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1.
The 2008 dioxin crisis occurred as a result of contamination of Irish pork. The event had significant implications for Ireland’s economy and the reputation of its agricultural industry, as well as raising concerns for human health. This study describes the results of a content analysis of Irish and UK newspaper coverage of the 2008 Irish dioxin crisis, as this is likely to provide insight into how public perceptions of this issue were shaped. Articles from 16 print publications were systematically sampled for the period December 2008 to February 2009. The resulting data set of 141 articles was examined using a coding protocol developed based on previous research and refined during piloting. Results indicated that the dioxin crisis was primarily portrayed by the media as an industry/economic crisis, dominant in 26.9% of articles in the sample. Within this dominant portrayal, the agricultural industry was frequently cited as being in crisis (42.6%); however, the implications of the crisis on the wider economic environment also received attention (17.7%). Differences between Irish and UK-based media were also examined, revealing that while the Irish media most frequently described the crisis in terms of its impact on the industry and economy, the UK media were more likely to portray the crisis as a risk to health. These dominant media messages and message framings have implications for the public understanding of the issue in each country and potential consequences regarding perception of the adequacy of existing food policy and regulatory oversight.  相似文献   
2.
Animal models have traditionally provided the basis for preliminary investigation of new techniques prior to trials taking place in human subjects. The timing of when to proceed with human trials is difficult, as the accuracy of preclinical models can only be determined with hindsight. This review outlines the progression from transplantation in animal models to man. Now that many transplant procedures are well established, it is possible to assess the predictive value and limitations of animal models. These results are of great importance in the current debate about composite tissue allotransplantation (CTA) and in particular facial transplantation. This progression of CTA from animal models to man is outlined and compared with early renal, cardiac, and liver transplants. There is some evidence to suggest that animal models may have been misleading in CTA and that this has effectively delayed the transition to humans. The role for animal models in facial transplantation, which is currently making the step to clinical trials, is discussed.  相似文献   
3.
Objective Changes in serum albumin may reflect systemic immunoinflammation and hypermetabolism in response to insults such as trauma and sepsis. Esophagectomy is associated with a major metabolic stress, and the aim of this study was to determine if the absolute albumin level on the first postoperative day was of value in predicting in-hospital complications. Methods A retrospective study of 200 patients undergoing esophagectomy for malignant disease at St. James Hospital between 1999 and 2005 was performed. Patients who had pre and postoperative (days 1, 3, and 7) serum albumin levels measured were included in the study. Patients were subdivided into three postoperative albumin categories <20 g/l, 20–25 g/l, >25 g/l. Logistic regression analysis was performed to calculate the odds of morbidity and mortality according to the day 1 albumin level. Results Patients with an albumin of less than 20 g/l on the first postoperative day were twice as likely to develop postoperative complications than those with an albumin of greater than 20 g/l (54 vs 28% respectively, p < 0.011). Correspondingly, these patients also had a significantly higher rate of Adult Respiratory Distress Syndrome (22 vs 5%, p < 0.001), respiratory failure (27 vs 8%, p < 0.01) and in-hospital mortality (27 vs 6% (p < 0.001). On multivariate logistic regression analysis, day 1 albumin level was independently related to postoperative complications (odds ratios, 0.89: 95%; confidence intervals, 0.83–0.96; p < 0.005). In addition, albumin <20 g/l on the first postoperative day was associated with the need for further surgery and a return to ICU. Conclusion Serum albumin concentration on the first postoperative day is a better predictor of surgical outcome than many other preoperative risk factors. It is a low cost test that may be used as a prognostic tool to detect the risk of adverse surgical outcomes.  相似文献   
4.
The rejection of sponge matrix allografts across H-2 barriers has generally been found to contain specifically sensitized cytotoxic T cells to donor alloantigen. There is one exception: sponge matrix allografts that differ only with respect to class II alloantigens do not contain specifically sensitized cytotoxic T cells. We therefore investigated the capacity of infiltrating cells removed from sponge matrix allografts to generate delayed hypersensitivity reactions after exposure to fresh alloantigen in a footpad assay. Cells infiltrating class I and II allografts were equally capable of eliciting delayed footpad reactions when injected with specific donor alloantigen into the footpads of naive responder strain mice. Allosensitized T-lymphocyte clones of helper or cytotoxic type were also capable of initiating delayed-type hypersensitivity (DTH) reactions in vivo. We conclude that rejecting allografts across class I or II alloantigenic barriers are infiltrated by cells capable of effecting DTH reactions, in addition to their capacity to exert specific helper or specific cytotoxic reactions. The results also support that both helper and cytotoxic T cells can participate in allospecific DTH reactions.  相似文献   
5.
Aim: This article reviews research centred around juvenile bipolar disorder with particular reference to diagnostic difficulties. Putative deficits are scrutinized with respect to trait likelihood and the roles of neuropsychology and neuroimaging in enhancing our understanding of juvenile bipolar disorder are discussed. Methods: Search terms including childhood, adolescent, youth and juvenile combined with the terms ‘bipolar disorder’, mania, depression and hypomania were used to identify relevant studies in MEDLINE and PsychLit. Results: Over recent years research into this relatively new disorder has increased phenomenally. Key issues within the field include diagnostic specificity, the heritability of the disorder, the impact of comorbidity and the implications of neuropsychological and neuroimaging findings. Conclusion: Despite concerning controversies in literature the diagnosis of bipolar disorder in children and adolescents as compared with adults, promising future research directions include better neurological characterization of the disorder through the application of findings from clinical populations, neuropsychological and neuroimaging research.  相似文献   
6.
INTRODUCTION: Concern about the potential detrimental side-effects of beta-blockade on pulmonary function often dissuades against their perioperative use in patients undergoing major arterial surgery (especially in those with chronic obstructive pulmonary disease (COPD)). In this study we aimed to establish prospectively the clinical relevance of these concerns. METHODS: After ethics committee approval and individual informed consent, the pulmonary function of twenty patients (mean age 68.7 years (range 43-82), 11 males) scheduled to undergo non-emergency major vascular surgery was studied by recording symptoms and spirometry before and after institution of effective beta-blockade. Fifteen patients (75%) had significant smoking histories (mean pack years/patient=50), while 12 (60%) had COPD. RESULTS: All patients tolerated effective beta-blockade satisfactorily without developing either subjective deterioration in symptoms or significant change on spirometry. The mean change in FEV1 following adequate beta-blockade was 0.05+/-0.24 liters (95% CI -0.06 to +1.61), p=0.35, giving a mean percentage change of 3.18%+/-11.66 (95% CI -2.26 to 8.62). CONCLUSIONS: Previously held concerns about worsening pulmonary function through the short-term use of beta-blockers should not dissuade their perioperative usage in patients with peripheral vascular disease. Furthermore, the accuracy of pulmonary function tests in preoperative assessment and risk stratification also appears unaffected by this therapy.  相似文献   
7.
What should nurse teachers be doing? A preliminary study   总被引:1,自引:0,他引:1  
There is little doubt that the role of the nurse teacher is complex and multifaceted in nature. The apparently conflicting demands of NHS trusts and education in the United Kingdom, at the time of integration of nurse education into the higher education sector, further complicates the role. This recognition underlines the need to capture and measure key aspects of nurse teacher function in order to maximize educational gain. Using a comprehensive literature review, focus group discussions and a small number of individual semi-structured interviews, this preliminary study explored the issue of teacher workload, from the perspective of the principal stakeholders in nurse and higher education. Competing research and clinical practice objectives for nurse teachers are identified against a background of changing health care provision, reduced availability of placements and an increased need for evidence-based practice.  相似文献   
8.
Although magnetic resonance imaging (MRI) is a valuable aid in the initial diagnosis of multiple sclerosis (MS), quantitatively MRI has been disappointing in staging and evaluating therapy protocols by means of serial examinations. In this study, image processing algorithms were developed for the global analysis of MR images of the cerebrum. Limited three-dimensional segmentation was achieved through histogram analysis by these algorithms, which are essentially operator independent. The effects of coil response and tip angles, patient positioning, and interslice gap thicknesses were examined for 10 MS patients with repeated examinations for a total of 72 images. Effects of technique and instrumentation errors were approximately 6%, and agreement between two independent operators for measuring the total MR pixel sum from periventricular effusions and intense MS plaques was better than 97% with a standard deviation of 2.9%.  相似文献   
9.
Successful surgical palliation for carcinoma of the cardia and lower oesophagus is often compromised by anastomotic failure or local recurrence. These complications follow technical difficulty in achieving adequate resection and a safe anastomosis through inappropriate surgical exposure, often via the left chest. A technique of oesophagogastrectomy is described employing a simultaneous right abdominothoracic approach without division of either costal margin or diaphragm. Synchronous laparotomy and thoractomy facilitates both resection and anastomosis, and obviates the necessity to turn the patient over and redrape halfway through the operation. Closure of the distal stomach and the gastro-oesophageal anastomosis are performed using staplers. No anastomotic leaks were detected in the 15 patients described.  相似文献   
10.
Adequate fixation with several commonly used anterior cervical plate systems requires that the screws penetrate both the anterior and posterior cortices of the vertebral bodies. This report emphasizes the shortcomings of plain film and fluoroscopic examinations in confirming screw position through the posterior vertebral cortex in three patients with lower cervical trauma or tumor. These cases and radiographs of isolated vertebrae from the cervicothoracic region demonstrate the inadequacy of plain film/fluoroscopy for determination of the position of anterior cervical plate screws in relation to the posterior cortex. Only axial images such as those obtained with computed tomography are able to show the exact relationship of the screws to the posterior cortical curvature in C7 and T1.  相似文献   
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