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101.
实验性糖尿病对小鼠肝脏酶组织化学和超微结构的影响 总被引:8,自引:0,他引:8
实验用四氧嘧啶建造糖尿病动物模型,8周后取肝作组织学、酶组织化学和超微结构的观察,以探讨实验性糖尿病对肝组织结构和功能的影响。表明在糖尿病状态下,肝细胞的结构和功能均受到一定的损害。 相似文献
102.
鸡卵黄抗体的制备以及金磁微粒为载体去除人血浆部分高丰度蛋白的研究 总被引:3,自引:0,他引:3
目的:以人血浆白蛋白(HSA)和IgG为免疫原,制备特异性鸡卵黄抗体IgY(Egg yolk immunoglobulin),并将其固定于金磁微粒表面,用于HSA和IgG的去除研究.方法:用HSA、IgG以及混合成分分别作免疫原免疫Roman母鸡.制备抗HSA和IgG鸡卵黄抗体IgY,并对IgY的分离提取条件进行优化.SDS-PAGE和间接ELISA检测IgY的纯度和效价.将高效价IgY固定于金磁颗粒表面进行血浆高丰度蛋白去除研究.结果:免疫后60~120 d内,鸡血清抗体效价可达1∶15 000~1∶25 000;收获鸡蛋,提取得到的卵黄抗体IgY效价可达1∶10000~1∶25000,纯度98%以上;采用金磁微粒载体固定IgY,可对血浆中的HSA,IgG进行特异性的去除.结论:人血浆中的高丰度蛋白成分HSA和IgG免疫产蛋母鸡后,可从鸡卵黄中分离提取到高效价、高纯度的卵黄抗体IgY;IgY偶联于金磁微粒表面可特异性的去除人血浆中的HSA和IgG,作为血浆蛋白质组学研究的一种新方法,有较好的应用前景. 相似文献
103.
104.
Colgin LL Kubota D Brucher FA Jia Y Branyan E Gall CM Lynch G 《Journal of neurophysiology》2004,92(6):3385-3398
Spontaneous negative-going potentials occurring at an average frequency of 0.7 Hz were recorded from the dentate gyrus of slices prepared from the temporal hippocampus of young adult rats. These events (here termed "dentate waves") in several respects resembled the dentate spikes described for freely moving rats during immobile behaviors and slow-wave sleep. Action potentials were observed on the descending portion of the in vitro waves and, as expected from this, whole cell recordings established that the waves were composed of depolarizing currents. Dentate waves appeared to be locally generated within the granule cell layer and were greatly reduced by antagonists of AMPA-type glutamate receptors or by lesions to the entorhinal cortex. Simultaneous recordings indicated that the waves were often synchronized in the inner and outer blades of the dentate gyrus. Knife cuts through the perforant path and the commissural/associational system did not eliminate synchronization, leaving electrotonic propagation via gap junctions as its probable cause. In accord with this, cuts that separated the two blades of the dentate eliminated synchronization between them, and a compound that inhibits gap junctions reduced wave activity. Dentate waves were regularly accompanied by sharp waves in field CA3 and were reduced in size by the acetylcholinesterase inhibitor, physostigmine. It is hypothesized that dentate waves occur when spontaneous glutamate release from dentate afferents produces action potentials in neighboring granule cells that then summate electrotonically into a population event; once initiated, the waves propagate, again electrotonically, and thereby engage a significant portion of the granule cell population. 相似文献
105.
Immunohistochemical analysis of centromere protein F expression in buccal and gingival squamous cell carcinoma 总被引:4,自引:0,他引:4
Centromere protein F (CENP-F) expression (localization and characteristics) in relation to tumor clinicopathological parameters was immunohistochemically examined and evaluated in 47 archival biopsy specimens of buccal and gingival squamous cell carcinomas (SCC). Centromere protein F expression was detected in 79% of the samples. An increase in the labeling index (LI) with WHO grading was obtained ( P < 0.05). Correlations were obtained between the CENP-F LI and tumor size ( P < 0.05). Immunoelectron microscopy showed CENP-F nuclear staining as punctate or fine dots. The present study shows that CENP-F expression and detection of a more specific cell subpopulation presents a theoretical advantage for the analysis of the precise cell cycle of G2 to M cells, compared to Ki-67. 相似文献
106.
107.
Springer Link及其收录的医学期刊分析 总被引:4,自引:0,他引:4
目的:向图书馆员和用户介绍Springer Link,对其收录的医学期刊进行深入分析,使该数据库得到更好的利用。方法利用《外国报刊目录》和美国《医学索引》(IM)的《引用期刊一览表》等对Springer Link收录的英文医学期刊从权威性、出版地分布、学科分布和收藏年限等方面进行考查。结果86%的期刊被IM引用,欧洲——尤其是德国的期刊较多,医学各学科都有相应的期刊被收录,但数量分布不均,有所偏重,72.7%的期刊可以保证至少近5年或自创刊以来的文献。结论Springer Link所提供的全文医学期刊服务质量较上乘,并有自己的特色。 相似文献
108.
Contribution of the twin arginine translocation system to the virulence of enterohemorrhagic Escherichia coli O157:H7 总被引:3,自引:0,他引:3 下载免费PDF全文
Shiga toxin-producing Escherichia coli O157:H7 is a major food-borne infectious pathogen. In order to analyze the contribution of the twin arginine translocation (TAT) system to the virulence of E. coli O157:H7, we deleted the tatABC genes of the O157:H7 EDL933 reference strain. The mutant displayed attenuated toxicity on Vero cells and completely lost motility on soft agar plates. Further analyses revealed that the ΔtatABC mutation impaired the secretion of the Shiga toxin 1 (Stx1) and abolished the synthesis of H7 flagellin, which are two major known virulence factors of enterohemorrhagic E. coli O157:H7. Expression of the EDL933 stxAB1 genes in E. coli K-12 conferred verotoxicity on this nonpathogenic strain. Remarkably, cytotoxicity assay and immunoblot analysis showed, for the first time, an accumulation of the holotoxin complex in the periplasm of the wild-type strain and that a much smaller amount of StxA1 and reduced verotoxicity were detected in the ΔtatC mutant cells. Together, these results establish that the TAT system of E. coli O157:H7 is an important virulence determinant of this enterohemorrhagic pathogen. 相似文献
109.
Jiang X Gao X Zheng H Yan M Liang W Shao Z Li W Zhang E Hu Y Hai R Yu D Kan B Xu J 《Clinical and diagnostic laboratory immunology》2004,11(6):1182-1184
Specific immunoglobulin G antibody for severe acute respiratory syndrome (SARS) coronavirus was detected in maternal blood, umbilical blood, and amniotic fluid from a pregnant SARS patient. Potential protection of fetus from infection was suggested. 相似文献
110.