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1.
Plant Molecular Biology -  相似文献   
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水稻对褐飞虱抗性相关蛋白的双向电泳分析   总被引:13,自引:0,他引:13  
以药用野生稻 (Oryzaofficinalis)的转育后代B5 (高抗褐飞虱 (NilaparvatalugensSt l) )与感虫品种明恢 6 3(OryzasativaL .)为亲本 ,构建了一个重组自交系群体。通过抗褐飞虱鉴定 ,筛选出极端抗虫株系和极端感虫株系 ,运用分群分析法 (bulkedsegregantanalysis ,BSA)分别建成了极端抗虫集团 (resistantbulk)和极端感虫集团 (susceptiblebulk)的蛋白质池。利用双向电泳技术 ,分别分析了极端抗虫集团和极端感虫集团受虫害与未受虫害的秧苗蛋白质的变化。结果发现 ,虫害 48h后 ,感虫集团的一个分子量为 40kD的蛋白质P40 (pI=6 .3)的表达明显减弱甚至消失 ,而在抗虫集团中 ,P40的表达未受影响。与褐飞虱为害后抗虫株系和感虫株系不同的生理反应相联系 ,推测P40与水稻受褐飞虱虫害后引起的应答反应相关  相似文献   
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曾力宇  金奇 《病毒学报》1997,13(4):351-356
从中国发病鸡群中分离的鸡减蛋综合征病毒弱毒株AA-2,经常规方法提取其病毒核酸后,组建了完整的限制性内切酶PstI及HingⅢ水解片段的基因文库,并对其中HindⅢ,-SacⅠ进行了序列测定。同源比较分析证明:其L链含编码病毒末端前体蛋白,容量为580个氨基酸残基的开放读码框架。  相似文献   
6.
Gao  Lei  Yuan  Zihao  Li  Yunfeng  Ma  Zhen 《Functional & integrative genomics》2022,22(3):317-330
Functional & Integrative Genomics - DNAJ proteins function as co-chaperones of HSP70 and play key roles in cell physiology to promote protein folding and degradation, especially under...  相似文献   
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Chemical proteomics is an emerging technique for drug target deconvolution and profiling the toxicity of known drugs. With the use of this technique, the specificity of a small molecule inhibitor toward its potential targets can be characterized and information thus obtained can be used in optimizing lead compounds. Most commonly, small molecules are immobilized on solid supports and used as affinity chromatography resins to bind targets. However, it is difficult to evaluate the effect of immobilization on the affinity of the compounds to their targets. Here, we describe the development and application of a soluble probe where a small molecule was coupled with a peptide epitope which was used to affinity isolate binding proteins from cell lysate. The soluble probe allowed direct verification that the compound after coupling with peptide epitope retained its binding characteristics. The PKC-alpha inhibitor Bisindolylmaleimide-III was coupled with a peptide containing the FLAG epitope. Following incubation with cellular lysates, the compound and associated proteins were affinity isolated using anti-FLAG antibody beads. Using this approach, we identified the known Bisindolylmaleimide-III targets, PKC-alpha, GSK3-beta, CaMKII, adenosine kinase, CDK2, and quinine reductase type 2, as well as previously unidentified targets PKAC-alpha, prohibitin, VDAC and heme binding proteins. This method was directly compared to the solid-phase method (small molecule was immobilized to a solid support) providing an orthogonal strategy to aid in target deconvolution and help to eliminate false positives originating from nonspecific binding of the proteins to the matrix.  相似文献   
8.
广东省曲江县发现鳄蜥   总被引:5,自引:2,他引:5  
报道了首次发现于广东的鳄蜥的形态结构特征,并将它与广西的鳄蜥进行了比较。  相似文献   
9.

Background

Migration is a major challenge to tuberculosis (TB) control worldwide. TB treatment requires multiple drugs for at least six months. Some TB patients default before completing their treatment regimen, which can lead to ongoing infectiousness and drug resistance.

Methods

We conducted a retrospective analysis of 29,943 active TB cases among urban migrants that were reported between 2000 to 2008 in Shanghai, China. We used logistic regression models to identify factors independently associated with treatment defaults in TB patients among urban migrants during 2005-2008.

Results

Fifty-two percent of the total TB patients reported in Shanghai during the study period were among urban migrants. Three factors increased the odds of a treatment default: case management using self-administered therapy (OR, 5.84, 95% CI, 3.14-10.86, p<0.0005), being a retreatment case (OR, 1.47, 95% CI, 1.25-1.71, p<0.0005), and age >60 years old (OR, 1.33, 95% CI, 1.05-1.67, p=0.017). The presence of a cavity in the initial chest radiograph decreased the odds for a treatment default (OR, 0.87, 95% CI, 0.77-0.97, p=0.015), as did migration from central China (OR, 0.85, 95% CI, 0.73-0.99, p=0.042), case management by family members (OR, 0.73, 95% CI 0.66-0.81, p<0.0005), and the combination of case detection by a required physical exam and case management by health care staff (OR, 0.64, 95% CI, 0.45-0.93, p=0.019).

Conclusion

Among TB patients who were urban migrants in Shanghai, case management using self-administered therapy was the strongest modifiable risk factor that was independently associated with treatment defaults. Interventions that target retreated TB cases could also reduce treatment defaults among urban migrants. Health departments should develop effective measures to prevent treatment defaults among urban migrants, to ensure completion of therapy among urban migrants who move between cities and provinces, and to improve reporting of treatment outcomes.  相似文献   
10.
The eruciform larvae of holometabolous insects are primarily characterized by bearing a varying number of abdominal prolegs in addition to three pairs of thoracic legs. However, whether the prolegs are evolutionarily homologous among different insect orders is still a disputable issue. We examined the embryonic features and histological structure of the prolegs of the scorpionfly Panorpa byersi Hua and Huang (Mecoptera: Panorpidae) and the Oriental armyworm Mythimna separata (Walker) (Lepidoptera: Noctuidae) to investigate whether the prolegs are homologous between these two holometabolous insect orders. In the scorpionfly, paired lateral process primordia arise on abdominal segments I–VIII (A1–A8) in line with the thoracic legs in early embryonic stages, but degenerate into triangular protuberances in later stages, and paired medial processes appear along the midventral line before dorsal closure and eventually develop into unjointed, cone‐shaped prolegs. Histological observation showed that the lumina of the prolegs are not continuous with the hemocoel, differing distinctly from that of the basic appendicular plan of thoracic legs. These results suggest that the prolegs are likely secondary outgrowths in Mecoptera. In the armyworm, lateral process primordia appear on A1–A10 in alignment with the thoracic legs in the early embryonic stages, although only the rudiments on A3–A6 and A10 develop into segmented prolegs with the lumina continuous with the hemocoel and others degenerate eventually, suggesting that the prolegs are true segmental appendages serially homologous with the thoracic legs in Lepidoptera. Therefore, we conclude that the larval prolegs are likely not evolutionarily homologous between Mecoptera and Lepidoptera. J. Morphol. 277:585–593, 2016. © 2016 Wiley Periodicals, Inc.  相似文献   
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