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排序方式: 共有1038条查询结果,搜索用时 31 毫秒
1.
Jun Ogata Kentaro Hirao Kenya Nishioka Arisa Hayashida Yuanzhe Li Hiroyo Yoshino Soichiro Shimizu Nobutaka Hattori Yuzuru Imai 《International journal of molecular sciences》2021,22(7)
Leucine-rich repeat kinase 2 (LRRK2) is a major causative gene of late-onset familial Parkinson’s disease (PD). The suppression of kinase activity is believed to confer neuroprotection, as most pathogenic variants of LRRK2 associated with PD exhibit increased kinase activity. We herein report a novel LRRK2 variant—p.G2294R—located in the WD40 domain, detected through targeted gene-panel screening in a patient with familial PD. The proband showed late-onset Parkinsonism with dysautonomia and a good response to levodopa, without cognitive decline or psychosis. Cultured cell experiments revealed that p.G2294R is highly destabilized at the protein level. The LRRK2 p.G2294R protein expression was upregulated in the patient’s peripheral blood lymphocytes. However, macrophages differentiated from the same peripheral blood showed decreased LRRK2 protein levels. Moreover, our experiment indicated reduced phagocytic activity in the pathogenic yeasts and α-synuclein fibrils. This PD case presents an example wherein the decrease in LRRK2 activity did not act in a neuroprotective manner. Further investigations are needed in order to elucidate the relationship between LRRK2 expression in the central nervous system and the pathogenesis caused by altered LRRK2 activity. 相似文献
2.
The performance of surface ionic conduction single chamber fuel cell (SIC‐SCFC) prepared by the sol gel method was studied on electric characteristics due to the differences of the operating temperature and humidity, the electrode distance and electrolyte film depth, and multiple cells with the series and parallel connections. The SIC–SCFC was arranged the both anode of Pt and cathode of Au on the boehmite electrolyte. The open circuit voltage (OCV) of single cell achieved a maximum of 530mV in the dry gas mixtures of O2/H2=50% in room temperature operation, and but it became decrease as over 60%. The OCV was maintained the constant value between operating temperatures of 30°C to 80°C, and but it was decreased sharply at over 90°C because a humidity on the cell became lower as increasing operating temperature. Then, the cell property was improved to 120°C by adding to the humidity of 70% using a humidifier. The electrode distance and the electrolyte film depth of SIC‐SCFC found to be contributed to the reductions of the cell resistance and the surface roughness on the electrode, respectively. Moreover, the power property of SIC‐SCFC was significantly improved by cell stacks comprised of the series or parallel connection of a cell. 相似文献
3.
In this article, we study a linear array of bowtie nanoantennas placed between two metallic strips that can work from 800 to 1420 nm (600 nm linewidth), with an electric field enhancement factor close to 20. We study the dynamical change of the position of the electric field enhancement amongst different elements in the array and, at the same time, the effects of dispersion on the scalability of the array elements. A systematic analysis and methodology to produce an array that can operate over a large bandwidth whilst maintaining the electric field enhancement without significant variation is provided. 相似文献
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Akiyoshi Wakatani 《Parallel Computing》2004,30(12):1345-1359
It is hard to implement the ADI method in an efficient way on distributed-memory parallel computers. We propose “P-scheme” which parallelizes a tridiagonal linear system of equations for the ADI method, but its effectiveness is limited to the cases where the problem size is large enough mainly because of the communication cost of the propagation phase of the scheme.
In order to overcome this difficulty, we propose an improved version of the P-scheme with “message vectorization” which aggregates several communication messages into one and alleviates the communication cost. Also we evaluate the effectiveness of message vectorization for the ADI method and show that the improved version of the P-scheme works well even for smaller problems and linear and super-linear speedups can be achieved for 8194 × 8194 and 16,386 × 16,386 problems, respectively. 相似文献
6.
The very late antigen-4 (VLA-4) integrin expressed on the surface of lymphocytes and macrophages can regulate their migration to inflammatory sites as well as control cellular activation. The role of VLA-4 in the establishment of autoimmune diabetes is not easily predicted given the multiplicity of adhesion pathways and their differential use by various cell types. The contribution of VLA-4 to insulin-dependent diabetes mellitus was investigated by administration of VLA-4-specific monoclonal antibodies (MoAb) in an adoptive transfer model of disease in NOD mice. This study shows that VLA-4-specific MoAbs profoundly inhibit the development of diabetes with protection sustained by repeated MoAb exposure. Insulitis was completely inhibited during treatment and progressed to a severe degree once MoAb treatment was suspended, yet approximately 40% of treated recipients failed to become diabetic during 1-2 months post-treatment. Although we cannot rule out depletion of a relatively minor subpopulation of cells by prolonged anti-VLA-4 MoAb exposure, this inhibition of diabetes onset by treatment with MoAbs to VLA-4 supports a dependence on VLA-4 for cellular functions leading to diabetes and demonstrates that a significant disease modifying effect can be mediated by targeting the VLA-4 integrin. 相似文献
7.
Tests and theoretical analysis on the maximum strength of high strength bolted tension flanges joining square hollow section members have been carried out. Yield line theory has been applied in a similar way to that presented in a previous paper. Correlation between test results and theoretical predictions is quite satisfactory. Based on this study, a simple design formula has been proposed. 相似文献
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9.
氧浓度对近临界水中纤维素分解的影响 总被引:3,自引:0,他引:3
研究了不同初始氧浓度对纤维素在近临界水中分解的影响,实验结果表明,氧浓度显著地影响产物总碳收支平衡,液相不同组分的收率、气体的产量以及气相产物的组成,微量氧对产物总碳收支平衡影响不大,而对液相不同组分的收率有一定的影响。从实验结果可以看出,离子型反应机理在纤维素水解的第一步中起主导作用。而单糖的进一步分解是一个以自由基反应机理为主的过程。 相似文献
10.