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91.
目的探讨CDC2及CLDN5在食管鳞癌中表达及其临床病理特征的关系。方法应用免疫组化Elivision法检测90例食管鳞癌组织、28例正常食管黏膜组织及16例重度不典型增生组织中CDC2和CLDN5的蛋白表达情况。结果在食管鳞癌和正常食管黏膜组织中CDC2和CI。DN5的阳性表达率分别为88.89%(80/90)、85.56%(77/90)和48.86%(12/28)、25.00%(7/28),两者差异有统计学意义(P〈O.05)。CDC2蛋白表达在低分化食管鳞癌中明显高于高分化食管鳞癌;临床分期Ⅲ+Ⅳ期组的CDC2蛋白的表达显著高于I期、Ⅱ期组(P〈O.05)。CDC2和CLDN5在食管鳞癌中表达呈正相关(r=0.537,P〈o.05)。结论CDC2和CLDN5在食管鳞癌的发生、发展过程中可能发挥重要作用,可能作为食管癌临床早期诊断的重要指标。  相似文献   
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Copper is a trace element that is essential for the normal growth and development of all living organisms. In mammals, the ATP7A Cu-transporting ATPase is a key protein that is required for the maintenance of copper homeostasis. In both humans and mice, the ATP7A protein is coded by the X-linked ATP7A/Atp7a gene. Disturbances in copper metabolism caused by mutations in the ATP7A/Atp7a gene lead to severe metabolic syndromes Menkes disease in humans and the lethal mottled phenotype in mice. Mosaic is one of numerous mottled mutations and may serve as a model for a severe Menkes disease variant. In Menkes patients, mutations in the ATP7A gene often result in a decreased level of the normal ATP7A protein. The aim of this study was to analyse the expression of the Atp7a gene in mosaic mutants in early postnatal development, a critical period for starting copper supplementation therapy in both Menkes patients and mutant mice. Using real-time quantitative RT-PCR, we analysed the expression of the Atp7a gene in the brain, kidney and liver of newborn (P0.5) and suckling (P14) mice. Our results indicate that in mosaic P0.5 mutants, the Atp7a mRNA level is decreased in all analysed organs in comparison with wild-type animals. In two week-old mutants, a significant decrease was observed only in the kidney. In contrast, their hepatic level of Atp7a tended to be higher than in wild-type mice. We speculate that disturbance in the expression of the Atp7a gene and, consequently, change in the copper concentration of the organs, may contribute to the early fatal outcome of mosaic males.  相似文献   
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To explore the proteomic changes of placental trophoblastic cells in preeclampsia–eclampsia (PE), placental trophoblastic cells from normally pregnant women and women with hypertension during gestational period were prepared by laser capture microdissection (LCM), and proteins isolated from these cells were subjected to labeling and proteolysis with isotope-coded affinity tag reagent. A qualitative and quantitative analysis of the proteome expression of placental trophoblastic cells was made using two-dimensional liquid chromatography tandem mass spectrometry (2D LC–MS/MS). A total of 831 proteins in placental trophoblastic cells were identified by combined use of LCM technique and 2D LC–MS/MS. The result was superior to that of conventional two-dimensional electrophoresis method. There were marked differences in 169 proteins of placental trophoblastic cells between normally pregnant women and women with PE. Of 70 (41.4 %) proteins with more than twofold differences, 31 proteins were down-regulated, and 39 were up-regulated in placental trophoblastic cells of the woman with PE. Laminin expression in placenta trophoblastic cells of women with PE was significantly down-regulated as confirmed by Western blot analysis. These findings provide insights into the proteomic changes in placental trophoblastic cells in response to PE and may identify novel protein targets associated with the pathogenesis of PE.  相似文献   
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Herpes simplex virus type 1 (HSV-1) is a large, neurotropic, double-stranded DNA virus that establishes a lifelong latent infection in neurons and glial cells. Previous studies reveal that several metabolic perturbations are associated with HSV-1 infection. However, the extracellular metabolic alterations associated with HSV-1 infection have not been systematically profiled in human cells. Here, a proton nuclear magnetic resonance-based metabonomic approach was applied to differentiate the extracellular metabonomic profiles of HSV-1 infected human oligodendroglia cells (n = 18) and matched control cells (n = 18) at three time points (12, 24, and 36 h post-infection). Resulting spectra were analyzed by chemometric and statistical methods. Metabonomic profiling revealed perturbations in 21 extracellular metabolites. Partial least squares discriminant analysis demonstrated that the whole metabolic patterns enabled statistical discrimination between HSV-1 infected human oligodendroglia cells and control cells. Eight extracellular metabolites, seven of which were amino acids, were primarily responsible for score plot discrimination between HSV-1 infected human oligodendroglia cells and control cells at 36 h post-infection: alanine, glycine, isoleucine, leucine, glutamate, glutamine, histidine, and lactate. HSV-1 infection alters amino acid metabolism in human oligodendroglia cells cultured in vitro. HSV-1 infection may disturb these host cellular pathways to support viral replication. Through elucidating the extracellular metabolic changes incident to HSV-1 infection, this study also provides future directions for investigation into the pathogenic mechanism of HSV-1.  相似文献   
99.
The moose (Alces alces cameloides) population in northeastern China is on the southernmost edge of its distribution in Asia. A survey was conducted to determine moose resource selection and the effects of human disturbance on moose in a study area of 20,661 ha located on the northwestern slope of the Lesser Khingan Mountains, located in northeastern China. Predictive models of resource selection were developed using logistic and autologistic regression. All models considered resource variable selection at two spatial scales, patch and landscape. At the patch scale, moose preferred larger birch (Betula platyphylla) patches, but avoided larger tamarack (Larix gmelinii) patches. At the landscape scale, moose preferred higher densities of tamarack patches, i.e., heterogeneity of tamarack stands, selected areas with more abundant annual shoots, terrain conducive to better concealment, higher altitudes and areas saturated with soil moisture. Roads and forest harvest intervals were identified as important human disturbance factors. This is the first time that moose have been reported to avoid roads, and the avoidance distance was nearly 3 km. We believe that in this region moose under the influence of roads are behaviorally plastic, compared with the indifference of moose to the presence of roads in other regions. Moose avoided forest areas logged more than 3 years previously and preferred areas logged 1–2 years previously. In addition, it may be necessary to monitor the effect of the dynamic of density of roe deer on the spatial distribution of the moose population.  相似文献   
100.
Neuromedin U (NMU) is a brain-gut peptide, which peripherally stimulates smooth muscle, increases of blood pressure, alters ion transport in the gut, controls local blood flow, and regulates adrenocortical function. Although intracerebroventricular (i.c.v.) administration of NMU is known to decrease food intake and body weight, little is known about its effect on other physiological functions. We examined the effects of i.c.v. administration of NMU on mean arterial pressure (MAP), heart rate (HR), and plasma norepinephrine in conscious rats. Neuromedin U (0.05 and 0.5 nmol) provoked an increase in MAP (93.8 +/- 0.5 to 123.5 +/- 1.7 and 94.7 +/- 0.8 to 132.7 +/- 3.0 mm Hg, respectively) and HR (334.9 +/- 6.0 to 494.1 +/- 6.9 and 346.3 +/- 3.3 to 475.1 +/- 8.9 beats/min, respectively). In contrast, plasma norepinephrine increased only with a high dose of neuromedin U. Intravenously administered NMU (0.5 nmol) elicited a small and short lasting increase in MAP, compared to that by i.c.v. NMU. These results indicate that central neuromedin U regulates sympathetic nervous system activity and affects cardiovascular function.  相似文献   
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