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排序方式: 共有691条查询结果,搜索用时 15 毫秒
61.
Used concentrated cigarette smoke as an aversive agent in the treatment of 89 habitual cigarette smokers. A factorial design assessed the incremental efficacy of 3 procedures, hypothesized to increase treatment durability, as a function of client characteristics. The 1st, treatment focus, contrasted procedures considered optimal for internal vs external locus of control clients (measured with Rotter's Internal-External Control Scale). The 2nd, punishment, assessed an instruction to punish postclinic smoking with stimulus satiation conditions. The 3rd, timing of attitude change, presented an attitude change manipulation either before or after behavior change. The Eysenck Personality Inventory and C. S. Keutzer's effective cognitive dissonance measure were also administered. Changes in smoking behavior were monitored over a 6-mo period. 2 of the 3 treatment factors, treatment focus and timing of attitude change, interacted significantly with client characteristics in determining treatment outcome. Findings support the principle of tailoring therapeutic procedures to individual differences. (25 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
62.
Stuart J. McLelland Philip J. Ashworth James L. Best John R. Livesey 《Canadian Metallurgical Quarterly》1999,125(5):463-473
Longitudinal stripes are a common bed form in heterogeneous alluvial sediments and consist of periodic, spanwise variations in bed texture and elevation that are aligned parallel to the mean flow direction. This paper quantifies mean and turbulent flow structures over self-formed sediment stripes in a weakly bimodal sand and gravel mixture. Turbulence anisotropy generates two secondary circulation cells across the channel half-width, which produce a cross-stream perturbation in boundary shear stress. The interaction between this flow structure and the selective transport of bed material generates spanwise sediment sorting that is symmetrical about the centerline. Finer sediments are entrained from regions of high shear stress, transported laterally by the secondary flow, and deposited in regions of lower shear stress. Lateral changes in bed texture further enhance the near-bed secondary flow, which provides a positive feedback mechanism for stripe growth. In bimodal sediments, at shear stresses just above the entrainment threshold, stripes may replace lower-stage plane beds. At higher shear stresses the coarser sediment becomes more mobile and the stripes are replaced by flow transverse bed forms. 相似文献
63.
Deldin Patricia J.; Deveney Christen M.; Kim Andrea S.; Casas Brooks R.; Best Jennifer L. 《Canadian Metallurgical Quarterly》2001,110(2):267
Mood-congruent working memory biases were examined in a delayed matching to sample paradigm using the slow wave (SW) event-related brain potential (ERP) component. Mood-congruent working memory biases, indexed by SW amplitudes, were demonstrated among individuals experiencing a major depressive episode (MDE) and nondepressed controls but not individuals with dysthymia. However, analyses of symptom severity demonstrated that those with dysthymia exhibited significantly less negative SW amplitudes with increasing depressive mood severity, whereas individuals with major depression demonstrated more negative SW amplitudes with increasing depressive mood severity. These results are discussed in the context of diagnostic specificity for cognitive biases associated with working memory of mood-disordered individuals. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
64.
65.
SCALING IN SITU BIOREMEDIATION PROBLEMS BY APPLICATION OF MULTIPHASE, MULTICOMPONENT TRANSPORT THEORY 总被引:1,自引:0,他引:1
Robert J. Mackinnon Keith A. Schimmel Cynthia A. Loehr James F. Best James H. Wolfram 《Chemical Engineering Communications》1997,158(1):123-156
A methodology for scaling in situ bioremediation problems is presented. This methodology is based on multiphase, muiticomponent transport theory and employs inspectional analysis and numerical sensitivity studies. A general mathematical model that describes subsurface aerobic biotransformation of organic chemical species in a multiphase setting is first presented. This general model is applied to the specific case of microbial enhanced vapor-vacuum extraction (MEVVE) in a one-dimensional zone of immobile liquids. The resulting simplified MEVVE model considers rate-dependent interphase mass transfer, a flowing gaseous phase, a single hydrocarbon pseudo-component, and either oxygen or hydrocarbon limited microbial activity. By inspectional analysis a set of dimensionless groups are derived that represent the various model parameters. A scries of numerical sensitivity studies are presented that examine the impact of selected dimensionless groups on overall system biotransformation rates. This analysis demonstrates that overall biotranformation rates can be significantly limited not only by insufficient transport of oxygen in the gaseous phase, but also by interfacial mass transfer resistance between nonaqueous phase liquid globules and adjacent fluids. Finally, an examination of the selected dimensionless groups reveals the parameter requirements for properly scaled MEVVE tests. These results indicate the need for further investigation of the importantance of fluid distributions in the pore space and their impact on the design of laboratory and field tests. 相似文献
66.
Eng San Thian Xiang LiJie Huang Mohan J. EdirisingheWilliam Bonfield Serena M. Best 《Thin solid films》2011,519(7):2328-2331
The biological performance of orthopaedic and oral metallic implants can be enhanced significantly by the application of bioactive coatings. In this work, a cost-efficient alternative to the traditional technique to produce a hydroxyapatite (HA) coating with a nanostructured feature onto a metallic implant surface at room temperature via electrospray deposition, is presented. To evaluate the bioactive capacity of these nanoHA (nHA) coatings in vitro, an acellular simulated body fluid soaking experiment and a human osteoblast (HOB) cell culture work were conducted. Under these physiological conditions, the accelerated apatite precipitation process occurred on the nHA-coated titanium surfaces as compared to the uncoated titanium surfaces. HOB cells developed mature cytoskeletons with distinct evidence of actin stress fibres and vinculin adhesion plaques, on these nHA coatings. Hence, this deposition technique holds great potential in producing high quality nHA coatings for biomedical applications. 相似文献
67.
Summary A non-reducing disaccharide has been isolated from the kernels of tung (Aleurites fordi Hemsl.) and identified as sucrose. 相似文献
68.
Yourong Feng Qi Chen Sien Yee Lau Bridget W. Tsai Katie Groom Carolyn J. Barrett Lawrence W. Chamley 《International journal of molecular sciences》2022,23(21)
Placental extracellular vesicles (EVs) have increasingly been recognized as a major mediator of feto-maternal communication. However, the cellular and molecular mechanisms of the uptake of placental EVs by recipient cells are still not well-understood. We previously reported that placental EVs target a limited number of organs in vivo. In the current study, we investigated the mechanisms underlying the uptake of placental EVs into target cells. Placental EVs were derived from explant cultures of normal or preeclamptic placentae. The mechanisms underlying the uptake of placental EVs were elucidated, using the phagocytosis or endocytosis inhibitor, trypsin-treatment or integrin-blocking peptides. The endothelial cell activation was studied using the monocyte adhesion assay after the preeclamptic EVs exposure, with and/or without treatment with the integrin blocking peptide, YIGSR. The cellular mechanism of the uptake of the placental EVs was time, concentration and energy-dependent and both the phagocytosis and endocytosis were involved in this process. Additionally, proteins on the surface of the placental EVs, including integrins, were involved in the EV uptake process. Furthermore, inhibiting the uptake of preeclamptic EVs with YIGSR, reduced the endothelial cell activation. The interaction between the placental EVs and the recipient cells is mediated by integrins, and the cellular uptake is mediated by a combination of both phagocytosis and endocytosis. 相似文献
69.
Shaun C. Lee Karina K. C. Leung Audrey C. Y. Chung Elysia S. Y. Wong Katie L. Meehan Jason Y. K. Chan 《International journal of molecular sciences》2022,23(22)
Biomarkers are crucial in oncology, from detection and monitoring to guiding management and predicting treatment outcomes. Histological assessment of tissue biopsies is currently the gold standard for oropharyngeal cancers, but is technically demanding, invasive, and expensive. This systematic review aims to review current markers that are detectable in biofluids, which offer promising non-invasive alternatives in oropharyngeal carcinomas (OPCs). A total of 174 clinical trials from the PubMed search engine in the last 5 years were identified and screened by 4 independent reviewers. From these, 38 eligible clinical trials were found and subsequently reviewed. The biomarkers involved, categorized by human papillomavirus (HPV)-status, were further divided according to molecular and cellular levels. Recent trials investigating biomarkers for both HPV-positive and HPV-negative OPCs have approaches from various levels and different biofluids including plasma, oropharyngeal swabs, and oral rinse. Promising candidates have been found to aid in detection, staging, and predicting prognosis, in addition to well-established factors including HPV-status, drinking and smoking status. These studies also emphasize the possibility of enhancing prediction results and increasing statistical significance by multivariate analyses. Liquid biopsies offer promising assistance in enhancing personalized medicine for cancer treatment, from lowering barriers towards early screening, to facilitating de-escalation of treatment. However, further research is needed, and the combination of liquid biopsies with pre-existing methods, including in vivo imaging and invasive techniques such as neck dissections, could also be explored in future trials. 相似文献
70.