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问题 单项选择题

可刺激肥大细胞脱颗粒释放生物活性介质的补体成分是（）

A.C1q

B.C3b

C.C5a

D.C4b

E.C2a

答案

参考答案：C

解析：C3a、C4a、C5a作为配体与肥大细胞、嗜碱性粒细胞、中性粒细胞、单核巨噬细胞和内皮细胞表面相应受体结合，激发细胞脱颗粒，释放组胺之类的血管活性介质，从而增加血管通透性并刺激内脏平滑肌收缩，称过敏毒素。C5a还是一种趋化因子。

单项选择题

患者，男，20岁。左踝部疼痛，行走时加重，喜温热，舌苔白，脉弦紧。治疗应首选

A．申脉、照海、昆仑、丘墟

B．悬钟、照海、丘墟、三阴交

C．太溪、昆仑、阳陵泉、解溪

D．太冲、太溪、照海、悬钟

E．昆仑、悬钟、阴陵泉、申脉
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单项选择题

The history of African—Americans during the past 400 years is traditionally narrated (1) an ongoing struggle against (2) and indifference on the part of the American mainstream, and a struggle (3) as an upward movement is (4) toward ever more justice and opportunity.

Technology in and of (5) is not at fault; it’s much too simple to say that gunpowder or agricultural machinery or fiber optics (6) been the enemy of an (7) group of people. A certain machine is put (8) work in a certain way—the purpose (9) which it was designed. The people who design the machines are not intent on unleashing chaos; they are usually trying to (10) a task more quickly, cleanly, or cheaply, (11) the imperative of innovation and efficiency that has ruled Western civilization (12) the Renaissance.

Mastery of technology is second only (13) money as the true measure of accomplishment in this country, and it is very likely that by (14) this under-representation in the technological realm, and by not questioning and examining the folkways that have (15) it, blacks are allowing. (16) to be kept out of the mainstream once again. This time, however, they will be (17) from the greatest cash engine of the twenty-first century. Inner-city blacks in particular are in danger, and the beautiful suburbs (18) ring the decay of Hartford, shed the past and learn to exist without contemplating or encountering the tragedy of the inner city.

And blacks must change as well. The ways that (19) their ancestors through captivity and coming to freedom have begun to loose their utility. If blacks (20) to survive as full participants in this society, they have to understand what works now.

8（）

A.for

B.off

C.on

D.at
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