显像(CDFI)测得的阻力指数(RⅠ)进行鉴别,可提高对肾排异诊断的敏感性和特异性。研究表明,恶性肿瘤能通过释放一种“肿瘤血管生成因子”,建立丰富的肿瘤内微循环,这种多血供的病理特点有别于良性肿瘤。例如,高分辨率二维黑白超声仪虽能显示肝内5-10mm的病变声像,但较难作出鉴别诊断,当彩超检查显示病变内部或边缘处高速血流时,则提示早期肝细胞癌的可能性大。多血管型肝癌适合于选择肝动脉栓塞(TAE)治疗,肝动脉栓塞后检查,肿瘤血供减少表明治疗有效。如发现栓塞的肿瘤供血血管重新开放,可作为判断癌瘤复发的一项有效筛选指标。③非液流体力学检查:利用彩色多普勒血流显像检测非血液性的流动性液体的信号,如观察膀胱输尿管入口处喷尿情况,

以鉴别输尿管有无梗阻存在。④其他用途:可用于阻塞性黄疸患者检查时对于扩张的胆管与肝内血管的鉴别。

阅读理解

阅读理解。

     US government date reveals that up to 44% of the US workforce is single-and it may be because of

work. Here are four reasons why your job might be keeping you single and what to do about it.

     1. "I don't have time to date." Many people who are single say their jobs don't leave them with

enough time to meet Mr. or Mrs. Right. You may have made a conscious decision to make career

your No.1 priority(优先). Or it may be that pursuing your dream job is easier than pursuing your dream

partner. Whatever the reason, spending too much of your time and energy on your career will cause your

dating life to flounder(折磨).

     2. "My boss knows I'm single and singles me out." Singles are often expected to work late,

travel for business, and take on last minute assignments because they don't have "family commitments

(义务)". For example, Pennsylvania Governor Ed Rendell stated last year that the choice of Janet

Napolitano as Homeland Security Secretary was an excellent one because she has "no family and no

life" and could devote 19-20 hours a day to the job.

     3. "Everyone I know is taken/ married/coupled up." While this may not seem to be a job related

issue, it could be. Statistics show that nearly half of all married couples met at work. So you're at a

disadvantage if your work doesn't provide you with opportunities to meet and hang out with other singles.

      4."No one wants to date a …" unfortunately, some jobs come with certain stereotypes (陈词滥

调) that can make an expected date a complete failure. For example, being a lawyer or doctor could

make you an unwelcome person because nobody's idea of a good date is to argue or be psychoanalyzed(用精神分析疗法治疗分析)!

1.Which of the following is NOT a reason why 44% of the US workforce is single?

A. Singles are often given more work.

B. Some jobs seem to prevent one from dating successfully.

C. They are too busy with their work.

D. Many people don't know how to make themselves look attractive.

2."Mr. or Mrs. Right" in the second paragraph means_________.

A. an ideal husband or wife

B. a certain Mr. or Mrs. Right

C. a reliable person

D. one's colleague

3. If your friend is single due to the second reason, what do you say to him/her?

A. Make dating your work.

B. Tell your boss that you already have plans.

C. Create your own dating pool.

D. Be yourself, not your job.

单项选择题