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81.
Two studies involving 135 university students examined the relation between attitudes and the recall of past behaviors. Both experiments utilized the same paradigm: First, Ss' attitudes on an issue were manipulated; then Ss were asked to recall past behaviors relevant to the newly formed attitude. The results indicate that attitudes can exert a directive influence on recall of personal histories. It is suggested that much like a self-fulfilling prophecy, the process of behavioral review may increase the control that attitude exerts over future behavior, producing an increase in attitude–behavior consistency. (30 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
82.
Cytostatic activity of 1,10-phenanthroline derivatives generated by the clip-phen strategy 总被引:1,自引:0,他引:1
Pitié M Croisy A Carrez D Boldron C Meunier B 《Chembiochem : a European journal of chemical biology》2005,6(4):686-691
The cytostatic activities of a series of twelve 1,10-phenanthroline (Phen) derivatives and of their copper complexes were studied on L1210 murine leukemia cells. Large increases in the biological activity were observed for compounds of the 3-Clip-Phen series, in which two Phen moieties were bridged at their C3 positions by an alkoxy linker, the 3-pentyl-Clip-Phen derivative showing an IC(50) value of 130 nM while Phen shows an IC(50) value of 2500 nM under the same conditions. IC(50) values seemed to be modulated not only by the position, the nature, and the length of the linker of Clip-Phen but also by hydrophobicity. Since copper complexes of Phen are chemical nucleases and nucleic acids are thus a potential target for these compounds, the corresponding copper complexes were also studied. Copper complexation of the 3-Clip-Phen ligands did not increase their biological activities. Attempts to vectorize 3-Clip-Phen derivatives with a DNA binder such as spermine or with a cell-penetration peptide failed to increase their biological activity relative to the original 3-Clip-Phen series. 相似文献
83.
Poly(vinyl chloroformates) of high molecular weight have been successfully modified by amines and by KCN. Poly (vinyl carbonates) have been prepared by polymerization of phenyl vinyl carbonate. 相似文献
84.
F Offner C Cordonnier P Ljungman HG Prentice D Engelhard D De Bacquer F Meunier B De Pauw 《Canadian Metallurgical Quarterly》1998,26(5):1098-1103
A retrospective analysis of 48 patients with documented or probable invasive aspergillosis (IA) prior to bone marrow transplantation (BMT) was conducted in 16 centers. Treatment of primary IA was medical in all 48 patients and surgical in 20; clinicoradiological resolution of IA occurred in 30 of 48 patients. Pretransplantation risk factors for relapse IA, total mortality, and IA-related mortality were analyzed by multivariate logistic regression with the following dichotomous risk factors: surgery as part of the initial treatment, resolution of IA by the time of BMT, donor type, conditioning regiment, total-body irradiation, T cell depletion, immunosuppressive therapy, type of antifungal prophylaxis, and growth factor prophylaxis. Conditioning with busulfan/cyclophosphamide was associated with a beneficial outcome for total survival and reduced IA-related mortality. Posttransplantation risk factors such as the development of graft-vs.-host disease (GVHD), therapy for GVHD, and the duration of neutropenia did not have a significant effect on relapse IA, IA-related mortality, or total mortality. The overall incidence of relapse IA was lower than expected (33% [16 of 48 patients]), but the mortality rate among relapsed patients was 88% (14 of 16). Patients receiving prophylaxis with absorbable or intravenous antifungals had less relapses of IA than did those not receiving prophylaxis (12 of 41 vs. four of seven, respectively). This finding reflects the need for better prophylaxis and new antifungal treatments for patients undergoing BMT who have a history of IA. 相似文献
85.
Thin films of c-WN: H are synthesized by plasma enhanced chemical vapor deposition using a hot wall type reactor. These films are polycrystalline. The formation temperatures are in the 350-620°C range with WF6, NH3, as precursors and Ar and H2 as feed gas. XRD and XPS analysis show a chemical composition close to that of WN but a structure varying from tungsten form to tungsten nitride. ERDA and RBS analysis provide a hydrogen content and its; concentration profile through the thickness of the coating. AFM measurements are performed to evaluate the growth conditions. 相似文献
86.
The operation of hydrogenated amorphous silicon devices depends crucially on the interplay between the dynamics of free and trapped carriers. This is due to a density of acceptor and donor states present in the mobility gap of amorphous materials. It is shown that Gummel's method used for the simulation of crystalline-material-based devices has to be modified to account for this interplay. The midgap density of states is identified as the parameter controlling the nature of the dynamics of the carriers and this is illustrated with two examples: the 1D Schottky diode and the 2D static induction transistor 相似文献
87.
Alerts APA researchers and readers that the article "Does violence beget violence? A critical examination of the literature" by C. S. Widom (Psychological Bulletin, 1989, Vol 106(1), Jul, 3–28) has been amplified and reprinted in a book chapter: Widom, C. S. (1989). The intergenerational transmission of violence. In N. A. Weinger & M. E. Wolfgang (Eds.), Pathways to criminal violence. Newbury Park, CA: Sage. Through an oversight, cross-reference between the two publications and information in the copyright for this article were omitted from the Sage book. The copyright is held by the American Psychological Association. (The following abstract of this article originally appeared in PA, Vol 76:36811.) Critically examines the "violence breeds violence" hypothesis broadly defined. Organized into 7 sections, the literature review includes (a) the abuse breeds abuse hypothesis; (b) reports of small numbers of violent/homicidal offenders; (c) studies examining the relationship of abuse and neglect to delinquency; (d) to violent behavior, and (e) to aggressive behavior in infants and young children; (f) abuse, withdrawal, and self-destructive behavior; and (g) studies of the impact of witnessing or observing violent behavior… (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
88.
Speckle motion artifact under tissue rotation 总被引:1,自引:0,他引:1
Kallel F. Bertrand M. Meunier J. 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》1994,41(1):105-122
Speckle patterns in ultrasound images may move in a way which bears no simple relationship to the motion of the corresponding tissues. In some instances the speckle motion replicates the underlying tissue motion, in others it does not. The authors name “speckle motion artifact” the difference between the speckle and the underlying tissue motion. An echographic image formation model is used to study the motion artifact produced by a rotating phantom and observed by a linear scan imaging system with a Gaussian beam. The authors propose that when the tissue is modeled as a random array of small and numerous scatterers, such motion aberration be accounted for by the 2D phase characteristics of the imaging system. An analytic prediction of this motion artifact in relation to the imaging system characteristics (beam width, transducer frequency, pulse duration) is presented. It is shown that the artifact results from the curvature of the system point spread function, which in turn determines the curvature of the 2D phase characteristics. To the authors' knowledge, it is the first time a comprehensive model of ultrasonic speckle motion artifact is presented. The model has been developed to study rotation-induced artifact; the method is however quite general and can be extended to study the effects of other tissue motion, in particular deformation and shear 相似文献
89.
Erickson MC Liao J Payton AS Riley DG Webb CC Davey LE Kimbrel S Ma L Zhang G Flitcroft I Doyle MP Beuchat LR 《Journal of food protection》2010,73(10):1809-1816
Environmental pests may serve as reservoirs and vectors of zoonotic pathogens to leafy greens; however, it is unknown whether insect pests feeding on plant tissues could redistribute these pathogens present on the surface of leaves to internal sites. This study sought to differentiate the degree of tissue internalization of Escherichia coli O157:H7 when applied at different populations on the surface of lettuce and spinach leaves, and to ascertain whether lettuce-infesting insects or physical injury could influence the fate of either surface or internalized populations of this enteric pathogen. No internalization of E. coli O157:H7 occurred when lettuce leaves were inoculated with 4.4 log CFU per leaf, but it did occur when inoculated with 6.4 log CFU per leaf. Internalization was statistically greater when spinach leaves were inoculated on the abaxial (underside) than when inoculated on the adaxial (topside) side, and when the enteric pathogen was spread after surface inoculation. Brief exposure (~18 h) of lettuce leaves to insects (5 cabbage loopers, 10 thrips, or 10 aphids) prior to inoculation with E. coli O157:H7 resulted in significantly reduced internalized populations of the pathogen within these leaves after approximately 2 weeks, as compared with leaves not exposed to insects. Surface-contaminated leaves physically injured through file abrasions also had significantly reduced populations of both total and internalized E. coli O157:H7 as compared with nonabraded leaves 2 weeks after pathogen exposure. 相似文献
90.
Properties of polymeric microgels are influenced by the internal polymer cross-linked structure, but tools to quantitatively analyze this internal structure are limited. With the finding that polymer networks alter the diffusivity and subsequent excimer formation of pyrene, this study used the ratio between pyrene excimer and monomer emission to determine the number of cross-links (N) and average pore size (ξ) in poly(ethylene glycol) diacrylate (PEGDA) microgels. A calibration curve to relate pyrene emission to N and ξ in PEGDA hydrogels was prepared and used to calculate N and ξ in PEGDA microgels. The pyrene emission indicated that PEGDA microgels had a higher cross-linking density and a smaller average pore size when compared with bulk cross-linked hydrogels of the same PEGDA concentration. The analytical method demonstrated in this study may be useful for fine-tuning polymeric microgel properties for a broad array of applications. 相似文献