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问题 单项选择题 A1/A2型题

原发性肝细胞癌最敏感的肿瘤标志是（）。

A.肝脏B超

B.肝CT

C.AFP

D.AP

E.γ-GT

答案

参考答案：C

解析：AFP是原发性肝细胞肝癌的最灵敏、最特异的肿瘤标志。除AFP阴性肝癌外，若AFP小于20μg／L，原发性肝癌基本不可能；AFP在100～300μg／L之间者必须进行随访，密切观察AFP的动态变化，注意可能的小肝癌AFP在350～500μg／L，或含量明显增高者，必须参考其他检查，应高度警惕原发性肝癌的可能；AFP为500～1000μg／L，且含量在短期内不断升高，原发性肝癌可能性很大，建议活检；AFP大于1000μg／L者，甚至在近期内AFP含量迅速升高，则原发性肝癌诊断基本可确定。

选择题

在许多生物实验中都需要细胞作实验材料。下列处于生活状态的细胞有

①浸在0.3g/mL的蔗糖溶液中的洋葱表皮细胞 ②解离后的洋葱根尖分生区细胞 ③放在9%的NaCl溶液中的人的红细胞 ④放在清水中的黑藻叶片细胞[ ]

A．①③

B．①④

C．②④

D．②③
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问答题

Passage 1 Changes in educational approaches, beliefs and practices come faster today than most teachers, parents and children can begin to assimilate. Speedy results are seen as politically necessary. When new approaches are not successful immediately, they are abandoned in favor of even newer ones. // In repeated and accelerated cycles of change it is the children who suffer. Hurried through the school day and through the grade levels, they are left with little time to reflect on what they are learning or where their lives are beaded. Our schools tend to be fact factories, cramming more into every minute of every hour of every day. There always seems to be more curriculum to cover and more tests to take—but never any time added to the day. Children and teachers are left gasping for air. // We must stop hurrying children and give them adequate time for learning. We need more clarity, more planning and less impulsive implementation of "the latest best thing." There is an urgent need in our schools for increased accountability and more focused attention on basic skills. But that very urgency must not lead us to rush. The pace of change must be reasonable and related to the right pace for children’s learning. // True learning requires time: time to wonder, time to share and time to pay attention to what is most important. To hurry through classes and a predetermined timetable of achievements is contrary to the nature of children and will do irreparable damage to their minds and souls. School comes from the Greek word scholé which translates literally as "leisure." Consider how far we’ve moved from our educational roots! //
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