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991.
Complement C3 gene expression and regulation in human glomerular epithelial cells. 总被引:12,自引:0,他引:12 下载免费PDF全文
Extra-hepatic synthesis of complement is thought to mediate local tissue inflammatory injury. To investigate this phenomenon in the glomerular epithelial cell (GEC), we examined the biosynthesis and regulation of gene expression of the third component of complement in isolated human GEC derived from normal tissue. Metabolic labelling and immunoprecipitation studies demonstrated that C3 protein was synthesized, processed and secreted by GEC under basal conditions. The secreted C3 alpha and beta polypeptide chains had identical electrophoretic mobilities with those of hepatic C3. Examination of cellular RNA using semi-quantitative polymerase chain reaction (PCR) showed that C3 gene expression was present in unstimulated GEC and was increased by stimulation with interferon-gamma (IFN-gamma) in a time- and dose-dependent manner. Tumour necrosis factor-alpha (TNF-alpha), while mediating an increase in monocyte U937 C3 expression, revealed no evidence of regulation of GEC C3 gene expression. These results indicate that human GEC spontaneously express the C3 gene and that increased gene expression is regulated by IFN-gamma. These observations may reflect part of a wider mechanism of protection against or mediation of local, immune-mediated tissue injury. 相似文献
992.
Haijo Jung Hee-Joung Kim Sang-Ho Lee Sae-Rome Kim Chang Lyong Ji Jung-Han Kim Sun Kook Yoo Ki-Hwang Kim 《Journal of digital imaging》2004,17(2):100-108
This study evaluated the migration to full-PACS of medical image data archived using mini-PACS at two hospitals of the Yonsei University Medical Center, Seoul, Korea. A major concern in the migration of medical data is to match the image data from the mini-PACS with the hospital OCS (Ordered Communication System). Prior to carrying out the actual migration process, the principles, methods, and anticipated results for the migration with respect to both cost and effectiveness were evaluated. Migration gateway workstations were established and a migration software tool was developed. The actual migration process was performed based on the results of several migration simulations. Our conclusions were that a migration plan should be carefully prepared and tailored to the individual hospital environment because the server system, archive media, network, OCS, and policy for data management may be unique. 相似文献
993.
涎腺癌肉瘤临床及病理分析 总被引:6,自引:0,他引:6
目的:探讨涎腺癌肉瘤的临床病理学特点及其鉴别诊断。方法:对3例涎腺癌肉瘤患者的临床资料进行回顾性研究并复习相关文献,对全部病例的组织学标本重新进行镜下观察。结果:涎腺癌肉瘤临床表现常为迅速增大的颜面部肿物并伴疼豢。光匀下组织学观察常可见肉瘤和癌两种成分并存,癌多为鳞状细胞癌和腺癌,肉瘤以骨或软骨肉瘤为主。结论:涎腺癌肉瘤的临床特点与涎腺其他恶性肿瘤较难区别,但涎腺癌肉瘤的恶性程度极高。 相似文献
994.
Lura Brianna Caddle Jeremy L. Grant Jin Szatkiewicz Johann van Hase Bobbi-Jo Shirley Joerg Bewersdorf Christoph Cremer Alain Arneodo Andre Khalil Kevin D. Mills 《Chromosome research》2007,15(8):1061-1073
Radiation exposure is an occupational hazard for military personnel, some health care professionals, airport security screeners,
and medical patients, with some individuals at risk for acute, high-dose exposures. Therefore, the biological effects of radiation,
especially the potential for chromosome damage, are major occupational and health concerns. However, the biophysical mechanisms
of chromosome instability subsequent to radiation-induced DNA damage are poorly understood. It is clear that interphase chromosomes
occupy discrete structural and functional subnuclear domains, termed chromosome territories (CT), which may be organized into
‘neighborhoods’ comprising groups of specific CTs. We directly evaluated the relationship between chromosome positioning,
neighborhood composition, and translocation partner choice in primary lymphocytes, using a cell-based system in which we could
induce multiple, concentrated DNA breaks via high-dose irradiation. We critically evaluated mis-rejoining profiles and tested
whether breaks occurring nearby were more likely to fuse than breaks occurring at a distance. We show that CT neighborhoods
comprise heterologous chromosomes, within which inter-CT distances directly relate to translocation partner choice. These
findings demonstrate that interphase chromosome arrangement is a principal factor in genomic instability outcomes in primary
lymphocytes, providing a structural context for understanding the biological effects of radiation exposure, and the molecular
etiology of tumor-specific translocation patterns. 相似文献
995.
Two newly characterized germinal center B-cell-associated genes,GCET1 and GCET2, have differential expression in normal and neoplastic B cells 总被引:2,自引:0,他引:2 下载免费PDF全文
Pan Z Shen Y Du C Zhou G Rosenwald A Staudt LM Greiner TC McKeithan TW Chan WC 《The American journal of pathology》2003,163(1):135-144
996.
997.
血管内皮生长因子反义基因转染对高转移人巨细胞肺癌细胞系生 … 总被引:1,自引:1,他引:1
目的 探讨反义血管内皮生长因子(VEGF)基因转染在抑制恶性肿瘤生长和转移的抗肿瘤血管基因治疗中的意义。方法 利用基因重组技术构建正义和反义VEGF121 cDNA真核表达载体,用脂质体法转染高转移性人巨细胞肺癌细胞(PG),经Northem杂交和Western印迹免疫化学检测VEGF mRNA和蛋白质的表达水平,并对转染前后细胞进行体外生长和裸鼠体内生长转移等多项生物学行为实验,结果 转染反义转 相似文献
998.
耳穴电参数时变关系实验表明,在测量起始t<2τ时,因瞬变作用,电位E(t)和压降U(t)为瞬态响应,响应函数呈指数关系,特征参数为弛豫时间τ,τ≈RC;t>2τ时,为时变间期。电路分析给出数学描述,并与耳穴和模拟实验结果较相符。提示,时变特征应以t>2τ后提取,静态电测量时,采样应避开瞬变期,可提高准确性。该工作对正确鉴别时变性和特征提取,全面认识耳穴电特性具有重要意义。 相似文献
999.
1000.
Hepatocytes are anchorage-dependent cells sensitive to microenvironment; the control of the physicochemical properties of the extra-cellular matrices may be useful to the maintenance of hepatocyte functions in vitro for various applications. In a microcapsule-based 3-D hepatocyte culture microenvironment, we could control the physical properties of the collagen nano-fibres by fine-tuning the complex-coacervation reaction between methylated collagen and terpolymer of hydroxylethyl methacrylate-methyl methacrylate-methylacrylic acid. The physical properties of the nano-fibres were quantitatively characterized using back-scattering confocal microscopy to help optimize the physical support for hepatocyte functions. We further enhanced the chemical properties of the collagen nano-fibres by incorporating galactose onto collagen, which can specifically interact with the asialoglycoprotein receptor on hepatocytes. By correlating a range of collagen nano-fibres of different physicochemical properties with hepatocyte functions, we have identified a specific combination of methylated and galactosylated collagen nano-fibres optimal for maintaining hepatocyte functions in vitro. A model of how the physical and chemical supports interplay to maintain hepatocyte functions is discussed. 相似文献