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81.
Summary The BALB/c mouse developed mesangial deposits of immune constituents and light microscopical changes characteristic of immune complex glomerulonephritis after 8 weeks' treatment with mercuric chloride given by s.c. injection. There were no signs of linear of granular immune deposits along the glomerular capillary basement membrane after 2 or 8 weeks. The antigen could not be identified. No antibodies to nuclear or renal structures were found. Using a histochemical method (silver amplification) mercury was detected by light and electron microscopy in tubular and glomerular structures. Mercury was present in secondary lysosomes of the mesangial cells after eight weeks of mercury poisoning.We are deeply indebted to Dr. Gorm Danscher, Institute of Anatomy, B., University of Aarhus, Denmark, for valuable discussions and technical advice. This work was supported by the Swedish Medical Research Council, project no 6536. 相似文献
82.
最大Meta路及其在供应链建模与分析中的应用 总被引:4,自引:0,他引:4
对供应链建模与分析研究现状进行简述,并介绍笔者先前提出的基于Meta图的供应链建模方法;在此基础上提出最大Meta路的概念,并给出其数学定义;提出基于Meta图邻接矩阵传递闭包的最大Meta路的算法,并对其算法复杂度进行分析,结果表明该算法的复杂度为多项式的;通过实例对最大Meta路在供应链建模及其结构分析中的应用进行讨论,计算结果表明这是一种十分有效的供应链组建事前定量分析评价方法。 相似文献
83.
R. Kittelberger P. F. Davis W. E. Stehbens 《Cellular and molecular life sciences : CMLS》1990,46(3):264-267
Summary Diffuse intercellular immunofluorescence staining of type VI collagen was found in the experimentally thickened vascular wall and in control blood vessel tissues as well, superimposed by more intense staining around basement membranes. While the basement membrane staining disappeared in advanced mural thickenings, the diffusely distributed network of type VI collagen remained. 相似文献
84.
HE Yuhong LI Xianghui WANG Fu XUE Yi & SUI Senfang Department of Biological Sciences & Biotechnology State Key Labora-tory of Biomembrane Tsinghua University Beijing China 《科学通报(英文版)》2003,48(17)
Neurotransmitter release from presynaptic neurons into the synaptic cleft is an essential step in neurotrans-mission. The release is triggered by Ca2+ and completed by the fusion of neurotransmitters containing synaptic vesicles with the presynaptic membrane. Over the last decades, there has been a virtual explosion in identifica-tion of proteins that play critical roles in the release proc-ess. The leading candidates proposed as the Ca2+-sensors that regulate fusion are members of the synapt… 相似文献
85.
林森杰 《厦门大学学报(自然科学版)》2006,45(Z2):225-232
目前有关Pfiesteria piscicidaSte ind inger et Burkholder的摄食行为研究已有相当多的报道,然而这种生物是如何应用蛋白的还没有人做过研究.我们研究了P.piscicida依赖于血清蛋白的生长能力,发现不管添不添加其捕食者Rhodom onassp.,仅仅1 h后,添加了动物血清的实验组就比未添加血清的对照组显示出明显出更快的生长速率,这种活跃的生长至少持续了4 h.当添加了异硫氰酸荧光素的共扼免疫蛋白后,在P.piscicida的细胞中检测到了荧光;第1个小时只能检测到微弱的荧光,此后荧光逐渐增强,到3~4h达到最强.此外,我们还进一步通过蛋白质印迹法来验证P.piscicida细胞对血清蛋白质的吸收.本研究首次提供了沟鞭藻能够消化利用蛋白质的直接证据,并且发现P.piscicida生长响应与动物蛋白的添加几乎是同步的.尽管细胞快速生长机制还有待进一步研究,但我们的发现可能解释了P.piscicida是如何得益于其吞噬摄食方式及如何在鱼类出现时作出快速反应的. 相似文献
86.
本文重点介绍了采用滤波解调技术获取振动信号中的故障特征,然后利用脉冲冲击定量诊断技术分析故障部位与故障严重程度,同时叙述了利用故障提取技术、故障定量诊断技术、嵌入式技术、计算机网络技术相结合,实现设备关键传动部件在线监测与故障定量诊断的技术应用,为进一步研究大型设备传动部件的在线监测系统提供参考。 相似文献
87.
为了实现连云港旅游业跨越式发展,科学的旅游资源评价是其旅游资源优化组合和合理开发规划的前提;在实地考察和数据分析的基础上,根据连云港滨海旅游资源的特点,利用层次分析法(AHP法)与特尔菲法(Delphi法),建立了针对这种滨海旅游资源类型的评价体系,得到各评价因子的权重、分值及综合评分值,最后对其进行等级划分,实现了连云港市滨海旅游资源的定量评价;结果表明连云港旅游资源类型具有一定的独特性,景点等级较高,自然环境保护较好,整体级别较高,具有较广泛的旅游市场;但由于受目前开发力度和深度等相关因素的影响,研究区吸引向性基本面向国内,具有较高的发展潜力. 相似文献
88.
可罚的违法性理论是大陆法系中违法性论中的重要内容,其以刑法的谦抑性为内核,以消极认定犯罪为功能.作为一个发展完善的理论,可罚的违法性理论的引入,能够很好地解决我国现存犯罪构成理论缺乏出罪事由的弊端,同时对于未来的刑法改革也具有多方面的借鉴价值. 相似文献
89.
Ramzi Chalghaf Walid Oueslati Marwa Ammar Hafsia Ben Rhaiem AbdesslemBen Haj Amara 《自然科学进展(英文版)》2013,23(1):23-35
This work aims at investigating the strain effect,created by varying pH solution and continuous heating cycle,on the cation exchange process in the case of Na-rich montmorillonite sample in contact with bi-ionic solution with variable concentration,saturated respectively by Co2+ and Cu2+ cations.The ionic exchange process is characterized using XRD analysis obtained through the comparison of experimental XRD patterns with calculated ones,which allowed us to determine several structural parameters related to the nature,abundance,size,position and organization of exchangeable cation and water molecule in the interlamellar space along the caxis.Indeed,the proposed theoretical models,for the stressed samples,show that the structure presents an interstratified hydration character and proves the coexistence of more than two ’’crystallite’’ specie in the structure.The perturbation types have an obvious effect on the selective exchange process for all stressed samples,where the interlayer space is characterized by the coexistence of more one exchangeable cation. 相似文献
90.
Quanzhao Yue Lin Liu Wenchao Yang Taiwen Huang Jun Zhang Hengzhi Fu Xinbao Zhao 《自然科学进展(英文版)》2017,27(2):236-243
The influence of withdrawal rate on the porosity in a third-generation Ni-based single crystal superalloy was investigated by a quantitative evaluation method. The results showed that the withdrawal rate obviously effected on the average area fraction, number and diameter of porosities except their radius ratios. In consideration of the microstructure observation for dendrite arms, an optimized withdrawal rate was obtained with a minimum porosity level as about 125 μm s~(-1). Simultaneously, a threshold value for the acceptance level of porosities might be set as about 0.1% in order to fulfill the requirements for Ni-based single crystal casting in laboratory scale. Finally, the formation reason of porosity was discussed and it was concluded that the feeding for the volume shrinkage of the last solidified eutectic liquids from the residual liquids and the isolating effect of the morphologies of dendrite arms might be two key factors in controlling the porosities level in Ni-based single crystal superalloy. 相似文献