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排序方式: 共有1422条查询结果,搜索用时 31 毫秒
1.
Daniel H. Stones Anne-Marie Krachler 《International journal of molecular sciences》2015,16(2):2626-2640
The ability of bacterial species to colonize and infect host organisms is critically dependent upon their capacity to adhere to cellular surfaces of the host. Adherence to cell surfaces is known to be essential for the activation and delivery of certain virulence factors, but can also directly affect host cell signaling to aid bacterial spread and survival. In this review we will discuss the recent advances in the field of bacterial adhesion, how we are beginning to unravel the effects adhesins have on host cell signaling, and how these changes aid the bacteria in terms of their survival and evasion of immune responses. Finally, we will highlight how the exploitation of bacterial adhesins may provide new therapeutic avenues for the treatment of a wide range of bacterial infections. 相似文献
2.
相干源二维波达方向估计 总被引:4,自引:0,他引:4
本文分析了平面阵接收信号的协方差矩阵,发现它可分解为一个广义对称矩阵与一个非广义对称矩阵之和,利用信号协方差矩阵的这一结构特征,重点研究了相干源二维波达方向(DOA)估计.该方法通过构造一个差矩阵,求出其本特征值对应的任一特征向量,利用谱函数估计相干源二维DOA.简要分析了二维DOA估计的分维处理。 相似文献
3.
A. Aryshev S. Araki P. Karataev T. Naito N. Terunuma J. Urakawa 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2007,580(3):1544-1551
A fast room temperature microwave detection system based on the Schottky Barrier-diode detector was created at the KEK ATF (Accelerator Test Facility). It was tested using Coherent Synchrotron Radiation (CSR) generated by the 1.28 GeV electron beam in the damping ring. The speed performance of the detection system was checked by observing the CSR from a multi-bunch (2.8 ns bunch separation time) beam. The theoretical estimations of CSR power yield from an edge of bending magnet as well as new injection tuning method are presented. A very high sensitivity of CSR power yield to the longitudinal electron distribution in a bunch is discussed. 相似文献
4.
5.
Tokar David M.; Withrow Jason R.; Hall Rosalie J.; Moradi Bonnie 《Canadian Metallurgical Quarterly》2003,50(1):3
Structural equation modeling was used to test theoretically based models in which psychological separation and attachment security variables were related to career indecision and those relations were mediated through vocational self-concept crystallization. In contrast to previous studies, which have found either weak or no support for a relation between separation or attachment security variables and career indecision, results based on a sample of 350 college students indicated that some components of separation and attachment security did relate to career indecision in a theoretically supportable direction. Results also revealed that regardless of whether global or component career indecision measures were used, separation and attachment security effects on indecision were at least partially mediated through vocational self-concept crystallization. The strongest mediated relations were observed for the effects of attachment anxiety and maternal separation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
6.
Children's perceived attachments with parents, and family cohesion and adaptability were examined as predictors, mediators, and moderators in the parental problem drinking-child outcomes link. A total of 216 6- to 12-year-olds (110 boys, 106 girls) participated. Data were obtained from children and their mothers, fathers, and teachers. A higher level of family cohesion and adaptability functioned as (a) a robust protective factor against adjustment and cognitive difficulties otherwise associated with problem drinking and (b) a mediator of adjustment problems. Children's perceptions of attachments to mothers and fathers were consistent predictors of behavioral, social, and cognitive problems and further moderated relations between problem drinking and child functioning. The results support that child-parent and family functioning variables act as either pathways and/or vulnerability and protective factors for children exposed to a high-risk environment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
7.
This study examines the ways in which therapists function as attachment figures for patients. Patients in long-term psychoanalytic therapy answered questionnaires about their feelings about their therapists and their closest personal relationships. Components of attachment prominent in the therapeutic relationships were looking up to the therapist and feeling the therapist was responsive to emotional needs. Stronger attachment to therapists was associated with greater frequency and duration of therapy, a stronger working alliance, and greater security of the patients' attachment style, as well as with the gender of the patient and therapist. Using attachment theory to understand psychoanalytic relationships emphasizes the unique importance of a therapist to a patient and can offer new perspectives on both therapeutic and attachment processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
8.
强度型光纤传感器的信号检测系统 总被引:1,自引:0,他引:1
余向东 《中国计量学院学报》1996,(1)
本文阐述了一种可提高强度型光纤传感器测量精度的检测系统。该系统利用同一检测电路交替检测信号、参考通道的输出信号,并将信号、参考两通道的检测结果相除,从而消除了因发光二极管光源波动及检测电路系统不稳定所带来的误差。采用同步相关技术抑制了噪声,提高了输出信噪比。实验证明,当时间常数RC为0.05S时,采用该检测系统可获得优于千分之一的零点稳定性和优于2×103的输出信噪比。 相似文献
9.
Little is known about whether personality characteristics influence initial attraction. Because adult attachment differences influence a broad range of relationship processes, the authors examined their role in 3 experimental attraction studies. The authors tested four major attraction hypotheses--self similarity, ideal-self similarity, complementarity, and attachment security--and examined both actual and perceptual factors. Replicated analyses across samples, designs, and manipulations showed that actual security and self similarity predicted attraction. With regard to perceptual factors, ideal similarity, self similarity, and security all were significant predictors. Whereas perceptual ideal and self similarity had incremental predictive power, perceptual security's effects were subsumed by perceptual ideal similarity. Perceptual self similarity fully mediated actual attachment similarity effects, whereas ideal similarity was only a partial mediator. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
10.
Lopez Frederick G.; Fons-Scheyd Alia; Morúa Wendy; Chaliman Rebecca 《Canadian Metallurgical Quarterly》2006,53(4):543
This study examined the nature and impact of dyadic perfectionism over a 3-month interval within a sample of 116 college students who were currently involved in an intimate heterosexual relationship. Dyadic perfectionism scores were stable and correlated as expected with scores on concurrent measures of adult attachment orientations and relationship satisfaction. Logistic regression analyses revealed that, controlling for initial commitment status and adult attachment orientations, Time 1 dyadic perfectionism scores significantly and uniquely predicted relationship continuity 3 months later. Lastly, controlling for social desirability, relationship commitment status, and Time 1 adult attachment orientation scores, Time 1 dyadic perfectionism scores also uniquely predicted Time 2 relationship distress. Findings provide additional evidence that dyadic perfectionism is a risk factor for relationship dysfunction. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献