大肠杆菌DNA聚合酶I的作用不包括() A.5'→3'外切酶活性 B.3'→5'外切

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问题:

大肠杆菌DNA聚合酶I的作用不包括()

A.5'→3'外切酶活性

B.3'→5'外切酶活性

C.5'→3'DNA聚合酶活性

D.3'→5'DNA聚合酶活性

考点:分子生物学DNA与染色体DNA与染色体题库
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封闭式基金与开放式基金的区别在于( )。

A.投资者的身份不同

B.期限和发行规模限制不同

C.基金份额的交易价格计算标准不同

D.投资策略不同

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右侧胸腔积液:结核性胸膜炎[病例摘要]男性,30岁,低热伴右侧胸痛一周患者一周前无明显诱因出现午后低热,体温37.5℃,夜间盗汗,伴右侧胸痛,深呼吸时明显,不放射,与活动无关,未到医院检查,自服止痛药,于3天前胸痛减轻,但胸闷加重伴气短,故来医院检查,发病来进食无变化,二便正常,睡眠稍差,体重无明显变化。既往体健,否认有结核病密切接触史,吸烟10年。查体:T37.4℃,P84次/分,R20次/分,Bp120/80mmHg,一般情况可,无皮诊,全身浅表淋巴结未触及,巩膜不黄,咽(-),颈软,气管稍左偏,颈静脉无怒张,甲状腺(-),右侧胸廓稍膨隆,右下肺语颤减弱,右下肺叩浊,呼吸音减弱至消失,心界向左移位,心右界叩不清,心率84次/分,律齐,无杂音,腹平软,无压痛,肝脾未及,下肢不肿。

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有一冒口的体积1950C.m3,其表面积为1000C.m2,则求冒口模数?

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Of all the employed workers in the United States, 12.5 million are part of a temporary workforce. The United States Bureau of Labor Statistics counts 9.2 percent of workers as those who have______(1) they term "alternative employment arrangements." The government predicts that temporary staffing agencies______(2) experience growth of 49 percent by 2010. If numbers increase at the rate ______ (3), these companies will add 1.9 million new jobs by 2010. That’’s more than any______(4) industry.Temporary workers were the first ones to be affected by the recent economic recession, but they are______(5) to be the first to regain positions as the economy picks up and companies work to rebuild. Employers use temporary workers as a resource because_______(6) offer flexibility and come at a low cost. Many temporaries are categorized as "independent contractors" instead of employees,______(7) allows the employer to avoid______(8) certain taxes. Because they are not required to offer benefits to temporary workers, companies can save a great deal of money by hiring temps. Usually, temporary workers can qualify_______(9) benefits if they work for a staffing company for a certain length of time. Most temps, however, do not continue with one company long______(10) to qualify for them because they regard the position as a step on the ladder to a______(11) position later.According to Richard Wahlquist, president of the American Staffing Association, 75_______(12) of temporary workers hope for transition out of the temporary staffing category______(13) a period of time. Wahlquist finds that temporary workers spend about 11 weeks on various assignments before their______(14) out of the temporary workforce. Many use temporary positions to gain experience and skills______(15) they move on to better jobs. Wahlquist says that the temp workforce as a whole turns______(16) 400 percent each year.Tom Dilworth, research director at the Employment Policies Institute, explains______(17) some workers like having temporary jobs______(18) it affords them a great deal of elasticity with time and everything. Some temps only have a limited______(19) of time to work and temp agencies can help coordinate jobs to fit their schedules. Other sometimes-employees use temporary jobs to get an______(20) to a company from the inside, to get a foot in the door of a certain business or career._______(21) others take temporary positions in hopes their employers will change them over to permanent positions eventually.Nearly all the industries in the United States use temporary workers.______(22) to Tim Costello, coordinator of the North American Alliance for Fair Employment, the growth of temporary labor threatens______(23) job security of permanent workers who fear replacement, as well as the temps who are more accustomed to turnover. He predicts that there will continue to______(24) a gradual shift from permanent employees to contingent staffing, and that such a_____(25) in workplace demographics will "lead to lower wages, poorer working conditions, and more instability."

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阿片受体阻断剂为

A.二氢埃托啡
B.罗通定
C.纳曲酮
D.芬太尼
E.哌替啶

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