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1.
A review of the literature on the impact of sexual contacts between adults and boys reveals the existence of two principal outcomes: 1) some participants develop various disorders once in adulthood, such as behavioural problems, sexual disorders, or personality problems; 2) some participants do not present with any major disorders in the long run. These different outcomes may be associated with several moderating variables related to the sexual contacts, such as the level of coercion at the time of these contacts, the bond between the child and the adult, or the context of the sexual relation. However, the conclusions relating to the relations between early sexual contacts with adults and subsequent problems of adaptation in adulthood are difficult to determine. This is because of various methodological problems associated with relevant studies (i.e., definition of these contacts, nature of the sample, method evaluation, statistical analyses). In this article, we propose certain avenues of research that may help clarify this problem. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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S Chasserot-Golaz P Hubert D Thiersé S Dirrig CJ Vlahos D Aunis MF Bader 《Canadian Metallurgical Quarterly》1998,70(6):2347-2356
Several lines of evidence suggest that phosphorylated products of phosphatidylinositol play critical functions in the regulation of membrane trafficking along the secretory pathway. To probe the possible involvement of phosphatidylinositol 3-kinase (PI 3-kinase) in regulated exocytosis, we have examined its subcellular distribution in cultured chromaffin cells by immunoreplica analysis and confocal immunofluorescence. We found that the PI 3-kinase heterodimer consisting of the regulatory and catalytic subunits was associated essentially with the subplasmalemmal cytoskeleton in both resting and nicotine-stimulated chromaffin cells. Attempts to immunoprecipitate PI 3-kinase with anti-phosphotyrosine antibodies failed, suggesting that the activity of PI 3-kinase was not modulated by tyrosine phosphorylation and/or physical interaction with SH2-containing proteins in stimulated chromaffin cells. LY294002 [2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one], a potent inhibitor of PI 3-kinase, produced a dose-dependent inhibition of catecholamine secretion evoked by various secretagogues. Furthermore, cytochemical experiments with rhodamine-labeled phalloidin revealed that LY294002 blocked the disassembly of cortical actin in chromaffin cells stimulated by a depolarizing concentration of potassium. Our results suggest that PI 3-kinase may be one of the important regulatory exocytotic components involved in the signaling cascade controlling actin rearrangements required for catecholamine secretion. 相似文献
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V Blanc P Gil N Bamas-Jacques S Lorenzon M Zagorec J Schleuniger D Bisch F Blanche L Debussche J Crouzet D Thibaut 《Canadian Metallurgical Quarterly》1997,23(2):191-202
Dextran has been used as a carrier molecule for the synthesis of monofunctional peptide-dextran conjugates. The immunodetection of such carrier immobilized peptides on ELISA plates was compared to that of peptides adsorbed directly to immunoplates. The main features observed with peptide-dextran conjugates were as follows: only small amounts of peptide (1-2 mg) were necessary for coupling via alpha- or epsilon-amino groups to NaIO4-activated dextran (4 mg); the coupling yield was up to 68%; an amino acid analysis of the conjugate enabled the amount of carrier immobilized peptide to be calculated; an estimated 15-17 peptides were bound per dextran molecule (MW 73,500); using a carbohydrate as carrier reduces the possibility of non-specific interactions because no hydrophobic or ionic sites and no protein-like epitopes exist on the carrier apart from the peptide ligand. It can be assumed that some peptide ligands provide the forces for an interaction with the plate surface whereas other remain free for the interaction with the antibody. Thus, the detection with monoclonal anti-peptide antibodies allowed peptide-dextran conjugates to be used at coating concentrations of 1-3 nM peptide, corresponding to 0.6-2.6 ng peptide-dextran per well. In contrast, concentrations of 150-500 nM were required for coating with peptides. The applicability of monofunctional peptide-dextran conjugates was demonstrated by investigating the titer and specificity of a polyclonal anti-peptide serum developed against human gastrointestinal glutathione peroxidase. The introduction of biotin as a second ligand of the dextran conjugate permitted its capture on streptavidin coated plates. This synthesis of bifunctional peptide-biotin-dextran conjugates opens up additional possibilities for applications. 相似文献
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A necessary and sufficient condition is given for a connected bipartite graph to be the incidence graph of a contact family
of segments and points. We deduce that any four-connected three-colorable plane graph is the contact graph of a family of
segments and that any four-colored planar graph without an induced C4 using four colors is the intersection graph of a family of straight line segments. 相似文献
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An axisymmetrical model of a rapid nonisobaric heavily laden gas‐particle jet is developed. The model is based on the general functions for both axial and radial pressure distributions, which were discovered by a numerical study of rapid gas‐particle jets by the CFD code. The model equations were solved analytically. The results obtained by the model developed are in good agreement with those computed by the CFD code for a wide range of flow parameters. 相似文献
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H Laurichesse M Cambon D Perre T Ancelle M Mora B Hubert J Beytout M Rey 《Canadian Metallurgical Quarterly》1997,7(5):R69-R73
The investigation of a trichinosis outbreak in Auvergne, France identified 23 cases in 12 households living in two cities-Clermont-Ferrand and Montlu?on-between 15 February and 7 March 1991. One patient required intensive care, 15 had major symptoms, and seven had minor or no symptoms. Two case control studies demonstrated a significant (p < 0.01) association between eating horse meat and acute trichinosis. Veterinary services found that three supermarkets where the patients had bought horse meat during the suspected period had been supplied by a single wholesaler. The analysis of the wholesaler's records revealed that the implicated horse meat had been imported from a slaughterhouse in the United States. This outbreak occurred despite a requirement in France for all meat from horses slaughtered in France and in countries exporting meat to France to be examined systematically for trichinella. 相似文献
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