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231.
STUDY OBJECTIVE: There is little guidance on how to identify useful evidence about the health effects of social interventions. The aim of this study was to assess the value of different ways of finding this type of information. DESIGN: Retrospective analysis of the sources of studies for one systematic review. SETTING: Case study of a systematic review of the effectiveness of interventions in promoting a population shift from using cars towards walking and cycling. MAIN RESULTS: Only four of the 69 relevant studies were found in a "first-line" health database such as Medline. About half of all relevant studies were found through the specialist Transport database. Nine relevant studies were found through purposive internet searches and seven relevant studies were found by chance. The unique contribution of experts was not to identify additional studies, but to provide more information about those already found in the literature. CONCLUSIONS: Most of the evidence needed for this review was not found in studies indexed in familiar literature databases. Applying a sensitive search strategy across multiple databases and interfaces is very labour intensive. Retrospective analysis suggests that a more efficient method might have been to search a few key resources, then to ask authors and experts directly for the most robust reports of studies identified. However, internet publications and serendipitous discoveries did make a significant contribution to the total set of relevant evidence. Undertaking a comprehensive search may provide unique evidence and insights that would not be obtained using a more focused search.  相似文献   
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OBJECTIVE: Eating disorders have high comorbidity with mood, anxiety, and substance use disorders. Using twins from the population-based Minnesota Twin Family Study (MTFS), we examined comorbidity and shared transmission between eating pathology and these disorders. METHOD: Female twins (N = 672), ages 16-18 years, completed structured clinical interviews assessing anorexia nervosa and bulimia nervosa (as described in the 4th ed. of the Diagnostic and Statistical Manual of Mental Disorders [DSM-IV; American Psychiatric Association, 1994]), as well as mood, anxiety, and substance use disorders (as described in the 3rd Rev. ed. of the Diagnostic and Statistical Manual of Mental Disorders [DSM-III-R]). Shared transmission was examined using a discordant monozygotic (MZ) twin design. RESULTS: Significant comorbidity was found between eating disorders and major depression, anxiety disorders, and nicotine dependence. Within MZ twin pairs discordant for eating disorders (n = 14), non-eating-disordered cotwins demonstrated increased risk for anxiety disorders compared with controls. Similarly, within MZ twin pairs discordant for anxiety disorders (n = 52), non-anxiety-disordered cotwins demonstrated increased risk for eating disorders compared with controls. DISCUSSION: Findings support shared transmission between eating disorders and anxiety disorders. However, the nature of this shared diathesis remains unknown.  相似文献   
233.
Employers will continue to have a key role in the U.S. health system. Unfortunately, their purchasing practices have fallen far short of ideal. Large employers can lead the way for smaller companies, but by not routinely using competitive bidding or integrating quality into their specifications, they have sent mixed messages to both health plans and providers. Employers need to either get serious about buying health care as individual companies or explore other options. To purchase effectively, both health care expertise and the sustained commitment of senior leadership are needed. Whether employers can reverse their historical performance and become better purchasers is an open question.  相似文献   
234.
Technical success rates for percutaneous restoration of thrombosed arteriovenous grafts are high. However, in thrombosed grafts without restorable original outflow veins, percutaneous salvage is usually not possible. In this situation, patients are referred for bypass grafting or recreation of their vascular access sites. This report describes a patient in whom the original outflow vein at the venous anastomosis was completely obliterated and in whom vascular access was successfully salvaged by percutaneously reanastomosing the venous stump of the thrombosed graft with an adjacent patent vein. This procedure is technically feasible for the salvage of a thrombosed graft.  相似文献   
235.
The decision whether, if ever, to intervene in the affairs of a sovereign state with military force has become a critical issue of the post Cold War era. In 2000 the Canadian government launched the International Commission on Intervention and State Sovereignty (ICISS), which in 2001 published its findings in The Responsibility to Protect. The Commission found broad support for the notion of sovereignty not only as a right, but also a responsibility, the responsibility of a state to provide protection for its people. The primary responsibility for protecting citizens rests with states. But when states are unable or unwilling to provide this protection, or are themselves the perpetrators of atrocities, the Commission argues that the international community has a responsibility temporarily to step in, forcefully if necessary. The Commission resisted the temptation to identify human rights violations falling short of outright killing or ethnic cleansing. This eliminates the possibility of intervening on the basis of systematic oppression of human rights or intervening to remove a military dictatorship. The intention of the report was to provoke debate; to strengthen the role of the United Nations and ensure that such interventions were multilateral and meeting the wider needs of a region and not the interests of major powers. There is an ongoing need to ensure that the Security Council is effective and that resources match the political will. These debates must continue within a UN framework.  相似文献   
236.
Relationship Between Tissue Ingrowth and Mesh Contraction   总被引:3,自引:0,他引:3  
Contraction is a well-documented phenomenon occurring within two months of mesh implantation. Its etiology is unknown, but it is suggested to occur as a result of inadequate tissue ingrowth into the mesh and has been associated with hernia recurrence. In continuation of our previous studies, we compared tissue ingrowth characteristics of large patches of polyester (PE) and heavyweight polypropylene (PP) and their effect on mesh contraction. The materials used were eight PE and eight PP meshes measuring 10 × 10 cm2. After random assignment to the implantation sites, the meshes were fixed to the abdominal wall fascia of swine using interrupted polypropylene sutures. A necropsy was performed three months after surgery for evaluation of mesh contraction/shrinkage. Using a tensiometer, tissue ingrowth was assessed by measuring the force necessary to detach the mesh from the fascia. Histologic analysis included inflammatory and fibroblastic reactions, scored on a 0–4 point scale. One swine developed a severe wound infection that involved two PP meshes and was therefore excluded from the study. The mean area covered by the PE meshes (87 ± 7 cm2) was significantly larger than the area covered by the PP meshes (67 ± 14 cm2) (p = 0.006). Tissue ingrowth force of the PE meshes (194 ± 37 N) had a trend toward being higher than that of the PP meshes (159 ± 43 N), although it did not reach statistical significance. There was no difference in histologic inflammatory and fibroblastic reactions between mesh types. There was a significant correlation between tissue ingrowth force and mesh size (p = 0.03, 95% CI: 0.05–0.84). Our results confirm those from previous studies in that mesh materials undergo significant contraction after suture fixation to the fascia. PE resulted in less contraction than polypropylene. A strong integration of the mesh into the tissue helps prevent this phenomenon, which is evidenced by a significant correlation between tissue ingrowth force and mesh size. Presented at the Southeastern Surgical Congress 2004 Meeting, Atlanta, GA, January 31–February 3, 2004 This study was sponsored by Promethian Surgical Devices, Boston, MA, USA.  相似文献   
237.
We report findings from a Web-based survey of the International Society for Traumatic Stress Studies' members (n = 227) regarding use of trauma exposure and posttraumatic assessment instruments. Across clinical and research settings, the most widely used tests included the Posttraumatic Stress Diagnostic Scale, Trauma Symptom Inventory, Life Events Checklist, Clinician-Administered Post-traumatic Stress Disorder (PTSD) Scale, PTSD Checklist, Impact of Event Scale-Revised, and Trauma Symptom Checklist for Children. Highest professional degree, time since degree award, and student status yielded no differences in extent of reported trauma assessment test use.  相似文献   
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