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【多选题】
下列关于喹诺酮类药物构效关系描述正确的是A.
吡酮酸环是抗菌作用必需的基本结构
B.
2位上引人取代基活性增加
C.
3位羧基和4位酮基是抗菌活性的必需基团
D.
在6位引人氟原子抗菌活性增加
E.
在7位上引人哌嗪基使活性增加
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皮皮学刷刷变学霸
举一反三
【单选题】Troubles ________ in the city as the municipal government failed to control the inflation effectively.
A.
fouled up
B.
messed up
C.
flared up
D.
slacked up
【单选题】The city government promises to _________the problem of unemployment in real earnest.
A.
postpone
B.
tackle
C.
compose
D.
anticipate
【简答题】The government __________ regulations that put this old city under protection.
【单选题】The city dwellers called for the government to __________more responsibilities for the welfare of the homeless.
A.
take on
B.
take apart
C.
take place
D.
take effect
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