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1.
采用体外成熟的牛卵母细胞 ,经 5 μmol/LIonomycin 5min和 2mmol/L 6 DMAP 5 μg/mLCCB 4h激活 ,分别在TALP M 199(TM ,1∶2 )、BMOC M 199(BM ,1∶2 )和CR1aa培养液内培养 ,2 4h和 3 6h各组卵母细胞的卵裂率分别为5 6.4%、5 5 .6%、5 3 .6%和 72 .0 %、75 .9%、79.0 % ,无显著差异 (P >0 .0 5 ) ;培养 8d后囊胚发育率分别为 18.2 %、2 1.4%和 2 9.3 % ,CR1aa内培养孤雌生殖胚的囊胚发育率显著高于TM (P <0 .0 1)。皮肤成纤维细胞构建的重组胚经同法激活后 ,分别在TM、BM和CR1aa内培养 ,2 4h和 3 6hBM和CR1aa内重组胚的卵裂率显著高于TM (4 9.7%、49.8%比 2 0 .5 % ;74.1%、73 .2 %比 5 0 .0 % ) (P <0 .0 1) ;虽然培养 8d后各组胚胎的囊胚发育率无显著差异 ,但CR1aa内重组胚的囊胚发育率稍高 (12 .3 %比 9.8%、11.5 % )。结果表明 ,CR1aa更适合孤雌生殖和体细胞核移植胚胎的体外培养。  相似文献   
2.
FSH对仔猪睾丸支持细胞增殖和GDNF表达的调节   总被引:2,自引:0,他引:2  
以原代培养的仔猪睾丸支持细胞(SC)为试验模型,研究了FSH对SC胶质细胞源性神经营养因子(GDNF)表达及其增殖的影响。结果显示,外源性添加FSH可促进GDNF蛋白表达,而且这种促进作用具有浓度和时间依赖关系,GDNF蛋白水平随着FSH浓度的增加而升高,当FSH浓度为50 ng/mL时,GDNF水平达到最高,然后逐渐降低;FSH(50 ng/mL)作用30 min,可显著促进GDNF蛋白的表达(P<0.05),当FSH作用1 h时,GDNF蛋白水平达到最高,随后逐渐降低。FSH可以时间-剂量依赖性促进SC增殖细胞核抗原(PCNA)的表达,FSH(50 ng/mL)作用30 min时,PCNA的表达显著增加(P<0.05),作用1 h达极显著水平(P<0.01),至2 h时,PCNA蛋白的表达水平达到最高,随后逐渐降低。提示,FSH可在体外条件下通过刺激SC表达GDNF进而促进其增殖。  相似文献   
3.
In 2017, significant media and political interest was sparked by the UK decision to leave Euratom, the European Atomic Energy Community. While such interest in nuclear matters has to be welcomed, the apparent lack of knowledge displayed in the regulatory governance of the UK nuclear industry is disquieting. This article therefore offers an overview of the publicly funded UK nuclear industry and its regulatory governance including its links with European and global nuclear agencies to inform the debate and to identify critical issues in need of resolution.  相似文献   
4.
This essay considers how the state can be used successfully to initiate and support an energy shift from nuclear energy to renewable energy, as demonstrated by Germany’s Renewable Energy Act from 2000 and its previous Electricity Feed-in-Law (1991). As a result of these nationwide policies, Germany has reduced levels of greenhouse gas emissions, has a higher level of both energy security and employment in the renewable energy industry than the US. Germany is a global leader in this industry and provides a model for other nations in this regard.  相似文献   
5.
Edward Kwon 《亚洲事务》2018,49(3):402-432
This paper analyzes the policy remedies for dealing with North Korea's nuclear weapons and missile programs. After six nuclear tests and three recent successful ICBM tests, North Korea is close to miniaturizing nuclear warheads and establishing a reliable delivery system, thus achieving a much-feared nuclear weapons capability. In defiance of the extraordinarily tough U.N. Security Council resolutions, Pyongyang persists in developing nuclear weapons. North Korea's nuclear weapons program already has exceeded the strategic patience, of the U.S.-ROK alliance. Harsher policy options to deal with the DPRK nuclear weapons are imperative. Several drastic options, including severe sanctions, preventive bombing, nuclear armament of South Korea, are evaluated in the final round of engagement policy on guaranteeing nonaggression and a peace agreement with Pyongyang.  相似文献   
6.
Recent studies on European Union (EU) Enlargement have emphasised the importance of usages of ‘Europe’ by domestic actors as a necessary condition for the EU to have an impact on domestic politics. We study the usages of Europe in the critical case of Turkey’s nuclear energy policy. We analyse the narratives and actions of domestic actors in Turkey to identify if they use ‘Europe’ (the EU and the idea of Europe). We reach the counter-intuitive finding of usages by both state and non-state actors, which illustrates that usages of Europe can persist despite enlargement stasis in candidate states.  相似文献   
7.
ABSTRACT

How do actors come to contest previously uncontested background ideas? This is a difficult question to ask. On the one hand, deep backgrounds seem to be too foundational for actors to transform. Their political efficacy appears to end where ideas constitute their efficacy in the first place. On the other hand, ideas must not be reified. Even deeply taken-for-granted ideas do not always stay the same, and agents have a lot to do with these changes. In order to answer this question, we draw from social theory and rhetorical studies. We conceptualize the deep background as nomos, and the more easily accessible background as endoxa. We then proceed to identify three sets of conditions that make nomic change possible. These relate to opportunity, message, and messenger. Nomic change becomes possible when the need for something new has become widely established and a supply of new nomic ideas is easily available (opportunity); new nomic ideas are ‘smuggled’ into more orthodox and widely resonating arguments (message) as well as rhetorical encounters in which these arguments are made; and advocates are widely recognized as interlocutors (messenger). A plausibility probe of nomic contestation about nuclear governance provides evidence for this framework.  相似文献   
8.
沈秋欢 《东南亚》2009,(3):18-22
冷战结束以来,特别是近十年面对印度和朝鲜发展核力量的努力,美国采取了完全不同的核政策。美国对印度持友善甚至支持的态度,而对朝鲜采取对抗性政策。本文试从温特的身份建构主义并结合语言行为的角度分析,揭示美国形成不同核政策的原因——美国对两国构建起截然不同的身份。冷战后,美印互动促使美国对印度在冷战时期构建起的非敌非友身份向准盟友方向转化,而美朝的互动强化了美国在冷战时期就已经构建起的敌人身份认同。  相似文献   
9.
目的:观察中药复方消核冲剂对实验性乳腺增生大鼠血清性激素水平和增生乳腺组织中增殖细胞核抗原(PCNA)表达的影响,探讨该药物治疗乳腺增生病的可能机制.方法:Wistar雌性大鼠60只,随机分为空白对照组(对照组)、模型对照组(模型组)、消核冲剂组(中药组)、他莫昔芬组(西药组),每组15只.肌注苯甲酸雌二醇(E2)、黄体酮复制大鼠乳腺增生模型.模型复制后灌服药物,化学发光免疫法测定血清性激素水平,免疫组化法观察乳腺组织PCNA的表达.结果:中药组和西药组血清E2、孕酮(P)水平均低于模型组,差异有显著性;PCNA阳性细胞数目和阳性细胞面积中药组和西药组均明显减少.中药组各项指标的改变与西药组相比均无明显差异.结论:中药复方消核冲剂对乳腺增生大鼠血清性激素水平具有调节作用,同时也能够下调PCNA阳性表达.  相似文献   
10.
1991年12月9日《欧洲联盟条约》签署后,欧洲联盟国家在追求经济一体化的同时,也在追求政治一体化,即欧洲联盟国家应以国家联盟共同体的方式,用一种声音说话。由于欧盟成员国间政治经济发展的不平衡以及在对外关系中的各自特点和差异,欧盟在对外政策上要完全用一个声音说话,还需要一个较为漫长的过程,也会受到成员国各种因素的制约。欧盟对朝鲜半岛政策从奉行接触到积极介入以及其中的起伏变化,多少能够看出欧盟在对外政策方面的相对模糊与迟缓。  相似文献   
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