问题 问答题 简答题

血小板血型抗原可分几类?

答案

参考答案:

血小板血型抗原通常分为两类。

一类是血小板特异性抗原,主要是HPA-1~5,还有DUZOa抗原和PLE抗原。

还有一类称为血小板相关抗原,主要是与红细胞ABO血型系统和HLA有关,后者主要是在血小板膜上存在HLA-A和B位点的抗原。

单项选择题
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     Diana Jacobs thought her family had a workable plan to pay for college for her 21-year-old twin sons:

a combination of savings, income, scholarships, and a modest amount of borrowing. Then her husband

lost his job, and the plan fell apart.

     "I have two kids in college, and I want to say 'come home,' but at the same time I want to provide them

with a good education," says Jacobs.

     The Jacobs family did work out a solution: They asked and received more aid from the schools, and

each son increased his borrowing to the maximum amount through the federal loan (贷款) program. They

will each graduate with $20,000 of debt, but at least they will be able to finish school.

     With unemployment rising, financial aid administrators expect to hear more families like the Jacobs. More

students are applying for aid, and more families expect to need student loans. College administrators are

concerned that they will not have enough aid money to go around.

     At the same time, tuition (学费) continues to rise. A report from the National Center for Public Policy and

Higher Education found that college tuition and fees increased 439% from 1982 to 2007, while average family

income rose just 147%. Student borrowing has more than doubled in the last decade.

     "If we go on this way for another 25years, we won't have an affordable system of higher education," says

Patrick M. Callan, president of the center. "The middle class families have been financing it through debt. They

will send kids to college whatever it takes, even if that means a huge amount of debt."

     Financial aid administrators have been having a hard time as many companies decide that student loans are

not profitable enough and have stopped making them. The good news, however, is that federal loans account

for about three quarters of student borrowing, and the government says that money will flow uninterrupted.

1. According to Paragraph 1, why did the plan of Jacobs family fail?

A. The twins wasted too much money.

B. The father was out of work.

C. Their saving ran out.

D. The family fell apart.

2. How did the Jacobs manage to solve their problem?

A. They asked their kids to come home.

B. They borrowed $20,000 from the school.

C. They encouraged their twin sons to do part-time jobs.

D. They got help from the school and the federal government.

3. Financial aid administrators believe that _____.

A. more families will face the same problem as the Jacobs

B. the government will receive more letters of complaint

C. college tuition fees will double soon

D. America's unemployment will fall

4. Financial aid administrators believe that _____.

A. more families will face the same problem as the Jacobs

B. the government will receive more letters of complaint

C. college tuition fees will double soon

D. America's unemployment will fall

5. Financial aid administrators believe that _____.

A. more families will face the same problem as the Jacobs

B. the government will receive more letters of complaint

C. college tuition fees will double soon

D. America's unemployment will fall