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【多选题】
How do retroviruses proliferate in host cells?
A.
Like retrotransposons, retroviruses use the enzyme reverse transcriptase to convert RNA into DN The enzyme is encoded by the retroviral genome, and a few molecules of the enzyme are packaged along with the RNA genome in each virus particle. When the single-stranded RNA genome of the retrovirus enters a cell, the reverse transcriptase brought in with it makes a complementary DNA strand to form a DNA/RNA hybrid double helix.
B.
The RNA strand is removed, and the reverse transcriptase (which can use either DNA or RNA as a template) now synthesizes a complementary DNA strand to produce a DNA double helix. This DNA is then inserted, or integrated, into a randomly selected site in the host genome by a virally encoded integrase enzyme. In this integrated state, the virus is latent: each time the host cell divides, it passes on a copy of the integrated viral genome, which is known as a provirus, to its progeny cells.
C.
The next step in the replication of a retrovirus—which can take place long after its integration into the host genome—is the copying of the integrated viral DNA into RNA by a host-cell RNA polymerase, which produces large numbers of single-stranded RNAs identical to the original infecting genome.
D.
These viral RNAs are then translated by the host-cell ribosomes to produce the viral shell proteins, the envelope proteins, and reverse transcriptase—all of which are assembled with the RNA genome into new virus particles.
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【单选题】在交货期内,如果存货需求量增加或供应商交货时间延迟,就可能发生缺货。为此,企业应保持的最佳保险储备量是( )。
A.
使保险储备的订货成本与持有成本之和最低的存货量
B.
使缺货损失和保险储备的持有成本之和最低的存货量
C.
使保险储备的持有成本最低的存货量
D.
使缺货损失最低的存货量
【单选题】开展健康教育的目的不在于
A.
帮助人们树立健康意识
B.
帮助病人树立信心,配合治疗
C.
指导病人增强体质促进康复
D.
让病人懂得疾病知识,以便自我治疗
E.
进行保健护理操作示范,使病人学会正确操作
【单选题】女,38岁。于高处取物时不慎摔下,呈骑跨式,伤及外阴部位,疼痛难忍,出现外阴血肿最易发生的部位是( )
A.
大阴唇
B.
小阴唇
C.
阴阜
D.
阴蒂
E.
会阴部
【判断题】亚投行于2016年1月16日在北京开业,成为全球首个由中国倡议设立的多边金融机构
A.
正确
B.
错误
【单选题】. 女, 38 岁,于高处取 物时不慎摔下,呈骑跨式,伤及外阴部位,疼痛难忍。 外阴血肿最易发生的部位在
A.
小阴唇
B.
大阴唇
C.
阴阜
D.
阴蒂
E.
处女膜
【单选题】开展健康教育的目的不在于
A.
帮助人们树立健康意识
B.
帮助病人树立信心,配合治疗
C.
指导病人增强体质促进康复
D.
让病人懂得医疗知识并自我治疗
E.
进行保健护理操作示范,使病人学会正确操作
【单选题】亚洲基础设施投资银行于2016年1月16日在北京宣告开业,引起海内外舆论的广泛关注。亚投行的设立( )
A.
旨在为亚洲国家的基础设施  建设提供资金支持
B.
使美欧的盟友关系飘忽不定
C.
推动世界政治格局变化
D.
导致美国经济霸主地位丧失
【单选题】张某,女,45岁,发热、咳嗽,右侧胸痛,病人自诉采取右侧卧位休息时,胸部疼痛减轻,呼吸稍通畅。此时卧位性质属于
A.
主动卧位
B.
被动卧位
C.
被迫卧位
D.
习惯卧位
E.
特异卧位
【单选题】女,38岁,于高处取物时不慎摔下,呈骑跨式,伤及外阴部位,疼痛难忍,出现外阴血肿最易发生的部位是
A.
大阴唇
B.
小阴唇
C.
阴蒂部
D.
会阴部
E.
阴阜
【单选题】According to this passage,
A.
brokers usually perform. the same kinds of services to their customers.
B.
brokers have little contact with each other.
C.
open competition tends to result in a common price for similar transactions at any given moment.
D.
changes in the pressure of available supplies of funds upon market tends to maintain a common price for similar transactions.
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