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Parental monitoring, assessed as (perceived) parental knowledge of the child's behavior, has been established as a consistent predictor of problem behavior. However, recent research indicates that parental knowledge has more to do with adolescents' self-disclosure than with parents' active monitoring. Although these findings may suggest that parents exert little influence on adolescents' problem behavior, the authors argue that this conclusion is premature, because self-disclosure may in itself be influenced by parents' rearing style. This study (a) examined relations between parenting dimensions and self-disclosure and (b) compared 3 models describing the relations among parenting, self-disclosure, perceived parental knowledge, and problem behavior. Results in a sample of 10th- to 12th-grade students, their parents, and their peers demonstrated that high responsiveness, high behavioral control, and low psychological control are independent predictors of self-disclosure. In addition, structural equation modeling analyses demonstrated that parenting is both indirectly (through self-disclosure) and directly associated with perceived parental knowledge but is not directly related to problem behavior or affiliation with peers engaging in problem behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The authors of this study tested a selection–influence–de-selection model of depression. This model explains friendship influence processes (i.e., friends' depressive symptoms increase adolescents' depressive symptoms) while controlling for two processes: friendship selection (i.e., selection of friends with similar levels of depressive symptoms) and friendship de-selection (i.e., de-selection of friends with dissimilar levels of depressive symptoms). Further, this study is unique in that these processes were studied both inside and outside the school context. The authors used a social network approach to examine 5 annual measurements of data in a large (N =847) community-based network of adolescents and their friends (M = 14.3 years old at first measurement). Results supported the proposed model: adolescents tend to select friends with similar levels of depression, and friends may increase each other's depressive symptoms as relationships endure. These two processes were most salient outside the school context. At the same time, friendships seemed to be ended more frequently if adolescents' level of depressive symptoms was dissimilar to that of their friends. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Chagas disease is a neglected parasitic disease caused by the parasitic protozoan Trypanosoma cruzi and currently affects around 8 million people. Previously, 2-isopropyl-5-(4-methoxy-3-(pyridin-3-yl)phenyl)-4,4-dimethyl-2,4-dihydro-3H-pyrazol-3-one (NPD-0227) was discovered to be a sub-micromolar inhibitor (pIC50=6.4) of T. cruzi. So far, SAR investigations of this scaffold have focused on the alkoxy substituent, the pyrazolone nitrogen substituent and the aromatic substituent of the core phenylpyrazolone. In this study, modifications of the phenyldihydropyrazolone scaffold are described. Variations were introduced by installing different substituents on the phenyl core, modifying the geminal dimethyl and installing various bio-isosteres of the dihydropyrazolone group. The anti T. cruzi activity of NPD-0227 could not be surpassed as the most potent compounds show pIC50 values of around 6.3. However, valuable additional SAR data for this interesting scaffold was obtained, and the data suggest that a scaffold hop is feasible as the pyrazolone moiety can be replaced by a oxazole or oxadiazole with minimal loss of activity.  相似文献   
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Knowledge on lymph node metastases is crucial for the prognosis and treatment of prostate cancer patients. Conventional anatomic imaging often fails to differentiate benign from metastatic lymph nodes. Pelvic lymph node dissection is an invasive technique and underestimates the extent of lymph node metastases. Therefore, there is a need for more accurate non-invasive diagnostic techniques. Molecular and functional imaging has been subject of research for the last decades, in this respect. Therefore, in this article the value of imaging techniques to detect lymph node metastases is reviewed. These techniques include scintigraphy, sentinel node imaging, positron emission tomography/computed tomography (PET/CT), diffusion weighted magnetic resonance imaging (DWI MRI) and magnetic resonance lymphography (MRL). Knowledge on pathway and size of lymph node metastases has increased with molecular and functional imaging. Furthermore, improved detection and localization of lymph node metastases will enable (focal) treatment of the positive nodes only.  相似文献   
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The key pathogenic event in the onset of Alzheimer's disease (AD) is the aggregation of beta-amyloid (Abeta) peptides into toxic aggregates. Molecules that interfere with this process might act as therapeutic agents for the treatment of AD. The amino acid residues 16-20 (KLVFF) are known to be essential for the aggregation of Abeta. In this study, we have used a first-generation dendrimer as a scaffold for the multivalent display of the KLVFF peptide. The effect of four KLVFF peptides attached to the dendrimer (K(4)) on Abeta aggregation was compared to the effect of monomeric KLVFF (K(1)). Our data show that K(4) very effectively inhibits the aggregation of low-molecular-weight and protofibrillar Abeta(1-42) into fibrils, in a concentration-dependent manner, and much more potently than K(1). Moreover, we show that K(4) can lead to the disassembly of existing aggregates. Our data lead us to propose that conjugates that bear multiple copies of KLVFF might be useful as therapeutic agents for the treatment of Alzheimer's disease.  相似文献   
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The paper describes guidelines for building a finite element model of a unit cell of a textile made of superelastic NiTi wires and illustrates the application of the model for woven and knitted textiles. The goal of the analysis is prediction of the tensile diagram of the textile based on the fabric structure and the superelastic tensile diagram of the wires. The differences between the superelastic behaviour of the fabrics and that of individual wires are discussed. Predictions for a knitted NiTi fabric are compared with experimental data.  相似文献   
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