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31.
Plate fixation of open fractures of the tibia   总被引:2,自引:0,他引:2  
The results of immediate plate fixation of 97 open fractures of the tibial shaft in 95 patients are reported. Significant joint stiffness occurred in 11.4% and angular malunion of greater than 5 degrees in any plane was seen in 3.1%. The infection rate was 10.3%. However, even in those cases which develop delayed union or other complications, plate fixation of open fractures can produce excellent recovery of limb function.  相似文献   
32.
Planar imaging with a gamma camera is currently limited by the performance of the collimator. Spatial resolution and sensitivity trade off against each other; it is not possible with conventional parallel-hole collimation to have high geometric sensitivity and at the same time excellent spatial resolution unless field-of-view is sacrificed by using fan- or cone-beam collimators. We propose a rotating slit-collimator which collects one-dimensional projections from which the planar image may be reconstructed by the theory of computed tomography. The performance of such a collimator is modelled by Monte Carlo methods and images are reconstructed by a convolution and backprojection technique. The performance is compared with that of a conventional parallel-hole collimator and it is shown that higher spatial resolution with increased sensitivity is possible with the slit-collimator. For a point source a spatial resolution of some 6 mm at a distance of 100 mm from the collimator with a x7 sensitivity compared with a parallel-hole collimator was achieved. Applications to bone scintigraphy are modelled and an improved performance in hot-spot imaging is demonstrated. The expected performance in cold-spot imaging is analytically investigated. The slit-collimator is not expected to improve cold-spot imaging. Practical design considerations are discussed.  相似文献   
33.
This work presents the first sodium MRI functional renal study on a mouse model. The tissue sodium concentration was monitored during induced diuresis with furosemide. By using density-weighted chemical shift imaging (DWCSI) at high field strength a temporal resolution of less than 5 min for three dimensional (3D) data sets with high spatial resolution was achieved. A maximum increase of 20% in the cortex and a decrease of 45% of the original signal strength in the medulla were observed. These findings correspond well with experiments conducted on much larger rodent models.  相似文献   
34.
Transplant data: sources, collection and research considerations, 2004   总被引:9,自引:9,他引:0  
The process of collecting and analyzing transplant data is complex. Familiarity with how these data are collected is crucial to a thorough understanding of the information. This article focuses on available OPTN-SRTR data and the continuing evolution of data collection mechanisms; how that data collection system is improving the data quality and reducing the data collection burden; how additional ascertainment of outcomes both completes and validates existing data; and caveats that remain for researchers. This year's article focuses further on research considerations related to cohort choice, timing of data submission, and potential biases in follow-up data. Ongoing improvements in data collection timeliness and scope are covered. The impact of extra ascertainment of outcomes, particularly for post-transplant kidney graft failure from Medicare data, are also examined. A section on graft failure reporting among different sources traces the steps by which the SRTR reconciles different data sources in its analyses. It is important that those reading and conducting transplant research understand the origin, structure, and scope of the available data. All of these issues should be carefully considered when choosing cohorts and data sources for analysis.  相似文献   
35.
The objective of the study was to conduct a process and outcomes evaluation of the International AIDS Conference (IAC). Reaction evaluation data are presented from a delegate survey distributed at the 2004 IAC held in Thailand. Input and output data from the Thailand IAC are compared to data from previous IACs to ascertain attendance and reaction trends, which delegates benefit most, and host country effects. Outcomes effectiveness data were collected via a survey and intercept interviews. Data suggest that the host country may significantly affect the number and quality of basic science IAC presentations, who attends, and who benefits most. Intended and executed HIV work‐related behavior change was assessed under 9 classifications. Delegates who attended 1 previous IAC were more likely to report behavior changes than attendees who attended more than 1 previous IAC. The conference needs to be continually evaluated to elicit the required data to plan effective future IACs.  相似文献   
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Pulmonary embolism is a potentially lethal complication among patients with acetabular fractures requiring surgery. The reliability, safety, and extent of efficacy of pharmacologic as well as existing nonpharmacologic anticoagulation prophylaxis in this patient group has not been determined. A careful analysis of the myriad factors acting on these patients who have had major trauma and have undergone a major surgical procedure about the hip prompted a change in our approach to prophylaxis in this patient group. In the period from March 1984 through October 1987, 51 patients having 52 acetabular fractures underwent osteosynthesis at the Wake Forest University Medical Center. Twenty-four patients had two or more identifiable risk factors and underwent insertion of a Greenfield filter for prevention of pulmonary emboli. Filters were inserted at the time of acetabular surgery with C-arm guidance via the internal jugular vein approach. The average time for insertion was 57 min. Placements were verified by plain roentgenograms. There were no complications during filter insertion. Four patients with filters (17%) developed leg edema; in three the edema was minor, and in one the filter trapped what could have been a fatal embolus but caused lower extremity venous stasis severe enough to result in peripheral lower extremity tissue loss. There were no pulmonary emboli (by clinical criteria). The remaining 27 patients had routine medical prophylaxis and no filters. In this group, two patients had a clinically evident pulmonary embolus (7%), and one of these patients died. Two other patients (7%) had minor chronic leg edema. In one of them, a proximal deep venous thrombosis in the lower extremity was documented with venography, requiring rehospitalization and anticoagulant therapy.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
39.
Milk and orange juice (OJ) fortified with calcium-citrate-malate (CCM; calcium-citrate-malate salt is a coined term to describe a trademarked calcium delivery system found only in Citrus Hill Plus Calcium) were evaluated for their potential to alter urine chemistries and crystallization during the course of an eleven week, crossover study. Six male and six female, non-stone-forming, idiopathic hypercalciuric adults consumed 600 mg per day as beverage calcium for four consecutive weeks. The results show that both milk and CCM-fortified OJ (CCM-OJ) were well tolerated by male and female hypercalciurics since few significant changes occurred in overall urinary chemistry profiles. CCM-OJ did, however, significantly (P less than or equal to 0.05) increase urinary pH relative to milk in both sexes and urinary citrate concentration in women only. Both of these urinary parameters were significantly increased by CCM-OJ in both sexes relative to the basal period. The combined pH and citrate effects are recognized to protect against calcium oxalate stone formation through formation of the soluble calcium citrate salt. These data indicate that either milk or CCM-fortified orange juice can be consumed, at least within the limits tested, as a dietary source of calcium without increasing the risk of stone formation in a calcium-sensitive subpopulation. That the urine chemistries and crystallization of such calcium-sensitive individuals does not significantly change with the consumption of either beverage implies that the urine of normal individuals would be exceedingly unlikely to change as well.  相似文献   
40.
Communications among staff and patients on a stroke rehabilitation ward form the focus of this article, which reports on some aspects of a larger study using a grounded theory approach. Tape-recorded interviews were transcribed and analysed concurrently according to recommendations for the approach. A main theme entitled building a relationship was identified, and this process was found to occur in a context varying from participative at one end of a continuum to hierarchical at the other. Building a relationship was found to be influenced by role, personal qualities and organizational context. Appropriate relationships between role-holders were subject to negotiation, leading to a resulting congruence or incongruence between participants' expectations of each other and their roles. Personal qualities were brought into play in the process, with patients' views of staff and staff views of patients both being influential. Some of these views seemed to parallel what has been described in earlier literature as ‘the sick role’ and the labelling of patients as ‘good’ or ‘bad’. Responses to personal qualities led to nurses ascribing meaning to patients' behaviour in terms of adjustment to their stroke, giving time to them to help them to adjust, and withdrawal and handing over to other staff if this strategy failed. Organizational context also had an influence on building a relationship, with time constraints being identified particularly by nurses, and the need to fit in the most essential aspects of care. Place was also important, in that nurses were confined to the ward as a work location, whereas other therapists and doctors worked in other places and sometimes had the facility to take patients off the ward to concentrate on therapy. The findings are discussed against the background of related literature and the conclusion is drawn that the crucial role of nurses in rehabilitation is not recognized and valued, and that shortages of resources - especially suitably qualified and trained nursing staff- are a negative influence on building the relationships which are vital to successful rehabilitation.  相似文献   
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