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Rapid progress in genome research creates a wealth of information on the functional annotation of mammalian genome sequences. However, as we accumulate large amounts of scientific information we are facing problems of how to integrate and relate the data produced by various genomic approaches. Here, we propose the novel concept of an organ atlas where diverse data from expression maps to histological findings to mutant phenotypes can be queried, compared and visualized in the context of a three-dimensional reconstruction of the organ. We will seek proof of concept for the organ atlas by elucidating genetic pathways involved in development and pathophysiology of the kidney. Such a kidney atlas may provide a paradigm for a new systems-biology approach in functional genome research aimed at understanding the genetic bases of organ development, physiology and disease.Key Words: EuReGene, kidney, genome, development, pathophysiology, genetics  相似文献   
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Lithium–sulfur batteries are attractive for automobile and grid applications due to their high theoretical energy density and the abundance of sulfur. Despite the significant progress in cathode development, lithium metal degradation and the polysulfide shuttle remain two critical challenges in the practical application of Li–S batteries. Development of advanced electrolytes has become a promising strategy to simultaneously suppress lithium dendrite formation and prevent polysulfide dissolution. Here, a new class of concentrated siloxane‐based electrolytes, demonstrating significantly improved performance over the widely investigated ether‐based electrolytes are reported in terms of stabilizing the sulfur cathode and Li metal anode as well as minimizing flammability. Through a combination of experimental and computational investigation, it is found that siloxane solvents can effectively regulate a hidden solvation‐ion‐exchange process in the concentrated electrolytes that results from the interactions between cations/anions (e.g., Li+, TFSI?, and S2?) and solvents. As a result, it could invoke a quasi‐solid‐solid lithiation and enable reversible Li plating/stripping and robust solid‐electrolyte interphase chemistries. The solvation‐ion‐exchange process in the concentrated electrolytes is a key factor in understanding and designing electrolytes for other high‐energy lithium metal batteries.  相似文献   
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Donkey milk and donkey milk kefir exhibit antiproliferative, antimutagenic and antibacterial effects. We investigated the effects of donkey milk and donkey milk kefir on oxidative stress, apoptosis and proliferation in Ehrlich ascites carcinoma (EAC) in mice. Thirty-four adult male Swiss albino mice were divided into four groups as follows: group 1, administered 0.5 ml water; group 2, administered 0.5 ml water + EAC cells; group 3, administered 0.5 ml donkey milk + EAC cells; group 4, administered 0.5 ml donkey milk kefir + EAC cells. We introduced 2.5 x 106 EAC cells into each animal by subcutaneous injection. Tap water, donkey milk and donkey milk kefir were administered by gavage for 10 days. Animals were sacrificed on day 11. After measuring the short and long diameters of the tumors, tissues were processed for histology. To determine oxidative stress, cell death and proliferation iNOS and eNOS, active caspase-3 and proliferating cell nuclear antigen were assessed using immunohistochemistry. A TUNEL assay also was used to detect apoptosis. Tumor volume decreased in the donkey milk kefir group compared to the control and donkey milk groups. Tumor volume increased in the donkey milk group compared to the control group. Proliferating cell nuclear antigen levels were higher in the donkey milk kefir group compared to the control and donkey milk groups. The number of apoptotic cells was less in the donkey milk group, compared to the control, whereas it was highest in the donkey milk kefir group. Donkey milk administration increased eNOS levels and decreased iNOS levels, compared to the control group. In the donkey milk kefir group, iNOS levels were significantly lower than those of the control and donkey milk groups, while eNOS levels were similar to the control group. Donkey milk kefir induced apoptosis, suppressed proliferation and decreased co-expression of iNOS and eNOS. Donkey milk promoted development of the tumors. Therefore, donkey milk kefir appears to be more beneficial for treating breast cancer than donkey milk.  相似文献   
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以ECV304细胞为对象分析登革病毒感染血管内皮细胞的机制.2型登革病毒(DEN2)吸附后微量蚀斑法测定ECV304细胞上清释放的病毒滴度,证实该细胞对DEN2感染有一定的敏感性.机械刮取或胰蛋白酶消化法收集ECV304细胞分离膜蛋白,SDS-PAGE见胰酶处理样品缺失一43 kDa的膜蛋白.将ECV304细胞膜蛋白与35S-Met标记的DEN2进行病毒重叠蛋白结合试验(VOPBA),有29、34和43 kDa的3种膜蛋白可与DV结合,其中29 kDa的蛋白对胰酶耐受.培养的ECV304细胞中加入重组E蛋白(rEgp)对DEN2吸附进行阻断试验,微量蚀斑法与间接免疫荧光表明rEgp抑制DEN2感染该细胞.VOPBA中rEgp可阻断病毒与细胞膜蛋白的结合.结果表明ECV304细胞表面可能存在29、34、43 kDa的3种与DEN2结合的相关蛋白,DEN2 E蛋白可直接介导DV感染血管内皮细胞.  相似文献   
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七姊妹山自然保护区蕨类植物区系地理及资源开发研究   总被引:3,自引:0,他引:3  
张柳  汪正祥  雷耘  方元平  满金山  彭宗林   《广西植物》2006,26(6):665-669
运用植物区系地理分析方法对七姊妹山自然保护区的蕨类植物区系特征进行研究。科的地理区系分析表明,热带、亚热带成分高达58.3%,占主导地位。属的地理区系分析也表明了类似的趋势。种的地理区系分析表明,除了热带、亚热带成分占有较高比例外,温带分布的种也具有较高的比例,占非世界广布种的1.2%。特别是世界温带分布的种占较高比例,达24.2%,这反映了温带成分的重要地位。七姊妹山蕨类植物资源丰富,可区分为药用、观赏、食用、指示类植物等几大类。各种蕨类植物资源显示了广阔的利用前景。  相似文献   
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Structure-activity relationships of biologically active oligosaccharides   总被引:2,自引:0,他引:2  
Abstract. Oligosaccharides that exert biological effects on higher plants (other than as carbon or energy sources) have been termed'oligosaccharins'. A limited number of specific oligo-β-glucans derived from fungal cell walls exhibit oligosaccharin activity, at very low doses, switching on the synthesis of phytoalexins. The structural requirements for this biological activity are stringent, and there is strong evidence that the oligosaccharins of fungal origin act through a receptor in the plant cell membrane. Chemically unrelated oligosaccharins can also be produced by partial digestion of pectins and xyloglucans from higher plant cell walls. In some cases, for example, the α- l -fucosylated oligoxyloglucans that antagonise the growth-promoting effect of auxin, these plant-derived oligosaccharins have relatively strict structural requirements for activity and act at ∼10−6 mol m−3; these may act via specific receptors. In other cases, for example, the growth-promoting action of other oligoxyloglucans, the stringency is somewhat lower and the activity is only seen at ∼10−3 mol m−3, and these oligosaccharins are proposed to influence growth through their ability to modulate the activity of an enzyme, cellulase. A third class of plant-derived oligosaccharins, the oligo-α-galacturonides, appear to have much less stringent structural requirements; a number of unrelated physiological responses are evoked by the same range of oligo-α-galacturonides at ∼10−3 to 1 mol m−3. We suggest that these oligosaccharins may act via a mechanism not involving a specific receptor, perhaps by interacting with the plasma membrane to bring about a change in its physical properties.  相似文献   
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The complexity regarding Shiga toxin-producing Escherichia coli (STEC) in food safety enforcement as well as clinical care primarily relates to the current inability of an accurate risk assessment of individual strains due to the large variety in serotype and genetic content associated with (severe) disease. In order to classify the clinical and/or epidemic potential of a STEC isolate at an early stage it is crucial to identify virulence characteristics of putative pathogens from genomic information, which is referred to as ‘predictive hazard identification’. This study aimed at identifying associations between virulence factors, phylogenetic groups, isolation sources and seropathotypes. Most non-O157 STEC in the Netherlands belong to phylogroup B1 and are characterized by the presence of ehxA, iha and stx 2, but absence of eae. The large variability in the number of virulence factors present among serogroups and seropathotypes demonstrated that this was merely indicative for the virulence potential. While all the virulence gene associations have been worked out, it appeared that there is no specific pattern that would unambiguously enable hazard identification for an STEC strain. However, the strong correlations between virulence factors indicate that these arrays are not a random collection but are rather specific sets. Especially the presence of eae was strongly correlated to the presence of many of the other virulence genes, including all non-LEE encoded effectors. Different stx-subtypes were associated with different virulence profiles. The factors ehxA and ureC were significantly associated with HUS-associated strains (HAS) and not correlated to the presence of eae. This indicates their candidacy as important pathogenicity markers next to eae and stx 2a.  相似文献   
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