关于鼻与鼻窦CT扫描技术，叙述错误的是（）。 A.轴位扫描患者仰卧，先扫头颅侧位定位

简述分拣管理信息系统中管理层，执行层，控制层三者之间的关系。

Social networking isn't only for the under 40s. More than 25 percent of Americans 50 years and older stay connected using sites such as Facebook, MySpace and Twitter, according to new research.

"The latest data tells us that more and more social networking is becoming a part of everyday life for Americans 50 plus," said Kevin Donnellan, the chief communications officer at AARP, which released the report.

Nearly a quarter of older Americans are on Facebook and 73 percent said they use it to stay in touch with relatives, but not just their children and grandchildren. "They are using the Internet to keep up with the world and the people who are important to them," said Jean Koppen, the author of the report. She added that older adults are also on Facebook to stay connected, not only with their family, but with their friends and peers. Almost 50 percent of older adults were introduced to the social networking sites by a family member, mainly a child or grandchild. "Just under one-fifth of adults aged 50 and older say they do not use the Internet," according to the report.

The findings are based on a telephone survey of 1,863 adults. In addition to keeping up on Facebook and Twitter older adults are also aware of the latest technology. Eighty-three percent had heard about the Apple iPad and 11 percent intended to buy one.

小题1:What’s the main idea of the passage?             

A.       Social networking isn’t for the under 40s in the U.S.A.

B.       American old people’s way of life is quite fashionable.

C.       The Internet is also popular among the American over 50s.

D.       Facebook, MySpace and Twitter are hot websites in America.

小题2:Which of the following statements is TRUE according to the passage?    

A．Nearly 2000 adults took part in the survey on line.

B．The over 50s were introduced to the Internet by the young.

C．About 20% of adults aged 50 and older don’t like the Internet.

D．Many Americans 50 plus stay connected using the Internet.小题3:What’s the underlined sentence used for?    

E.                   It’s used as a reason for the popularity of the Apple iPad in America.

F.                   It’s used as an example of the older adults’ awareness of the latest technology.

G.                  It’s used as a suggestion to the readers who are interested in the IT products.

H.                  It’s used as a choice for the Americans intending to use Social networking.

小题4:Where can we most probably read this passage?    

I.                     In an experiment introduction.

J.                    In a computer magazine.

K.                  In a product advertisement.

In a news report

采用微量淋巴细胞毒试验，使用抗HLA-DR血清或抗HLA-DQ血清进行定型，使用的细胞通常是（）。

A.红细胞

B.B细胞

C.T细胞

D.血小板

E.嗜酸性粒细胞

The first mention of slavery in the statutes of the English colonies of North America does not occur until after 1660--some forty years after the importation of the first Black people. Lest we think that slavery existed in fact before it did in law, Oscar and Mary Simon assure us that the status of Black people down to the 1660’s was that of servants. (46) A critique of the Simons’ interpretation of why legal slavery did not appear until the 1660’s suggests that assumptions about the relation between slavery and racial prejudice should be reexamined, and that explanations for the different treatment of Black slaves in North and South America should be expanded.
(47) The Simons explain the appearance of legal slavery by contending that, during the 1660’s, the position of White servants was improving relative to that of Black servants. Thus, the Simons argue, Black and White servants, heretofore treated alike, each attained a different status. There are, however, important objections to this argument. First, the Simons cannot adequately demonstrate that the White servant’s position was improving during and after the 1660’s; several acts of the Maryland and Virginia legislatures indicate otherwise. Another flaw in the Simons’ interpretation is their assumption that prior to the establishment of legal slavery there was no discrimination against Black people. It is true that before the 1660’s Black people were rarely called slaves. But this should not overshadow evidence from the 1630’s on that points to racial discrimination without using the term slavery. Such discrimination sometimes stopped short of lifetime servitude or inherited status--the two attributes of true slavery--yet in other cases it included both. (48) The Simons’ argument excludes the real possibility that Black people in the English colonies were never treated as the equals of White people.
This possibility has important ramifications. (49) If from the outset Black people were discriminated against, then legal slavery should be viewed as a reflection and an extension of racial prejudice rather than, as many historians including the Simons have argued, the cause of prejudice. In addition, the existence of discrimination before the advent of legal slavery offers a further explanation for the harsher treatment of Black slaves in North than in South America. (50) Frey and Terry have rightly argued that the lack of certain traditions in North America--such as a Roman conception of slavery and a Roman Catholic emphasis on equality--explains why the treatment of Black slaves was more severe there than in the Spanish and Portuguese colonies of South America. But this cannot be the whole explanation since it is merely negative, based only on a lack of something.