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排序方式: 共有1013条查询结果,搜索用时 15 毫秒
91.
92.
Ares-Carrasco S Picatoste B Camafeita E Carrasco-Navarro S Zubiri I Ortiz A Egido J López JA Tuñón J Lorenzo O 《Journal of Proteomics》2012,75(6):1816-1829
Diabetes with or without the presence of hypertension damages the heart. However, there is currently a lack of information about these associated pathologies and the alteration of linked proteins. For these reasons, we were interested in the potential synergistic interaction of diabetes and hypertension in the heart, focusing on the proteome characterization of the pathological phenotypes and the associated hypertrophic response. We treated normotensive and spontaneously hypertensive (SHR) rats with either streptozotocin or vehicle. After 22 weeks, type-I diabetic (DM1), SHR, SHR/DM1 and control left-ventricles were studied using proteomic approaches. Proteomics revealed that long-term DM1, SHR and SHR/DM1 rats exhibited 24, 53 and 53 altered proteins in the myocardia, respectively. DM1 myocardium showed over-expression of apoptotic and cytoskeleton proteins, and down-regulation of anti-apoptotic and mitochondrial metabolic enzymes. In both SHR and SHR/DM1 these changes were exacerbated and free fatty-acid (FFA) ß-oxidation enzymes were additionally decreased. Furthermore, SHR/DM1 hearts exhibited a misbalance of specific pro-hypertrophic, anti-apoptotic and mitochondrial ATP-carrier factors, which could cause additional damage. Differential proteins were validated and then clustered into different biological pathways using bioinformatics. These studies suggested the implication of FFA-nuclear receptors and hypertrophic factors in these pathologies. Although key ß-oxidation enzymes were not stimulated in DM1 and hypertensive hearts, peroxisome proliferator-activated receptors-α (PPARα) were potentially activated for other responses. In this regard, PPARα stimulation reduced hypertrophy and pro-hypertrophic factors such as annexin-V in high-glucose and angiotensin-II induced cardiomyocytes. Thus, activation of PPARα could reflect a compensatory response to the metabolic-shifted, apoptotic and hypertrophic status of the hypertensive-diabetic cardiomyopathy. 相似文献
93.
Natural selection and ecological adaptation are ultimately responsible for much of the origin of biodiversity. Yet, the identification of divergent natural selection has been hindered by the spatial complexity of natural systems, the difficulty in identifying genes under selection and their relationship to environment, and the confounding genomic effects of time. Here, we employed genome scans, population genetics and sequence-based phylogeographic methods to identify divergent natural selection on population boundaries in a freshwater invader, the Amazonian pufferfish, Colomesus asellus. We sampled extensively across markedly different hydrochemical settings in the Amazon Basin and use 'water colour' to test for ecological isolation. We distinguish the relative contribution of natural selection across hydrochemical gradients from biogeographic history in the origin and maintenance of population boundaries within a single species and across a complex ecosystem. We show that spatially distinct population structure generated by multiple forces (i.e. water colour and vicariant biogeographic history) can be identified if the confounding effects of genetic drift have not accumulated between selective populations. Our findings have repercussions for studies aimed at identifying engines of biodiversity and assessing their temporal progression in understudied and ecologically complex tropical ecosystems. 相似文献
94.
目的:探讨CO2激光联合胸腺五肽治疗尖锐湿疣的临床疗效。方法:将我院2010年2月-2011年8月期间收治的82例尖锐湿疣患者随机分为两组,治疗组50例采用CO2激光器治疗联合胸腺五肽肌注;对照组32例单纯采用CO2激光器治疗;两组治疗疗程结束后观察临床疗效。结果:治疗组50例,一次治愈者46例,占92%;二次治愈者4例,占8%。对照组32例,一次治愈者19例,占59.4%;二次治愈者13例,占40.6%。两组一次治愈率比较差异明显,具有统计学意义(P<0.05)。两组术后局部轻度水肿和疼痛,无需处理1~3天缓解或痊愈。结论:CO2激光联合胸腺五肽治疗尖锐湿疣临床疗效好,并具有治疗简便,术后不良反应少,治愈率高等特点。 相似文献
95.
Genomic DNA was extracted from wild-type Escherichia coli strains ATCC 35321 and 8677. The lac Z gene was amplified and used as a template for in vitro synthesis of β-galactosidase. In addition the enzyme was synthesized
in vitro with a C-terminal His6 tag. The enzyme expression was also induced in these strains using isopropyl-β-D-galactoside. Single enzyme molecule assays were performed using a capillary electrophoresis-based protocol on both the in
vitro and in vivo synthesized enzyme. In vivo produced enzyme from strains 35321 and 8677 showed average combined turnover
numbers for the 4 active sites of the individual enzyme molecules of 53,400 ± 18,400 (N = 139) and 34,300 ± 17,800 min−1 (N = 181) respectively. Average combined turnover numbers of 35,800 ± 20,900 (N = 302) and 31,700 ± 17,700 min−1 (N = 315) were obtained respectively for the in vitro synthesized enzyme from strain 35321 with the absence and presence of
a C-terminal His6 tag. For strain 8677, the average combined turnover numbers were 29,000 ± 17,900 (N = 288) and 25,200 ± 12,600 min−1 (N = 240) respectively for the absence and presence of a C-terminal His6 tag. The average combined turnover numbers of the enzyme from both strains synthesized in vivo and in vitro and with the
presence and absence of a His6 tag were found to differ significantly. This indicates that the in vivo and in vitro produced enzymes are not identical and
the presence of a C-terminal His6 tag alters the activity of β-galactosidase. 相似文献
96.
Éva Hideg 《Central European Journal of Biology》2008,3(3):273-284
Four fluorescent singlet oxygen sensors: DanePy, its oxalate salt, Singlet Oxygen Sensor Green and MVP, were infiltrated into
tobacco leaves and tested for toxicity, subcellular localization, light sensitivity and capacity to trap the singlet oxygen
produced in photoinhibition. For reference, a broad sensitivity free radical probe, TEMPO-9-AC, was also included. Photochemical
yield was approximately 15% and 10% inhibited by Singlet Oxygen Sensor Green and MVP, respectively, but was not significantly
affected by the other probes. Under photoinhibitory conditions, brought about by irradiating lincomycin-treated leaves with
strong photosynthetically active radiation, DanePy and Singlet Oxygen Sensor Green were responsive. Singlet Oxygen Sensor
Green was also reactive to low, non-photoinhibitory light exposure of the leaf, which was not characteristic to the other
probes. MVP did not respond to singlet oxygen which can partly be explained by a possible attenuation of its blue emission
in the leaf, as shown by the example TEMPO-9-AC. DanePy-oxalate did not respond to photosynthetic singlet oxygen due to lack
of its penetration into photosynthetic tissue and hence could be useful in detecting any singlet oxygen which escapes from
a chloroplast initiation site. DanePy was localized in the chloroplasts, while Singlet Oxygen Sensor Green was mainly found
in the epidermal cells preferentially associated with the nucleus.
相似文献
97.
We constructed fusion proteins consisting of fluorescence-enhanced green fluorescent protein (EGFP) and soluble domain of
duck B-cell-activating factor of the TNF family (dsBAFF). The soluble EGFP/dsBAFF was efficiently expressed in Escherichia
coli BL 21 (DE3) and was purified in milligram amounts using metal chellate affinity chromatography. The fusion protein exhibited
similar fluorescence spectra with free EGFP and promoted the survival of duck bursal B cells in vitro as well as dsBAFF. EGFP/dsBAFF
has shown specific binding to duck BAFF receptors positive-cells and the stained cells could be analyzed with flow cytometry.
Thus, the fusion protein represents a readily obtainable source of biologically active dsBAFF that may prove useful in further
studies on duck BAFF and its receptors. 相似文献
98.
Heterogeneous genomic differentiation between walking-stick ecotypes: "isolation by adaptation" and multiple roles for divergent selection 总被引:4,自引:0,他引:4
Genetic differentiation can be highly variable across the genome. For example, loci under divergent selection and those tightly linked to them may exhibit elevated differentiation compared to neutral regions. These represent "outlier loci" whose differentiation exceeds neutral expectations. Adaptive divergence can also increase genome-wide differentiation by promoting general barriers to neutral gene flow, thereby facilitating genomic divergence via genetic drift. This latter process can yield a positive correlation between adaptive phenotypic divergence and neutral genetic differentiation (described here as "isolation-by-adaptation"). Here, we examine both these processes by combining an AFLP genome scan of two host plant ecotypes of Timema cristinae walking-sticks with existing data on adaptive phenotypic divergence and ecological speciation in these insects. We found that about 8% of loci are outliers in multiple population comparisons. Replicated comparisons between population-pairs using the same versus different host species revealed that 1-2% of loci are subject to host-related selection specifically. Locus-specific analyses revealed that up to 10% of putatively neutral (nonoutlier) AFLP loci exhibit significant isolation-by-adaptation. Our results suggest that selection may affect differentiation directly, via linkage, or by facilitating genetic drift. They thus illustrate the varied and sometimes nonintuitive contributions of selection to heterogeneous genomic differentiation. 相似文献
99.
以小麦叶肉细胞原生质体为材料,通过免疫荧光标记和Ca~(2 )荧光染料的装载并结合药物学试验,借助激光共聚焦扫描显微镜观察,探讨微管骨架和Ca~(2 )之间的内在联系。试验结果表明,[Ca~(2 )]_(cyt)的升高能够诱发微管骨架的解聚;而微管骨架的解聚也会促使胞外Ca~(2 )内流,进而造成[Ca~(2 )]_(cyt)的升高。 相似文献
100.
人肝癌细胞系HHCC中CD147和MMP—2共存了的免疫组织化学研究 总被引:2,自引:0,他引:2
应用免疫组织化学ABC法结合激光共聚焦显微镜观察了CD147分子和MMP-2在人肝癌HHCC细胞系中的表达,结果表明在HHCC细胞中CD147分子和MMP-2均呈免疫反应阳性,CD147反应位于核膜和核周胞质,MMP-2反应位于胞浆。 相似文献