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51.
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
52.
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
53.
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
54.
About Sulfur Containing Glycosides of Rape Seeds – Analysis by Thermospray Technique/Mass Spectrometry The HPLC is the method of choise for the estimation of glucosinolates occurring in rape seeds. But in comparison to GC a disadvantage is that the HPLC fractions can't be analyzed by MS directly. Such possibility is opened now with the thermospray technique. It allows to introduce the HPLC fractions immediately into the mass spectrometer system. Based on the first application of this technique to glucosinolates published by Mellon et al. (1987) the fundamentals of the thermospray technique/mass spectrometry are presented, the experimental details are explained and the characteristic ions of the thermospray mass spectra of 12 glucosinolates (desulfo derivatives) are discussed. The analytical performance of the method is examined also. 相似文献
55.
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
56.
In this article, results are presented of annual simulations of a decentralized (regional) plant for the power and heat supply of a residential complex. This complex consists of four houses with 40 flats all in all. The annual power consumption of the complex is 157 MWh and the heat requirement is 325 MWh. The concrete dynamics of the energy demands over the year is taken into consideration. The energy supply system is composed of a power-controlled combined heat and power (CHP) plant (55 kW), a photovoltaic plant (PV array or PV plant) array for power generation as well as a field of solar thermal collectors with a short-term accumulator for water heating and a long-term accumulator for supplying heat for domestic heating purposes. Simulation results demonstrate that synergetic effects result from the combination of a CHP plant with wind power and PV plants of varying sizes, which have an effect on the cost effectiveness of the plant as a whole with the different dynamics of energy sources (wind and solar energies) and of the consumption of power and heat being the decisive factors. The power deficits of wind power and PV plants are compensated through the application of a natural gas-operated CHP plant. In almost all variants, the demand for fossil energy carriers is distinctly less than in conventional energy supply plants. 相似文献
57.
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
58.
LE Philpotts CH Lee BG Haffty RC Lange I Tocino 《Canadian Metallurgical Quarterly》1996,201(3):767-771
PURPOSE: To compare the mammographic findings of recurrent breast cancer with those of the primary tumor in patients who underwent lumpectomy and radiation therapy. MATERIALS AND METHODS: Mammograms were reviewed of primary and recurrent tumors in 25 patients (26 lesions). Mammographic appearance, location, and histopathologic characteristics were retrospectively compared between primary and recurrent tumors. RESULTS: Primary and recurrent tumors were mammographically similar in 21 (81%) of the 26 lesions. Of 14 primary tumors with calcifications, 12 (86%) recurred with calcifications, and of the 12 masses, nine (75%) recurred as masses. Recurrent tumors that occurred in the lumpectomy quadrant were more often similar in mammographic appearance to the primary tumor (20 of 22 tumors) than those in other quadrants (one of four tumors) (P < .02). CONCLUSION: After conservative treatment of breast cancer, the majority of recurrent tumors appear to be mammographically similar to primary tumors. It is prudent to review preoperative mammograms during follow-up of patients after lumpectomy and radiation therapy. 相似文献
59.
MK Lange A Sandhu J Sampsel G Hinkle J Ignaszewski E Martin P Sandhu EW Martin 《Canadian Metallurgical Quarterly》1993,55(2):205-213
1. The effects of diethyl maleate (DEM) on the cytotoxicity of phenyl-hydroquinone (PHQ) and other hydroquinones were studied in freshly isolated rat hepatocytes. 2. Addition of PHQ (0.5 or 0.75 mM) to hepatocytes resulted in dose-dependent cell death accompanied by the abrupt depletion of both GSH and protein thiols and the accumulation of phenyl-benzoquinone (PBQ). 3. Pretreatment with DEM (1.25 mM), which causes an abrupt depletion of cellular GSH in hepatocytes, delayed the onset of PHQ-induced cytotoxicity. The delay correlated with inhibition of PBQ formation. 4. Although the pH of the cell suspension was increased slightly (mean pH 0.18) by incubation under carbogen flow, the addition of DEM to the cell suspension inhibited both the increase in pH and the formation of PBQ from PHQ. 5. In hepatocyte suspensions without DEM, PHQ cytotoxicity was dependent on pH, and toxicity was associated with oxidation of PHQ and accumulation of PBQ. 6. Among other hydroquinones (0.5 mM), tert-butyl-hydroquinone-induced cytotoxicity was decreased by DEM (1.25 mM), but DEM did not affect the cytotoxicity of 2,5-di(tert-butyl)-1,4-benzohydroquinone. 7. PHQ-induced cytotoxicity correlated with the accumulation of PBQ in the cell, and the inhibition of PHQ-induced cytotoxicity by DEM correlated with pH-dependent changes in PBQ formation. 相似文献
60.