全同胞交配的近交系数上升率四代以后恒定为()。A、28% B、17% C、20%

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问题:

全同胞交配的近交系数上升率四代以后恒定为()。

A、28%

B、17%

C、20%

D、19%

考点:生物学实验动物学实验动物学题库
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患者,男性,32岁,6天前感冒后出现左下后牙区胀痛,进食、吞咽时加重。昨日起出现局部自发性跳痛,开口受限,低热,头痛。检查可见:左下颌角区颊部稍肿胀,无压痛,开口度两指,左下第三磨牙近中阻生牙龈红肿充血,挤压可见远中盲袋内少量脓液溢出,颊侧前庭沟丰满、充血,压痛明显,叩诊(-),无松动,咽侧壁稍充血,无压痛。

如患者出现重度开口受限,以下颌角为中心的肿胀,皮肤潮红、压痛,此时应怀疑存在()

A.颞下间隙感染

B.颞间隙感染

C.下颌下间隙感染

D.翼颌间隙感染

E.咬肌间隙感染

题型:单项选择题

物体所含物质的多少叫做物体的______,在国际单位制中,质量的基本单位是______.

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热水管网和热力站试运行有哪些规定?

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Few scientific fields are as full of risk as that of research into human intelligence. The two questions that (1) over and over again are "is it a result of nature or nurture" and "does race make a difference"

Making (2) comments about the second question can be a (3) move, as James Watson, a co-discoverer of DNA structure, recently found. He suggested that he was " (4) about the prospect of Africa" (5) "all our social policies are based on the fact that their intelligence is the same as ours (white people) (6) all the testing says not really". Such (7) by Dr. Watson are not merely (8) , they are scientifically weird. If the term (9) has any useful scientific meaning, then Africa, the continent where modern humanity began, is most racially diverse. The resulting (10) among the public forced Dr. Watson to leave his laboratory.

(11) , the study of the first question (12) between intelligence and genetics— has some wiser practitioners. One of them, Terrie Moffitt, of King’s College, has just (13) a project judging the relative importance of nature and nurture. Dr. Moffitt’s team (14) the effect on intelligence of breastfeeding, but in a genetic context. Previous studies have shown that breastfed children are more intelligent, (15) about six IQ points, than those given baby formulas.

The team, however, (16) the involvement of a gene called FADS2, which comes in two varieties, known as C and G. The researchers (17) if these two varieties interacted differently with breast milk. (18) on data from two groups of people, they found that the intelligence increase associated with breastfeeding only happened to people having (19) at least one copy of the C variety. The effect did not. (20) on the social classes or IQs of the parents.

10()

A.finding

B.uproar

C.complexity

D.puzzlement

题型:单项选择题

停止预聚物输送泵时,应将泵速降至10%,然后()。

A、在自动控制下停止

B、在串级控制下停止

C、在手动控制下停止

D、只要停止就行

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