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Although several studies have examined the relationship between intimate partner violence (IPV) and drug use among women in drug treatment programs, more information is needed to delineate differences, as a function of the specific drug used. Data from a random sample of 416 women attending methadone programs were analyzed to elucidate the differential associations between IPV and use of the following: marijuana only, cocaine only, heroin only, or cocaine and heroin. Prevalence of IPV among this sample far exceeded estimates from the general population. After adjusting for sociodemographic variables, use of cocaine only was significantly associated with an increased likelihood of experiencing IPV compared with no drug use. Similar results were found for women using both cocaine and heroin. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
83.
Despite oxycodone's (4,5-epoxy-14-hydroxy-3-methoxy-17-methylmorphinan-6-one) history of clinical use and the attention it has received as a drug of abuse, few reports have documented its pharmacology's relevance to its abuse or its mechanism of action. The purposes of the present study were to further characterize the analgesic effects of oxycodone, its mechanism of action, and its effects in terms of its relevance to its abuse liability. The results indicate that oxycodone had potent antinociceptive effects in the mouse paraphenylquinone writhing, hot-plate, and tail-flick assays, in which it appeared to be acting as a μ-opioid receptor agonist. It generalized to the heroin discriminative stimulus and served as a positive reinforcer in rats and completely suppressed withdrawal signs in morphinedependent rhesus monkeys. These results suggest that the analgesic and abuse liability effects of oxycodone are likely mediated through μ-opioid receptors and provide the first laboratory report of its discriminative stimulus, reinforcing, and morphine cross-dependency effects. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
84.
Levels of awareness for trauma and their consequences for research, treatment, and prevention within professional psychology and society are considered. When people must endure chronically traumatic environments, it may be adaptive to isolate from awareness information that would produce cognitive dissonance and threaten necessary relationships. Unawareness may also facilitate functioning in environments that invalidate the prevalence and impact of trauma. In addition, characteristics of the posttraumatic environment can promote or impede individuals' awareness of trauma and their psychological functioning. Though often initially adaptive, unawareness for trauma is linked to intergenerational transmission of trauma and its effects and may preclude public and professional attention to trauma treatment and prevention. Understanding the processes through which individuals become unaware or aware of traumatic experience is therefore essential to conducting effective psychotherapy with trauma survivors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The implementation of engineered surfaces presenting micrometer‐sized patterns of cell adhesive ligands against a biologically inert background has led to numerous discoveries in fundamental cell biology. While existing surface patterning strategies allow patterning of a single ligand, it is still challenging to fabricate surfaces displaying multiple patterned ligands. To address this issue we implemented laser scanning lithography (LSL), a laser‐based thermal desorption technique, to fabricate multifaceted, micropatterned surfaces that display independent arrays of subcellular‐sized patterns of multiple adhesive ligands with each ligand confined to its own array. We demonstrate that LSL is a highly versatile “maskless” surface patterning strategy that provides the ability to create patterns with features ranging from 460 nm to 100 μm, topography ranging from ‐1 to 17 nm, and to fabricate both stepwise and smooth ligand surface density gradients. As validation for their use in cell studies, surfaces presenting orthogonally interwoven arrays of 1 μm × 8 μm elliptical patterns of Gly‐Arg‐Gly‐Asp‐terminated alkanethiol self‐assembled monolayers and human plasma fibronectin are produced. Human umbilical vein endothelial cells cultured on these multifaceted surfaces form adhesion sites to both ligands simultaneously and utilize both ligands for lamella formation during migration. The ability to create multifaceted, patterned surfaces with tight control over pattern size, spacing, and topography provides a platform to simultaneously investigate the complex interactions of extracellular matrix geometry, biochemistry, and topography on cell adhesion and downstream cell behavior.  相似文献   
87.
Medical screws are a common mass-produced implantable medical component made of Titanium. To machine the threads of these types of components, thread whirling with carbide tools is typically used. However, tool wear and low cutting speed limit the productivity and increase the manufacturing cost of such medical parts. In this study, a direct motor driven thread whirling unit for an advanced Swiss-type CNC lathe was developed and it was used with advanced tool materials such as low binder content Cubic boron nitride (CBN) and Polycrystalline diamond (PCD) to find a cost-effective and more productive alternative to carbide tools.  相似文献   
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Electrical field flow fractionation (EFFF) has two perpendicular driving forces that help to produce an optimal separation of solute in a mixture [Giddings, Science 1993; 260:1456–1465]. For Couette flow based devices, the ratio of the velocity of the capillary walls offers an extra parameter that can be exploited to enhance the efficiency of EFFF applications. The analysis of the effects of this parameter on optimal times of separation is the subject matter of this contribution. The use of this additional parameter increases flexibility in the design of new devices for the improvement of the separation of solutes, such as proteins, DNA, and pharmaceuticals, as it will be illustrated with the results of this analysis (Jaroszeski et al., 2000 ; Trinh et al., 1999 ). The analysis has been illustrated by selecting parameter values that represent a number of potential useful applications. A set of five parameters (i.e., z, the valence; µ, electrophoretic mobility; Pe, Peclet number; Ω, the orthogonal applied electrical field; and R, the ratio of channel wall velocities) has been combined to obtain the best operating conditions for optimal separation of solutes. Results indicate that R, the ratio of the channel wall velocities, is actually the most important driving parameter.  相似文献   
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