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91.
Announces the death of C. W. Thomas II, former professor of Urban Studies and Planning at the University of California, San Diego and a fellow of the American Psychological Association. Thomas, a psychologist, researched issues on vocational rehabilitation and the importance of racial factors in human interactions. Thomas emphasized the importance of understanding the effects of racism in therapeutic approaches with African Americans. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
92.
Human neutrophil PLD activity stimulated with GTP-gamma-S was reconstituted with recombinant ARF1 in cytosol-depleted cells. PMA-pretreatment of intact cells greatly enhanced the subsequent reconstitution of the ARF1-regulated PLD activity. This enhancement was only observed provided that the intact cells were pretreated with PMA, suggesting the stable recruitment of a cytosolic component, presumably protein kinase C, to the membranes. rARF1-reconstituted PLD activity was not dependent on MgATP, but could be considerably enhanced by MgATP. Maximal effects of MgATP were seen at 1 mM. This enhancement by MgATP could not be attributed to protein kinase C. Neomycin was found to inhibit ARF1-regulated PLD activity suggesting the requirement for polyphosphoinositides. We conclude: (i) that many of the observed effects of PMA may be dependent on the presence of the small GTP-binding protein, ARF, and (ii) polyphosphoinositides are required for ARF1-stimulated PLD activity.  相似文献   
93.
Analysis of recent data reported in the literature on low temperature swelling and densification behavior of light water reactor (LWR) fuel suggests that, at low irradiation temperatures, the extent of irradiation induced densification shows a simple exponential dependence on burnup with a rate constant that is insensitive to temperature and flux level. These data are also consistent with the view that the total porosity controls the kinetics of irradiation-induced densification process. In the same temperature range the rate of swelling was found to be constant to a burnup near 50 GWD/MTU, with a value of approximately 1% per 10 GWD/MTU. The significance of these results is discussed in terms of current theories.  相似文献   
94.
A hazard of regional perfusion for melanoma is incomplete isolation, resulting in leakage of the cytostatic drug into the systemic circulation. Data were analysed retrospectively on 438 melphalan perfusions performed for melanoma of the extremities during the period 1978-1990; continuous isotopic measurement of systemic leakage was carried out. The cumulative systemic leakage after 60 min perfusion was 0.9 per cent (95 per cent confidence interval 0.7-1.1 per cent). Systemic leakage of > or = 1 per cent was detected in 12.6 per cent of perfusions, > or = 5 per cent in 6.2 per cent and > or = 10 per cent in 1.4 per cent. In 2.3 per cent of patients, systemic side-effects in the form of mild transient bone marrow depression occurred. Six variables related to the perfusion technique were assessed by multivariate analysis for their influence on systemic leakage. The level of isolation and diameter of the venous cannula emerged as significant factors. In addition, ligation of the internal iliac vein provided optimal isolation during iliac perfusion.  相似文献   
95.
Different dental appliances have been recommended in the treatment of snoring. The aim of the present study was to compare three different dental appliances regarding patient tolerance and the effect of snoring. Fifteen consecutive snorers were randomly selected to treatment with either a mandibular advancement device (activator), a soft-palate lifter or a mouth-shield. The activator satisfactorily reduced snoring in four out of five patients. At four-year follow-up, two patients had discontinued the treatment, one due to craniomandibular disorder. The soft-palate lifter had insufficient effect on snoring in four out of five patients. The results suggest that the activator has a satisfactory tolerance and effect on snoring, while the soft-palate lifter and the mouth-shield are ineffective in the treatment of snoring.  相似文献   
96.
Exposure of porin from Escherichia coli to glutardialdehyde followed by SDS-gel electrophoresis in 3% polyacrylamide yielded three bands that were identified in order of decreasing mobility as monomers and two and three cross-linked polypeptide chains. The distribution of protein among the three species for different extents of reaction showed a remarkably good agreement with corresponding values predicted from cross linking theory for an oligomer composed of three identical subunits arranged according to a 3-fold rotation axis. Electrophoresis performed in 7.5% polyacrylamide yielded four bands that were assigned to polypeptide chain monomers, dimers, and two types of trimers carrying two and three intersubunit cross-links. Our findings provide evidence that the central premise of cross-linking theory, viz. that the intersubunit cross-links formed upon exposure of a protein to a bifunctional reagent be governed by the symmetry of the molecule, is valid. Careful interpretation of cross-linking experiments thus proves an effective method to assess the oligomeric structure of a protein and reveal the symmetry underlying the spatial arrangement of the subunits within the molecule.  相似文献   
97.
A new approach for forcing the state of a linear discrete-time system to zero in a minimum number of steps is discussed. The problem is formulated as the solution to a steady-state optimal control problem with no cost on the control. This problem in turn is set up as the solution to an associated eigenvalue problem. No special assumption on the open loop system matrix and/or the ratio of the number of states to controls is required. Stable numerical techniques are presented for solving for the feedback gain. Robust deadbeat tracking is also discussed.  相似文献   
98.
Contends that the ideal program of research to maximize clinical relevance combines 4 models of strategies. These are (1) convergent/convergent, (2) divergent/divergent, (3) divergent-theory/convergent-method, and (4) convergent-theory/divergent-method, and all are employed nomothetically at the level of theory and idiographically at the level of method. Model 1 serves to expand theoretical and procedural possibilities, giving clinicians the flexibility they need when working with individuals in service-delivery settings. Model 2 controls theoretical expansion. Model 3 controls procedural expansion. Model 4 may be used to provide preliminary demonstrations of feasibility that are then used to stimulate other forms of more directly relevant investigation. The products of this overall program of research will increasingly represent a useful body of tested theoretical and procedural possibilities and alternatives that clinicians can use for explaining and treating individual clients and for evaluating treatment outcomes in individually relevant terms. (32 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
99.
The Li-Strahler canopy reflectance model, driven by Landsat Thematic Mapper (TM) data, provided regional estimates of tree size and density in two bioclimatic zones in West Africa. This model exploits tree geometry in an inversion technique to predict average tree size and density from reflectance data using a few simple parameters measured in the field (spatial pattern, shape, and size distribution of trees) and in the imagery (spectral signatures of scene components). The model was tested in sparse woodland and wooded grassland in the Sahelian and Sudanian bioclimatic zones in West Africa  相似文献   
100.
Developed a 102-item sexual attitudes questionnaire that was completed by 439 female and 374 male undergraduates as part of a larger attitude study. Factor analyses yielded 8 factors on which 74 of the 102 items loaded. ANOVA of the individual items showed that female and male Ss differed on 73 of the 102 items. Females were more responsible, conventional, and idealistic, whereas males were more permissive, instrumental, and control- and power-oriented. The means suggested that females were moderately conservative in sexual attitudes, while males were moderately permissive. Based on the factor analysis, the present authors formed 5 preliminary sexual attitudes scales. Correlations among the summed scale scores indicated that the scales were largely independent of each other. It is suggested that the multidimensional complexity of sexual attitudes and empirical explanations for the continuing gender differences in sexual attitudes should be studied. (47 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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