问题 单项选择题

人类T细胞不具备的受体是( )

A.E受体
B.IgG Fc受体
C.C3b受体
D.DHA受体
E.IL-2受体

答案

参考答案:C

解析: T细胞的主要表面分子有:①T细胞抗原受体(TCR)是T细胞识别蛋白抗原的特异性受体,如E受体等;②CD3分子是T细胞识别抗原的主要识别单位,具有稳定TcR结构和传递活化信号的作用;③CD4和CD8分子是细胞与细胞之间相互作用的黏附分子;④CD28分子是主要的协同刺激分子;⑤CD2分子是细胞间黏附分子,也是信号传导分子,是T细胞活化的第二途径;⑥极迟活化VLA可与细胞外基质配体分子相结合,为T细胞活化提供协同刺激信号;⑦细胞因子受体;⑧CD44和CD45分子,CD44分子为一种归巢受体,CD45对各种活化途径有调节作用。

单项选择题
单项选择题

Many things make people think artists are weird—the odd hours, the nonconformity, the clove cigarettes. However, the weirdest may be this: artists’ only jobs are to explore emotions, and yet they choose to focus on the ones that feel lousy. This wasn’t always so. The earliest forms of art, like painting and music, are those best suited for expressing joy. But somewhere in the 19th century, more artists began seeing happiness as insipid, phony or, worst of all, boring. In the 20th century, classical music became more atonal, visual art more unsettling.

Sure, there have been exceptions, but it would not be a stretch to say that for the past century or so, serious art has been at war with happiness. In 1824, Beethoven completed his " Ode to Joy " . In 1962, novelist Anthony Burgess used it in A Clockwork Orange as the favorite music of his ultra-violent antihero.

You could argue that art became more skeptical of happiness because modem times have seen such misery. But the reason may actually be just the opposite: there is too much happiness in the world today.

In the West, before mass communication and literacy, the most powerful mass medium was the church, which reminded worshippers that their souls were in peril and that they would someday be meat for worms. Today the messages that the average Westerner is bombarded with are not religious but commercial, and relentlessly happy. Since these messages have an agenda—to pry our wallets from our pockets—they make the very idea of happiness seem bogus. " Celebrate! " commanded the ads for the arthritis drug Celebrex, before we found out it could increase the risk of heart attack.

What we forget—what our economy depends on us forgetting—is that happiness is more than pleasure without pain. The things that bring the greatest joy carry the greatest potential for loss and disappointment. Today, surrounded by promises of easy happiness, we need someone to tell us that it is OK not to be happy, that sadness makes happiness deeper. As the wine connoisseur movie Sideways tells us, it is the kiss of decay and mortality that makes grape juice into Pinot Noir. We need art to tell us, as religion once did, that you will die, that everything ends, and that happiness comes not in denying this but in living with it. It’s a message even more bitter than a clove cigarette, yet, somehow, is a breath of fresh air.

The word " Celebrex " in the advertisement()

A. misleads people into buying dangerous drugs

B. reminds people of a cheerful feeling

C. boasts of the effectiveness of a drug

D. comes from a religious term