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81.
Zenghong Ma Wei Cai Lei Wang Chenglin Du Weiwei Luo Linyu Niu Shuqing Xue Mengxin Ren Xinzheng Zhang Jingjun Xu 《Plasmonics (Norwell, Mass.)》2016,11(6):1481-1486
Magnetic hot spots, which implies confinements and enhancements of magnetic fields, are demonstrated in graphene junctions (GJs) in the mid-infrared range. The appearance of magnetic hot spots in GJs comes from the conduction currents in the junction. In further, the extinction resonance peaks suffer blue shift, along with the increases in the magnetic fields inside junction area, when the junction width reduces. In opposite to the circumstances for electric field enhancements, neither magnetic field enhancements nor resonance frequency of GJs is perturbed by the intrinsic nonlocal electronic response of graphene. Such nonlocality immunized magnetic enhancement could be explained by the polarization dependent property of nonlocal effect. 相似文献
82.
Vincent D Du Fall LA Livk A Mathesius U Lipscombe RJ Oliver RP Friesen TL Solomon PS 《Molecular Plant Pathology》2012,13(5):467-482
In this study, proteomics and metabolomics were used to study the wheat response to exposure to the SnToxA effector protein secreted by the fungal pathogen Stagonospora nodorum during infection. Ninety-one different acidic and basic proteins and 101 metabolites were differentially abundant when comparing SnToxA- and control-treated wheat leaves during a 72-h time course. Proteins involved in photosynthesis were observed to increase marginally initially after exposure, before decreasing rapidly and significantly. Proteins and metabolites associated with the detoxification of reactive oxygen species in the chloroplast were also differentially abundant during SnToxA exposure, implying that the disruption of photosynthesis causes the rapid accumulation of chloroplastic reactive oxygen species. Metabolite profiling revealed major metabolic perturbations in central carbon metabolism, evidenced by significant increases in tricarboxylic acid (TCA) cycle intermediates, suggestive of an attempt by the plant to generate ATP and reducing equivalents in response to the collapse of photosynthesis caused by SnToxA. This was supported by the observation that the TCA cycle enzyme malate dehydrogenase was up-regulated in response to SnToxA. The infiltration of SnToxA also resulted in a significant increase in abundance of many pathogenicity-related proteins, even in the absence of the pathogen or other pathogen-associated molecular patterns. This approach highlights the complementary nature of proteomics and metabolomics in studying effector-host interactions, and provides further support for the hypothesis that necrotrophic pathogens, such as S. nodorum, appear to exploit existing host cell death mechanisms to promote pathogen growth and cause disease. 相似文献
83.
近年来,常用未经丙酮固定的、由丁酸和巴豆油激活的B95-8细胞或P3HR-1细胞为靶细胞,检测人血清中EB病毒IgA/MA抗体以早期诊断鼻咽癌,效果良好。但由于B95-8细胞含有多种EB病毒抗原,不能用丙酮固定,需多次离心沉淀,在浮悬状态下检测,技术比较复杂。 相似文献
84.
双尾蚜属Diuraphis Aizenberg全世界记录13种,主要分布在古北界和新北界。根据种类丰富度和特有种成分,欧亚大陆的欧洲和中亚为该属蚜虫的现代第一分布中心,北美为第二分布中心。本文提供了该属所有13个种的分种检索表。双尾蚜属蚜虫在中国共有7种,主要分布在蒙新区。它们是:麦双尾蚜Diuraphis noxia (Mordvilko), 害冰麦双尾蚜D. nociva Zhang et Liang,冰草麦蚜D. (Holcaphis) agropyronophaga Zhang, 披碱草蚜D. (Holcaphis) elymophila Zhang, 西方麦蚜D. (Holcaphis) frequens (Walker), 雀麦蚜D. (Holcaphis) bromicola Hille Ris Lambers和绒毛草蚜D. (Holcaphis) holci (Hille Ris Lambers)。对中国种类进行了简要描述。 相似文献
85.
86.
Sun W Xing B Sun Y Du X Lu M Hao C Lu Z Mi W Wu S Wei H Gao X Zhu Y Jiang Y Qian X He F 《Molecular & cellular proteomics : MCP》2007,6(10):1798-1808
Hepatocellular carcinoma (HCC) is a highly malignant tumor, and chronic infection with hepatitis B virus is one of its major risk factors. To identify the proteins involved in HCC carcinogenesis, we used two-dimensional fluorescence DIGE to study the differentially expressed proteins in tumor and adjacent nontumor tissue samples. Samples from 12 hepatitis B virus-associated HCC patients were analyzed. A total of 61 spots were significantly up-regulated (ratio >/= 2, p = 0.01) in tumor samples, whereas 158 spots were down-regulated (ratio = -2, p = 0.01). Seventy-one gene products were identified among these spots. Members of the heat shock protein 70 and 90 families were simultaneously up-regulated, whereas metabolism-associated proteins were decreased in HCC samples. The down-regulation of mitochondrial and peroxisomal proteins in these results suggested loss of special organelle functions during HCC carcinogenesis. Four metabolic enzymes involved in the methylation cycle in the liver were down-regulated in HCC tissues, indicating S-adenosylmethionine deficiency in HCC. Two gene products, glyceraldehyde-3-phosphate dehydrogenase and formimidoyltransferase-cyclodeaminase, were identified from inversely altered spots, suggesting that different isoforms or post-translational modifications of these two proteins might play different roles in HCC. For the first time, the overexpression of Hcp70/Hsp90-organizing protein and heterogeneous nuclear ribonucleoproteins C1/C2 in HCC tissues was confirmed by Western blot and then by immunohistochemistry staining in 70 HCC samples, suggesting their potential as protein tumor markers. In summary, we profiled proteome alterations in HCC tissues, and these results may provide useful insights for understanding the mechanism involved in the process of HCC carcinogenesis. 相似文献
87.
Lanying Du Xiujuan Zhang Hong Yu Yusen Zhou Shibo Jiang 《Biochemical and biophysical research communications》2010,397(3):580-467
The worldwide outbreak of the swine-origin 2009 H1N1 influenza A virus (IAV) and an increasing number of influenza cases caused by a highly pathogenic avian influenza (HPAI) H5N1 have accelerated the need to develop vaccines and antiviral agents against IAVs. Among various antivirals, neutralizing monoclonal antibodies (mAbs) are considered important passive therapeutics having an immediate effect against viral pathogens. Here we report a pseudovirus neutralization assay for rapid screening of neutralizing mAbs targeting hemagglutinin (HA) of H5N1 and H1N1 IAV. In this study, we generated six pseudoviruses with an HIV-1 backbone, respectively, expressing HA of four clades of H5N1 IAV and the 2009 epidemic H1N1 IAV. The resulting pseudoviruses were able to infect a variety of human and non-human cells, with 293T cells from human kidney as the most susceptible target cells. Using the established pseudovirus neutralization assay, we showed that three of ten selected mAbs specific to HA could potently neutralize infection of a pseudovirus bearing HA from the homologous IAV A/VietNam/1194/2004(H5N1) strain. This was highly consistent with the result of a microneutralization assay testing the same strain of a live IAV. Since the pseudovirus neutralization assay does not involve an infectious virus and can be performed without the requirement of a biosafety-3 laboratory, it may be applied for safe and rapid screening of neutralizing mAbs and antiviral agents targeting HA of IAVs. 相似文献
88.
247例人乳头瘤病毒的PCR检测结果分析 总被引:1,自引:0,他引:1
247例生殖系分泌物标本用PCR检测人乳头瘤病毒HPV-DNA。结果显示:阳性感染率达87.6%,在与临床疾病密切的亚型中,6、11型感染率(60%),高于16、18型感染率(51.6%),但统计学处理没有显著性差异。女性发病率明显高于男性。易感人群组以20~40岁最高(占感染人数的84.4%),并且有年轻化的趋势(10~20岁年龄组占8.4%)。 相似文献
89.
植物钙/钙调素介导的信号转导系统 总被引:1,自引:0,他引:1
钙离子(Ca2+)是一种重要的第二信使, 参与调节植物的生长发育和对环境的适应。钙调素(CaM)和类钙调蛋白(CML)是一类最主要的Ca2+感受器, 虽然其自身没有催化活性, 但可通过调节下游靶蛋白的活性, 进而调控细胞的各种生理活动。该文总结了植物体内CaM结合蛋白(CBP)的生理功能、鉴定方法和调控机理, 以及CaM介导的信号转导途径, 包括蛋白磷酸化与去磷酸化、基因转录、离子运输、活性氧代谢、激素和磷脂信号等, 并对今后的研究方向进行了展望。 相似文献
90.
Hagen KD Hirakawa MP House SA Schwartz CL Pham JK Cipriano MJ De La Torre MJ Sek AC Du G Forsythe BM Dawson SC 《PLoS neglected tropical diseases》2011,5(12):e1442
Giardia intestinalis is a ubiquitous parasitic protist that is the causative agent of giardiasis, one of the most common protozoan diarrheal diseases in the world. Giardia trophozoites attach to the intestinal epithelium using a specialized and elaborate microtubule structure, the ventral disc. Surrounding the ventral disc is a less characterized putatively contractile structure, the lateral crest, which forms a continuous perimeter seal with the substrate. A better understanding of ventral disc and lateral crest structure, conformational dynamics, and biogenesis is critical for understanding the mechanism of giardial attachment to the host. To determine the components comprising the ventral disc and lateral crest, we used shotgun proteomics to identify proteins in a preparation of isolated ventral discs. Candidate disc-associated proteins, or DAPs, were GFP-tagged using a ligation-independent high-throughput cloning method. Based on disc localization, we identified eighteen novel DAPs, which more than doubles the number of known disc-associated proteins. Ten of the novel DAPs are associated with the lateral crest or outer edge of the disc, and are the first confirmed components of this structure. Using Fluorescence Recovery After Photobleaching (FRAP) with representative novel DAP::GFP strains we found that the newly identified DAPs tested did not recover after photobleaching and are therefore structural components of the ventral disc or lateral crest. Functional analyses of the novel DAPs will be central toward understanding the mechanism of ventral disc-mediated attachment and the mechanism of disc biogenesis during cell division. Since attachment of Giardia to the intestine via the ventral disc is essential for pathogenesis, it is possible that some proteins comprising the disc could be potential drug targets if their loss or disruption interfered with disc biogenesis or function, preventing attachment. 相似文献