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蛋白O-连接岩藻糖基转移酶1 (Pofut1)基因缺失可导致Notch分子无法与配体结合并启动信号传递. 为研究Pofut1基因对哺乳动物胚胎干细胞(ESC)向神经分化的影响,利用Pofut1基因敲除的胚胎干细胞与野生型胚胎干细胞,经体外培养诱导拟胚体(EB)分化为神经细胞,计数分化为神经细胞的比例,采用细胞免疫组化染色和real-time PCR等方法,分析神经细胞特异性标志分子的表达. 结果显示,Pofut1基因缺失后,对EBC生长没有明显影响,分化过程中形成的拟胚体数量明显增多,分化的神经样细胞以及神经标志物分子的表达也明显多于对照组;Notch信号缺失对小鼠胚胎干细胞生长无明显影响,但可以促进ES细胞向神经细胞分化. 相似文献
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穆玉姣 《微生物学免疫学进展》2008,36(3)
整合子和金属β-内酰胺酶(MBL)使铜绿假单胞菌的耐药机制更加复杂,给临床的抗感染治疗带来了较大的困难。I类整合子(IntI)的结构与其在铜绿假单胞菌四类金属酶的耐药基因中的传播作用是临床关注的问题之一。 相似文献
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XUSHIXIONG 《Cell research》1993,3(1):93-101
The pattern of change of the microtubule cytoskeleton of the root-tip cells of rice during mitosis was studied using immunofluorescence technic and confocal laser scanning microscopy. All the major stages of ceil division including preprophase, prophase, metaphase, anaphase and telophase were observed. The most significant finding was that in the preprophase cells microtubules radiating from the nuclear surface to the cortex were frequently seen. During development these microtubules became closely associated with the preprophase band and prophase spindie indicating that the microtubules radiating from the nuclear surface, the preprophase band and the prophazc spindle were structurally and functionally closely related to each other. Granule-like anchorage sites for the radiating microtubules at the muclear surface were often seen and the possibility that these gramle-like anchorage sites might represent the microtubule organizing centres was discussed. 相似文献
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井冈山自然保护区是中国一颗璀璨的绿色明珠,在当今地球上同纬度多为沙漠干旱地区的事实面前,这里是一块难得的绿洲。它保存了第三纪以来发育的常绿阔叶林,至今还保留了许多诸如资源冷杉等侏罗纪古老的成分:还有许多见证1亿年前与北美洲联系的榧树、栲类、木兰类等成分。在漫长的历史长河中,井冈山不仅发育演化了丰富的生物多样性,而且产生了28种之多的新物种,诸如井冈山杜鹃、背绒杜鹃、伏毛 相似文献
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Zhang Jintun 《生物数学学报》1996,(4)
IIntroductionSuccessionstudyIsaspeclalfleldInvegetationecology(Greig—Smith1983).ItreferstocummulatlvechangeInvegetationovertime.Florl幻IcgradientsIndicativeofsuccessionaltrendsmayemergefromconventionalordinationIfextrinsic!nformatlonallowsthemtobel-dentlfledassuch.Inthespedalcaseofforestvegetation,forInstance,Informationonthesize—classesoftreespedespresentmaypermitsuccessionalgradientslobeldentlfleddirectly(Goff1968,Carleton&Maycock1978).Fewauthors,however,haveattempted… 相似文献
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这里曾谱写过肃慎渔猎生活的历史,流传着海东青捕拿天鹅的故事,并与一个让亿万中国人熟悉的词汇"北大荒"紧密相连;这里还发现了中国丹顶鹤的第三大繁殖群以及其它珍禽。这里就是兴凯湖,位于北国边境上的一颗绿色明珠。本期自然将引领您走入这片充满光荣与梦想的传奇土地…… 相似文献
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