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This study examined the neuroprotective effects and possible hepatotoxicity of (-)-epigallocatechin gallate (EGCG) in a rat model of transient focal cerebral ischemia. Male Sprague-Dawley rats (265-295 g) were treated with either 50 mg kg(-1) of EGCG or saline, i.p., immediately post-ischemia and every day thereafter, in a middle cerebral artery occlusion model of stroke. Sacrifice occurred 72 h post-ischemia and 2,3,5-triphenyltetrazolium chloride staining was used to quantify neuronal infarction. Hepatotoxicity was determined by taking blood samples for plasma alanine aminotransferase (ALT) activity. Spleen, kidney, liver and testes wet weights were also recorded. Total infarct volume was significantly (P<0.05) reduced in the EGCG-treated group as compared to controls. Analysis of the mean infarct area showed a significant (P<0.05) decrease in slices 6 and 7 in the EGCG-treated group. No significant differences were found in organ weights or ALT levels between treatment groups. Our findings, in part, validate and extend previous observations illustrating that 50 mg kg(-1), i.p. EGCG is non-toxic and neuroprotective. However, we also found that EGCG treatment appreciably increased (>50%) the number of animals that developed an intracerebral hemorrhage. We therefore conclude that 50 mg kg(-1) EGCG is not a viable intervention for the acute treatment of cerebral ischemia, as it is likely to increase the risk of intracerebral hemorrhaging.  相似文献   
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Previous investigations indicate that polymyxin B inhibits attachment of lipopolysaccharides (O antigens) to erythrocytes and subsequent hemagglutination by the corresponding bacterial antibodies. In this study the effect of this antibiotic was compared to that of the aminoglycosides gentamicin, tobramycin, and amikacin. Using both crude O antigens and highly purified Lipopolysaccharides, polymyxin B was at least 100 times more effective than the aminoglycosides. Amikacin proved to be less effective than gentamicin and tobramycin.  相似文献   
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The present study investigated the efficacy of a specific self-control procedure, self-imposed timeout, in reducing the excessive alcohol consumption of two subjects (husband and wife). Each of three target behaviors, amount of alcohol per drink, number of drinks per day, and rate of consumption were treated sequentially in a multiple baseline design. Results demonstrate that treatment of the target behaviors successfully reduced total alcohol consumption to acceptable levels over the seven week program and that these reductions were maintained as long as one year after the timeout contingency had been withdrawn.  相似文献   
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Health disparities have dominated recent discourse among public health and medical researchers. Ever since the United States began to compile health statistics, differences in health status have been noted between majority and non-majority populations. Myriad approaches have been undertaken in an attempt to reduce or eliminate racial and ethnic disparities in health. However, the disparities continue to persist. We are at a point in our history where innovative strategies must be explored that will be more effective in addressing racial and ethnic disparities in health. In large part, health disparities exist as a result of inequitable distribution of goods, resources, services and power in America. We have learned that improvements in health cannot come about solely through primary and secondary interventions but rather through an examination of the availability of resources that would allow individuals to improve their health. The goal of this paper is to provide an overview of the contextual factors that affect health disparities, to integrate theory to address disparities and to provide recommendations to encourage systematic changes to eliminate health disparities. It is hoped that this paper will bring about a national discussion relating to addressing the real issues we face in reducing and ultimately eliminating health disparities.  相似文献   
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The purpose of this study was to identify how healthcare clients achieve and maintain a sense of control over their health. The literature review conducted refers to: (i) key definitions of control, (ii) locus of control, and (iii) control and wellbeing. Participants with a range of acute and chronic health conditions and who had been hospitalised at some point were selected for the study. Symbolic interactionism (Blumer, 1969) and modified grounded theory of Strauss & Corbin (1998) provided the frameworks for this study. During the six month study period, data were collected from sixty participants and included interviews, participant observation, reviewing participants' records (nursing care plans, nursing notes and case histories), the nursing units' philosophy, organisational charts, policies and procedures, annual reports, consumer brochures and any other relevant information sources. Findings from the study indicated that participants moved from feeling vulnerable to having a sense of control through to being purposefully active. Vulnerability was associated with: (i) having limited choices in respect to their health, (ii) lacking adequate health information to make choices, (iii) being ignored by health providers with respect to their needs, and (iv) lacking friend/family supports. Purposefully activating was associated with three major categories: (i) reflecting, (ii) being self-determiningly involved and (iii) normalising. Findings from this study could be used by health care clients who want a sense of control over their health care, and also by health care providers who wish to support clients in the healthcare process.  相似文献   
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Schmithorst VJ  Brown RD 《NeuroImage》2004,22(3):1414-1420
The suitability of a previously hypothesized triple-code model of numerical processing, involving analog magnitude, auditory verbal, and visual Arabic codes of representation, was investigated for the complex mathematical task of the mental addition and subtraction of fractions. Functional magnetic resonance imaging (fMRI) data from 15 normal adult subjects were processed using exploratory group Independent Component Analysis (ICA). Separate task-related components were found with activation in bilateral inferior parietal, left perisylvian, and ventral occipitotemporal areas. These results support the hypothesized triple-code model corresponding to the activated regions found in the individual components and indicate that the triple-code model may be a suitable framework for analyzing the neuropsychological bases of the performance of complex mathematical tasks.  相似文献   
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