问题 单项选择题

关于移植物抗宿主反应,说法错误的是()

A.是移植物中免疫细胞对宿主成分发生免疫应答

B.是骨髓移植的主要障碍

C.是受者对移植物产生的排斥反应

D.是移植排斥的一种类型

E.由此引起的疾病称为移植物抗宿主疾病

答案

参考答案:C

解析:移植物抗宿主反应是机体处于免疫缺陷状态进行免疫重建后的一种免疫反应,一般发生在骨髓移植时。由于宿主免疫功能低下,移植物中的免疫活性细胞针对宿主的移植抗原发生免疫应答,所以是骨髓移植的主要障碍。它属于移植排斥反应的一种类型,由此引起的疾病称移植物抗宿主疾病。

填空题
填空题

President Bush arrived in Washington and forged ahead with an ambitious agenda- (1) tax cuts, vast changes in federal social programs, expansions of executive power and (2) broad remaking of energy and education policies.
Claiming a mandate by simply declaring (3) existence, his early successes dazzled his critics. With guru Karl Rove directing the (4) , Bush won a stunning series of political victories.
He muscled his agenda through (5) friendly Congress, and gained seats for his party in the 2002 midterm elections. (6) biggest triumph came in 2004, when he won a second term despite a (7) unpopular war.
The "permanent" Republican majority he and Rove envisioned even seemed attainable (8) Bush plunged himself into his most ambitious legislative effort yet: a partial privatization (9) Social Security.
But the president who boasted about "political capital" in the heady (10) after his re-election now faces the worst of political fates as he enters (11) final year in office: borderline irrelevance.
The president’s second term has (12) defined by legislative paralysis, marked by record-low approval ratings, presidential candidates who are (13) from his shadow, and a lingering war that’s sapping his remaining reservoirs of (14) .
As he enters his final year in office with the war continuing, Republican (15) for president bolting from his shadow, and his party back in the minority (16) Congress, he is politically weakened, an early entry into lame-duck status.
And the (17) Washington atmosphere he hoped to cure is just as nasty as it was (18) he came to office seven years ago.
"lie’s left our political institutions much (19) troubled than they were before," said Thomas E. Mann, a senior fellow at (20) Brookings Institution, a Washington-based think tank. "He didn’t create the ideological polarization, but he magnified it. \