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Cheyne H Dowding D Hundley V Aucott L Styles M Mollison J Greer I Niven C 《Midwifery》2008,24(2):199-213
OBJECTIVES: to describe the development and testing of an algorithm for diagnosis of active labour in primiparous women. DESIGN: qualitative and quantitative methods were used. A literature review was first conducted to identify the key cues for inclusion in the algorithm. Focus groups of midwives were then conducted to assess content validity, finally a vignette study assessed the inter-rater reliability of the algorithm. SETTING: midwives from two study sites were invited to participate. Data were collected during 2002 and 2003. PARTICIPANTS: midwives from the first site took part in the focus groups (n=13), completed vignettes (n=19), or both. Midwives from the second site then completed vignettes (n=17). FINDINGS: an algorithm, developed from the key informational cues reported in the literature, was validated in relation to content validity by the findings from the focus groups. Inter-rater reliability was tested using vignettes of admission case histories and was found to be moderate in the first test (K=0.45). However, after modifying the algorithm the kappa score was 0.86, indicating a high level of agreement. KEY CONCLUSIONS: diagnosis of labour may be straightforward on paper but is frequently problematic in practice. This may be because the diagnosis of labour is made in a high pressured environment where conflicting pressures of workload, limited resources and emotional pressures add to the complexity of the judgement. IMPLICATIONS FOR PRACTICE: we offer a valid and reliable decision-support tool as an aid for diagnosis of labour. The evaluation of the implementation of this tool is under way and will determine whether it is effective in reducing unnecessary admissions and improving clinical outcomes for women. 相似文献
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Experimental pullout testing and comparison of variables in transpedicular screw fixation. A biomechanical study 总被引:12,自引:0,他引:12
The specific objective of this investigation was to assess and compare the relative performance of four types of pedicular fixation screws currently in use. All screws were tested under similar conditions. The results obtained have permitted the authors to rank the various screws tested in terms of performance as follows: 1) the Steffee screw, 2) the AO screw, 3) the Howmedica screw, and 4) the Roy-Camille screw. While the considerable variability of the bone material is recognized, the screw performance is also influenced by the geometric variables of screw design; improvements in the pullout strength can be achieved by an increase in the major diameter of the screw; screw displacement before failure appears related to the screw pitch, where an increase in the pitch of the screw will increase the amount of displacement before failure; screw angulation was found to have little effect on the pullout strength, but may have an effect on the screw displacement and energy absorption before failure. 相似文献
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James D Chalmers 《Critical care (London, England)》2009,13(3):156-2
The past 15 years have seen major advances in our understanding of severity assessment in community-acquired pneumonia (CAP). Prognostic tools have been promoted to guide all major management decisions in CAP, including admission to the critical care unit. Several recent studies, including the study by Renaud and colleagues, have challenged us to re-evaluate how we consider severe CAP, a concept for which there is still no universally accepted definition. Existing severity scores such as the Pneumonia Severity Index and the CURB65 score are designed to predict 30-day mortality. As a result, they are heavily weighted by age and co-morbidity. They perform less well when predicting other outcomes such as requirement for ICU admission and are of limited use in the critical care environment. This commentary discusses recent attempts to develop useful severity criteria to guide the use of ICU resources in patients with severe CAP. 相似文献
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S. Y. Liong R. E. Dixon N. Chalmers A. Tavakoli T. Augustine S. O��Shea 《Abdominal imaging》2011,36(2):206-214
Whole organ vascularized pancreatic transplant is a recognized treatment for diabetes and is increasingly being performed
worldwide. The procedure itself is complex and is associated with significant mortality and morbidity. Despite improvements
in surgical techniques, postoperative complications of pancreatic transplantation are still common and include graft rejection,
pancreatitis, peripancreatic fluid collections, exocrine leaks, vascular thrombosis, and hemorrhage. In this pictorial essay,
we review clinical presentation and imaging features of these complications. We also briefly discuss technique and complications
of islet cell transplants. 相似文献