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1.
Early patterning of prelimbic cortical axons to the striatal patch compartment in the neonatal mouse
LK Nisenbaum SM Webster SL Chang KD McQueeney JJ LoTurco 《Canadian Metallurgical Quarterly》1998,20(2-3):113-124
The striatum receives excitatory input from virtually the entire cerebral cortex. In the adult, this input is segregated into two functionally distinct compartments of the striatum, the patch (striosome) and matrix regions. This study determined whether the patterning of corticostriatal afferents from the prelimbic cortex to the striatal patch compartment develops during the early period of collateral formation or instead at the time of peak synaptogenesis. Initial formation of corticostriatal axon collaterals was observed by embryonic day (E) 19. Quantification of corticostriatal collaterals revealed a significant increase in the number and complexity of collateral branches at postnatal day 6 as compared to E19. Concomitant with the increase in collateral branching, a heterogeneous pattern of collateralization consisting of parallel rows of corticostriatal collaterals was observed in the medial striatum. In addition to the rows, clusters of corticostriatal axons occurred more laterally. These clusters colocalized with patches of dense tyrosine hydroxylase-positive fibers, a marker for the striatal patch compartment in the neonatal mouse. Together, these data indicate that corticostriatal patterning occurs during the period of early axon collateralization resulting in a segregation of corticostriatal axon collaterals from the prelimbic cortex to the striatal patch compartment. 相似文献
2.
Less may not be more,but it still counts: The state of social capital in Yeoville,Johannesburg 总被引:2,自引:2,他引:0
Kirsten Harrison 《Urban Forum》2002,13(1):67-84
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This study used a pretest-posttest preexperimental design to examine the effect of a 10-week behavioral medicine support group intervention in a sample of persons with HIV. Using Solomon's psychoneuroimmunologic framework, the 10-week behavioral medicine program focused on the mind/body interaction, the relaxation response, coping with illness, hardiness, and nutrition. Pearson correlation coefficients and t tests were performed on the pre- and postintervention measures of hardiness, social support, immune function, and perceived health status. Results of the study indicated that hardiness (preintervention) and CD4 counts (pre- and postintervention) were significantly correlated with health status; however, CD4 counts decreased over the course of the behavioral medicine program. Implications for nursing and recommendations for further research are discussed. 相似文献
5.
Chapman Derek S.; Uggerslev Krista L.; Webster Jane 《Canadian Metallurgical Quarterly》2003,88(5):944
This field study examined applicant reactions (N = 802) toward face-to-face as compared with technology-mediated interviews (through videoconferencing or by telephone) for 346 organizations. Face-to-face interviews were perceived as more fair and led to higher job acceptance intentions than were videoconferencing and telephone interviews. Perceived interview outcomes were higher with face-to-face and telephone interviews over videoconferencing. Self-monitoring moderated the relationship between interview medium and perceptions of fairness. Specifically, this relationship was (a) positive for face-to-face, (b) negative for telephone, and (c) nonsignificant for videoconferencing interviews. Moreover, the number of offers an applicant received moderated the relationship between interview medium over, and perceived fairness. The relationship between number of offers and perceived fairness was positive for face-to-face and negative for technology-mediated interviews. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
6.
Kessler Ronald C.; Foster Cindy; Webster Pamela S.; House James S. 《Canadian Metallurgical Quarterly》1992,7(1):119
There is inconsistency in the literature on the relationship between age and depressive symptoms. Although a careful review shows that some of this inconsistency can be reconciled by recognizing the nonlinear relationship (J. P. Newmann, 1989), 2 additional issues remain unclear. One is that most previous studies used depression screening scales that contain somatic items that could introduce an age bias. The other is that most previous studies combined samples of men and women even though there is evidence that the sex difference in depressive symptoms varies with age. These 2 issues are addressed in this article, using analyzed data from 2 large national surveys. There is a consistent, but quite modest, nonlinear association between age, somatic, and nonsomatic depressive symptoms in both surveys. There is no significant sex difference in the age curves. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
7.
Oxidation protection for carbon fibre composites 总被引:7,自引:0,他引:7
M. E. Westwood J. D. Webster R. J. Day F. H. Hayes R. Taylor 《Journal of Materials Science》1996,31(6):1389-1397
Carbon fibre-reinforced ceramic matrix composites are promising candidate materials for high-temperature structural applications such as gas turbine blades. In oxidizing environments at temperatures above 400°C, however, carbon fibres are rapidly oxidized. There is, therefore, a need to coat the composite in order to protect it against oxidation. This review identifies the requirements of an effective oxidation protection system for carbon fibre-reinforced ceramics and summarizes the work which has been carried out towards this goal over the last 50 years. The most promising coatings are those composed of several ceramic layers designed to protect against erosion, spallation and corrosion, in addition to possessing a self-healing capability by the formation of glassy phases on exposure to oxygen. 相似文献
8.
Describing and predicting alcohol use-related harm: an analysis of the Yukon Alcohol and Drug Survey
During 1990 the Yukon Bureau of Statistics conducted an alcohol and drug survey with a sample of 1,348 residents of the Territory, aged 15 and over. Over three-quarters of the sample reported experiencing at least one type of harm from others' drinking during the past year, and over a half experienced two or more types of harm. Among the main predictors of prevalence and extent of harm were respondents' age (younger), a greater number of drinks per occasion, close associates with alcohol problems, and residing in smaller communities. The results are discussed in terms of their relevance to identifying vulnerable groups and informing policy aimed at reducing alcohol use-related harm. 相似文献
9.
Ben-Porath Yossef S.; Hostetler Kirsten; Butcher James N.; Graham John R. 《Canadian Metallurgical Quarterly》1989,1(3):169
The development of three new content-homogeneous subscales for the revised Minnesota Multiphasic Personality Inventory (MMPI-2; J. N. Butcher et al, 1989) Social Introversion (Si) scale designed to replace the K. Serkownek (1975) subscales, which were not included in the revised MMPI, is described. The subscales, termed Shyness/Self-Consciousness, Social Avoidance, and Self/Other Alienation, were developed with data provided by college students (515 men and 797 women). Data analyses with this and the MMPI-2 normative sample demonstrated that the new subscales independently contribute to the assessment of nearly 90% of the variance in the full Si scale, that they display both convergent and divergent validity, and that these attributes generalize beyond the sample with which they were developed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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