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31.
摘要:目的 建立神经内分泌性前列腺癌( neuroendocrine prostate cancer,NEPC) 细胞模型和动物模型,探讨单胺氧化酶 A( monoamine oxidase A,MAOA)在前列腺癌神经内分泌分化( neuroendocrine transdifferentiation,NED) 中的作用及机制。 方法 选取人前列腺癌细胞系 C4-2,通过恩杂鲁胺( enzalutamide,ENZ)长期诱导获得 NEPC 细胞模型;通过酶活性实验、Real-time PCR 和 Western blot 技术检测 NED 过程中 MAOA 的水平变化;使用 MAOA 抑制剂氯吉灵( clorgyline,CLG)检测 MAOA 对神经内分泌标志物的影响并探讨其潜在机制;建立前列腺癌异种移植模型,体内实验验证 MAOA 与 NED 之间的相关性。 结果 ENZ 可作为诱导 NEPC 模型的方法;在 ENZ 引起的 NED 过程中,MAOA 的表达和活性增加;抑制 MAOA 的活性可以延缓 NED 的发生,这可能是 MAOA 通过抑制缺氧信号实现的。结论 MAOA 是促进 NED 和维持神经内分泌细胞特性的关键靶点,MAOA 抑制剂 CLG 可以延缓 NEPC 发生,可能作为前列腺癌患者的潜在治疗药物。  相似文献   
32.
摘要:猕猴是非常重要且珍贵的实验动物。 不处死猕猴为前提,以反复多次对猕猴进行全结肠肠道检查及研究为。目的,建立猕猴全结肠内镜检查前的肠道准备方法尤为重要。 本研究补充此方法目前尚无报道的空白。 30 只猕猴,结肠镜检查前 3 h 分多次予以芒硝溶液管喂。 通过肠镜观察肠道清洁情况,其中 3 只猕猴肠道准备为Ⅲ 级,其余猕猴肠道准备均为Ⅰ ~ Ⅱ 级。 所有猕猴在洗肠过程中,无严重脱水、休克、死亡等并发症发生,肠道准备为Ⅰ ~ Ⅱ级猕猴顺利完成全结肠内镜检查。  相似文献   
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Tangible augmented reality (TAR) technology opens a novel realm which integrates the computer-generated elements into the real word. Its applications into design education have been explored with a limi-tation to this entire area. TAR offers an innovative learning space by merging digital learning materials into the format of media with tools or objects which are direct parts of the physical space. It is therefore conceived that such combination opens new perspectives in teaching and learning. This paper presented and evaluated one TAR system to improve the pedagogical effectiveness of experiential and collaborative learning process in urban design education. The results from the experiments were analyzed under a previously developed theoretical framework, which show that TAR can enhance the design activities in some collaborative work.  相似文献   
35.
Inspired by the property diagrams in thermodynamics,which distinctly reflect the performance and characteristics of thermodynamic cycles,we establish a state equation for heat motion and introduce a two-dimension property diagram,T-q diagram,in heat transfer to analyze and optimize the performance of heat exchangers,where heat flow is a state parameter for heat motion.According to the property diagram,it is convenient to obtain the influences of heat exchanger area,heat capacity rate and flow arrangement on the heat transfer performance during the analysis of heat exchangers and their networks.For instance,when analyzing the heat exchanger network in a district heating system,it is obvious to find that:if both the heat demand and the indoor air temperature in each branch of the network are the same,the total area of heat exchangers,the flow rate of water and the return water temperature in each branch are all the same;if the indoor air temperatures in different branches are different,the temperatures of the waters after flowing through different branches are different,which means that the mixing process of return waters with the same temperature is not an essential requirement to realize the best performance of district heating systems.  相似文献   
36.
针对产品设计过程中,分散异构知识融合不足导致知识检索准确性不高、知识重用效率低等问题,提出一种知识融合模型.利用知识需求模型传递知识需求信息,采用知识元对各类异构知识进行统一表示,通过概念本体对语义概念进行有序组织,与知识元之间形成映射关系.通过语义距离计算获取候选知识元集,并采用基于贝叶斯和遗传算法的知识融合方法将分散的关联知识元融合成知识单元,实现知识重用.以覆盖件模具结构设计为案例验证了所提出方法的可行性和有效性.  相似文献   
37.
山体滑坡给人们的生命财产带来巨大损失,提出了基于DTR技术的山体滑坡检测监视系统;当同轴电缆发生变形时,它的特性阻抗将发生变化,向同轴电缆发送测试电磁脉冲,当测试脉冲遇到电缆的特性阻抗发生变化,就会产生电磁波,通过测量反射电磁波的传输时间就知道发生阻抗变化的位置,即山体内部结构变化的地方,及时掌握山体的运动情况.  相似文献   
38.
This paper reviews the early development of design requirements for seismic events in US early developing US nuclear electric generating fleet. Notable safety studies, including WASH-1400, Sandia Siting Study, and the NUREG-1150 probabilistic risk study are briefly reviewed in terms of their relevance to extreme accidents arising from seismic and other severe accident initiators. Specific characteristic about the nature of severe accidents in nuclear power plants are reviewed along with present day state of art analysis methodologies (MELCOR and MACCS) that are used to evaluate severe accidents and to optimize mitigative and protective actions against such accidents. I is the aim of this paper to make nuclear operating nations aware of the risks that accompany a much needed energy resource and to identify some of the tools, techniques and landmark safety studies that serve to make the technology more safe and to maintain vigilance and adequate safety culture for the responsible management of this valuable but unforgiving technology.  相似文献   
39.
Flowline bundle system consisting of carrier pipe,sleeve pipe and internal flowlines offers innovative solution for the infield transportation of oil and gas. Due to its features,flowline bundle offers a couple of advantages over conventional flowline in particular for cases where multi-flowlines and high thermal performance is of great interest. The main benefits and advantages of such system include excellent thermal performance to prevent wax formation and hydrates,multiple bundled flowlines,mechanical and corrosion protection,potential reuse, etc. With the developments of offshore oil and gas industries,more and more hydrocarbon resources are being explored and discovered from shallow to deep water. Pipeline bundle system can be a smart solution for certain applications,which can be safe and cost effective solution. The objective of this paper is to overview pipeline bundle technology,outline detailed engineering design issue and procedure. Focus is given to its potential application in offshore for infield transportation. Engineering design principles and procedures for pipeline bundle system are highlighted. Construction methods of flowline bundle onshore are reviewed. Offshore towing and installation of pipeline bundle procedure is outlined.  相似文献   
40.
道路危险货物运输管理信息系统框架设计   总被引:1,自引:0,他引:1  
为了加强道路危险货物运输管理,确保危险货物运输安全,从系统的观点,综合运用智能运输系统(ITS)、全球卫星定位系统(GPS)、地理信息系统(GIS)、全球移动通讯系统(GSM)、通用无线分组业务(GPRS)和计算机网络等多方面知识,根据道路危险货物运输的特点,基于国家ITS体系框架,确定了道路危险货物运输管理信息系统的4大服务主体、6类用户主体,明确了系统的用户需求,构建了系统的逻辑框架和物理框架.为道路危险货物运输管理信息系统的建设作了理论铺垫.  相似文献   
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