人体最早的造血干细胞来源于() A.卵黄囊 B.肝脏 C.骨髓 D.脾脏 E.淋巴结

题型:单项选择题 B1型题

问题:

人体最早的造血干细胞来源于()

A.卵黄囊

B.肝脏

C.骨髓

D.脾脏

E.淋巴结

考点:临床医学检验技术(主管技师)临床血液学临床血液学题库
题型:单项选择题 B1型题

姻亲

题型:单项选择题 B1型题

关于下丘脑激素的调节,下列哪项是正确的()

A.5-羟色胺可促进LH-RH的分泌

B.多巴胺可刺激LH-RH的分泌

C.去甲肾上腺素可抑制LH-RH分泌

D.雌激素对丘脑下部产生正反馈也产生负反馈

E.Gn-RH对下丘脑可产生正反馈

题型:单项选择题 B1型题

Beijing: The United States and North Korea had their first ______ in four months here this afternoon as part of the ______ negotiations on how to end North Korea’s nuclear program, but diplomats played down prospects for______. James A. Kelly, assistant ______, and Kim Yong Ⅱ, North Korea’s deputy foreign minister, met ______ of formal discussions, ______ on direct dialogue that began after a stormy meeting ______ in which North Korea warned that it was moving quickly to ______ nuclear arms. The Bush administration had insisted ______ that it would only hold talks with North Korea ______ because, it argued, only ______ pressure would persuade North Korea to______. It got its way when North Korea dropped its insistence on ______ and agreed, after extensive efforts by China, to hold unusual simultaneous negotiations with ______,______,______ and ______ as well as the United States. Though Bush administration officials had not ______ talking privately with the North Koreans during______, the fact that Mr. Kelly and Mr. Kim met on the first day was seen as a sign of ______ by the American side.

题型:单项选择题 B1型题

下列选项中,可产生高T值的碱基对是()

A.G+C

B.A+T

C.A+C

D.A+G

E.T+C

题型:单项选择题 B1型题

差错控制采用的4种工作是();();();()。

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