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排序方式: 共有3745条查询结果,搜索用时 15 毫秒
41.
Melamed Barbara G.; Matthews Karen A.; Routh Donald K.; Stabler Brian 《Canadian Metallurgical Quarterly》1986,5(3):181
This article introduces the current issue of Health Psychology. The call for early intervention to prevent adulthood health problems and the need to consider each period of children's lives within its developmental perspective are the main emphases in this special issue of the journal. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
42.
In this work 23 month old rats were fed for 200 days with different protein diets (NT-diet: 19% protein, 72% of animal origin and LP-diet: 8.8% protein exclusively of vegetable origin). Some metabolic parameters and lifespan (on the base of a 50% death-rate) were determined. The relations of the liver free amino acids glycine + alanine and tyrosine + phenylalanine + branched chain amino acids and the ratio of phenylalanine/tyrosine were determined to be higher in the LP-group. Phenylalanine in liver and urea concentrations in liver and serum were lower in the LP-group. Furthermore the dopamine or serotonin levels were significantly lower in lateral and medial or lateral regions of the hypothalamus respectively in LP-diet fed rats. The norepinephrine content was not modified by the diets. The median lifespan of 23 month old rats was higher by 24% following LP-treatment. These results suggest that the protein component (amino acids) of different diets may modify metabolic parameters and lifespan of animals by mechanisms in which the central regulation may be involved. 相似文献
43.
Behaviors and emotions during specific visits may reveal the interpersonal processes of mother-daughter ties, yet most research uses global assessments of these ties. Forty-eight mother-daughter pairs participated in audiotaped conversations and completed surveys. All mothers were over age 70 and in good health. Daughters tended to take a central role in structuring the conversations. Conversations were characterized by high levels of felt and expressed positive emotions and behaviors for mothers and daughters. Nevertheless, mothers reported more positive and fewer negative emotions, whereas daughters expressed more positive behaviors than did mothers. Mothers' positive feelings and behaviors were associated with daughters'. Finally, mothers' and daughters' emotions and behaviors were associated with their destructive responses to being upset with each other, providing support for the ambivalence perspective of parent-offspring relationships. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
44.
Changes in and stability of hostility characteristics and their relationship to age, sex, and family support were examined among 108 10–18 yr olds in a 4-yr longitudinal study. Clinical ratings of Structured Interview potential for hostility, self-reported MMPI-derived hostile attitudes, and perceptions of family support were obtained at study entry and at follow-up when Ss were aged 15–21 yrs. Results showed relative stability of hostility rankings across 4 yrs, with males being more hostile than females. Both sexes increased in hostility over time, with the greatest increase in Ss who perceived low family support at follow-up and whose parents perceived high family support at study entry. Results are consistent with notions that early signs of hostility are risk factors for later development of coronary disease and that family environment influences development of hostility. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
45.
We present an analysis of a stochastic model of the vascular endothelial growth factor (VEGF) receptor. This analysis addresses the contribution of ligand-binding-induced oligomerization, activation of src-homology 2 domain-carrying kinases and receptor internalization in the overall behaviour of the VEGF/VEGF receptor (VEGFR) system. The analysis is based upon a generalization of a Wentzel-Kramers-Brillouin (WKB) approximation of the solution of the corresponding master equation. We predict that tumour-mediated overexpression of VEGFRs in the endothelial cells (ECs) of tumour-engulfed vessels leads to an increased sensitivity of the ECs to low concentrations of VEGF, thus endowing the tumour with increased resistance to anti-angiogenic treatment. 相似文献
46.
Paulo A. Santos Marcia A.S. Spinac Karen K.G. Fermoselli Marco-A. De Paoli 《Composites Part A》2007,38(12):2404-2411
The interest for the use of vegetal fibers as polymers reinforcement has recently increased because of their unique environmental and technological advantages. This work evaluated the use of Curauá fibers in polyamide-6 composites aiming at glass fiber replacement. Fiber content of 20, 30 or 40 wt% and fiber lengths of 0.1 or 10 mm were studied. Fibers were treated with N2 plasma or washed with NaOH solution, to improve their adhesion to PA-6. Samples with 20 wt% of short or long fibers, with or without pre-treatment, were compounded in two different co-rotating intermeshing twin-screw extruders. These samples were submitted to mechanical and thermal tests. In conclusion, non-dried raw materials improved fiber/matrix interfacial adhesion. Tensile and flexural properties of this composite are better than unfilled, but lower than glass fiber reinforced polyamide-6. However, its impact resistance and heat deflection temperature are similar to the glass fiber reinforced polyamide-6 and its lower density, enable it to replace this latter in specific non-critical applications. 相似文献
47.
48.
Expanded on R. E. Fassinger's (see record 1990-21225-001) model of career choice in college women by testing 2 causal models of career choice and orientation with high school women. Ss were 409 adolescent women enrolled in their last year of high school in an all-female private liberal arts high school in a large Midwestern city. Structural equation modeling analyses suggested that the career orientation and career choice of adolescent women were predicted by ability, agentic characteristics, gender role attitudes, and relationship with mother. Young women who possessed liberal gender role attitudes, were instrumental and efficacious with regard to math and careers, and exhibited moderate degrees of attachment and independence from their mothers tended to value their career pursuits. Adolescent women who selected nontraditional and prestigious careers showed high ability and strong agentic characteristics. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
49.
Abstract. Regional scientists have had a long fascination with spatial economic interdependence, initially stimulated by the development of a suite of models in Isard (1960). In recent years there have been two major developments; first, a movement towards greater integration in model development not only with large-scale models, but also with careful attempts to make more components of the system endogenous. The second development has been the pursuit of greater integration than in earlier studies between theory and applied regional economic modelling, most notably in the area of trade and economic development. We explore some of the recent developments of this latter approach and provide an assessment of the current state-of-the art of some future opportunities. 相似文献
50.
P Hamar V Müller M Kohnle O Witzke KH Albrecht T Philipp U Heemann 《Canadian Metallurgical Quarterly》1997,64(8):1135-1139
BACKGROUND: At the present time, late graft loss is the major cause of kidney failure after transplantation. However, the influence of metabolic factors on this process is ill-defined. METHODS: To identify the impact of lipid metabolism, glucose metabolism, and blood pressure and their prognostic value for graft survival, data for all recipients of a kidney allograft with a potential graft survival of >15 years and a minimum graft survival of 1 month were analyzed retrospectively. Recipients of kidney grafts functioning more than 15 years (n=32) were compared with those with a graft function of less than 10 years (n=152, controls) and evaluated in a multivariate analysis. RESULTS: Low levels of serum cholesterol, triglycerides, and glucose, before and after transplantation, were accompanied by a prolonged graft survival. Prognostic factors for early graft failure included serum triglycerides >300 mg/dl, cholesterol >250 mg/dl before transplantation, serum creatinine >4.0 mg/dl 1 month after transplantation, and donor age above 45 or less than 10 years. Additionally, systolic and, particularly, diastolic blood pressure was lower in the group with a prolonged graft function as compared with controls immediately before and after transplantation. In addition, the incidence of primary graft function was lower and the incidence of acute rejection episodes higher in controls. Cold and warm ischemic time, body mass index, recipient age, and gender did not differ significantly. CONCLUSIONS: Our data suggest that metabolic parameters play an important role in the process of late graft loss after kidney transplantation. 相似文献