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81.
随着3g通信技术的深度发展,3g产业链呈现出多维互动格局.运营商将在更多环节、更广泛区域内与更多主体形成复杂和敏感的法律关系,从而增大了运营商所承担的法律风险.运营商必须强化对3g产业链的控制、协调、整合,合理有效地防范3g运营的法律风险.  相似文献   
82.
为建立金黄色葡萄球菌5型荚膜多糖(CP5)纯化与偶联技术方法,获得具有免疫原性的CP5偶联抗原,采用高压破碎菌体的方法释放荚膜多糖,酶处理去除核酸和蛋白质,通过离子交换层析进一步纯化,得到纯化的CP5,并对其纯度和反应原性进行检测;采用己二酸二酰肼(ADH)间桥法制备CP5-牛血清白蛋白(CP5-BSA)偶联抗原,加佐剂免疫小鼠,进行抗体水平测定。结果表明,纯化的CP5纯度为675.1g/kg,经用免疫琼脂双扩散试验检测,纯化多糖仅与同型菌株抗血清发生沉淀反应,偶联抗原CP5-BSA可以刺激小鼠产生CP5免疫应答。此研究结果为奶牛乳房炎金黄色葡萄球菌亚单位疫苗的研制提供了试验依据。  相似文献   
83.
This article addresses the unsuccessful attempts to suppress free speech during the Korean War, and in particular explains the attempts to silence three reporters of alleged atrocities by United Nations forces. In the absence of carefully targeted legislation, the three individuals – Alan Winnington (a journalist), Monica Felton (a women's movement activist) and Jack Gaster (a solicitor) ‐ were threatened with or investigated for prosecution for treason or sedition, and Winnington was unable to renew his passport until 1968. Drawing heavily on archival sources (including MI5 files, which unusually fail to redact the identity of one of the lawyers who was reporting to Special Branch about Gaster's activities), the article explores the threat to civil liberties from the administrative as well as the legislative and the judicial power of the state. The article concludes by drawing contemporary parallels, and highlighting the continuing relevance of the writings of Winnington, Felton and Gaster.  相似文献   
84.
A new sildenafil analogue was detected during routine screening of dietary supplements suspected to be adulterated with an erectile dysfunction drug(s) using HPLC-DAD. The UV spectrum of this compound was highly similar to that of sildenafil and almost identical to that of desmethylpiperazinyl sildenafil. The analogue was purified by using semi-preparative HPLC and structurally elucidated by performing mass spectrometric and NMR spectroscopic experiments. The spectral data revealed that this sildenafil analogue bears an n-propoxy group instead of an ethoxy group and possesses no methylpiperazinyl moiety. The isolated compound, structure of which was further confirmed by spectral comparison with synthetic one, was thus named as desmethylpiperazinyl propoxysildenafil.  相似文献   
85.
The Time Machine of H. G. Wells stands as one of the foundational works of science fiction. It is a true product of its time, a reflection of the fast pace of technological development and social change that makes a romance of the ideology of advancement for its own sake. But between the lines of its “adventure” plot, we find evidence of another, more complex story being told. Wells's work is plagued by ambivalence about the outcome of social and scientific progress—the selfsame progress that gave birth to the time machine in the first place. The Time Machine, in short, is preoccupied by an anxiety about a catastrophe just around the corner, not one born of global war or political turmoil but rather of the absence of turmoil, of need, of struggle. The idea and possibility of fiction itself becomes entangled in this problem of the everyday catastrophe, as it nearly suffocates under the conditions of the utopian society which it creates.  相似文献   
86.
目的研究显现、提取遗留在人民币上潜在指印的方法。方法采用荧光试剂罗丹明6G对人民币进行染色处理,以LED多波段光源输出的波长为520nm的绿光照射检材,透过580nm的带通型干涉滤光镜观察指印的显现效果,并拍照提取。结果获得亮纹线暗背景的指印图像,指印纹线清晰,反差良好,特征丰富,具备良好的检验鉴定条件。结论 LED多波段光源输出的波长为520nm的绿光与罗丹明6G染色指印的吸收特性吻合,是显现、提取遗留在人民币上潜在指印的良好光源。  相似文献   
87.
In this paper, we test the argument that the sizeable reduction in aggregate aid levels in the 1990s was due to the end of the Cold War. We test two different models using a dynamic econometric specification on a panel of 17 donor countries, spanning the years 1970–97. We find aid to be positively related to military expenditures in the former Eastern Bloc during the Cold War, but not in the 1990s, suggesting that the reductions in aid disbursements are driven by the disappearance of an important motive for aid. We also study the effect on aid allocation, but here we do not find any robust effects of the end of the Cold War.  相似文献   
88.
The European Union has been trying to achieve its long-term goals through partnerships and cooperation with other like-minded global actors. Africa (through its regional institutional body, the African Union) has been the first and only multilateral entity with which the EU has forged a long-term partnership. Despite its rhetorical language, the Africa--EU Strategic Partnership is unlikely to upgrade the political and economic interaction between the two partners. In the past few years, serious rifts have grown between the EU and its African counterparts concerning trade agreements and development policies. Moreover, new actors have made significant inroads in Africa, providing an alternative to its long-standing dependence on Europe.  相似文献   
89.
将猪生殖与呼吸综合征病毒(PRRSV)CH-1a株GP5蛋白基因信号肽部分删除后克隆于pGEX-6p-1载体上,并在大肠埃希氏菌中进行表达。经SDS-PAGE电泳分析发现,融合表达的rtGP5蛋白约42 ku,将融合蛋白rtGP5用PRRSV阳性血清进行Western-blotting分析,证实所表达的融合蛋白能被其特异性识别。收获融合表达产物rtGP5,按50μg/只的剂量与等量弗氏佐剂乳化,经腹腔免疫BALB/c小鼠3次后,取脾细胞与SP2/0骨髓瘤细胞进行融合,分别以融合蛋白rtGP5和GST蛋白为抗原,通过间接ELISA方法对融合细胞的上清液进行检测,筛选阳性克隆,结果得到了15株能稳定分泌抗rtGP5蛋白抗体的阳性细胞克隆株。经间接免疫荧光检测发现,获得的15株单克隆抗体都能与PRRSV感染细胞产生特异性荧光。15株单克隆抗体亚型鉴定结果显示均为IgG1型,且轻链均为κ链。  相似文献   
90.
细胞周期蛋白依赖激酶5(cyclin-dependent kinase 5,CDK5)是CDK家族中一类不直接调控细胞周期的蛋白。CDK5通过靶蛋白的磷酸化在神经细胞的发育、修复及退行性变等方面发挥着不可替代的作用。脑损伤是指暴力作用于头部造成的脑组织器质性损伤,由于损伤发生后机体启动应激及修复机制,脑组织中变化的多种蛋白及酶类物质可作为损伤时间判定的指标。本文就CDK5的分布、活性机制、生理作用及其脑损伤研究与其作为脑损伤标志物可能性的研究进展进行综述。  相似文献   
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