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问题 单项选择题

从中药甲醇提取物中提取含糖较多的苷常用

A．氯仿＋丙酮

B．正丁醇

C．无水乙醇

D．稀乙醇

E．乙酸乙酯

答案

参考答案：B

解析：正丁醇对多糖苷的溶解度高，而且能够与水分层。

单项选择题

下列针对脾破裂的处理，错误的是

A．破裂严重时，可行脾切除

B．治疗原则是紧急手术

C．待失血性休克好转后再行手术

D．可收集腹腔内血液行自身输血
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单项选择题

In the following essay, each blank has four choices. Choose the best answer and write down on the answer sheet.

It is more and more usual that users of Information Retrieval (IR) systems must face up to response of hundreds or thousands of (1) documents. A significant proportion of them are moreover (2) or redundant. This is a straight consequence of two well - known facts: the incessant growing of documental databases and the lack of ability of most users to define (3) information needs. In such a framework, further effective retrieval techniques are only part of the solution. Interfaces with alternative ways for organizing and (4) the results returned by a (5) would be of great utility assisting users to find relevant documents. Document clustering may play a central role as an effective technique for organizing query results.

2（）

A．relevant

B．irrelevant

C．complicated

D．complex
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