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31.
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   
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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   
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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   
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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   
38.
Williams syndrome is a complex developmental disorder that results from the heterozygous deletion of a approximately 1.6-Mb segment of human chromosome 7q11.23. These deletions are mediated by large (approximately 300 kb) duplicated blocks of DNA of near-identical sequence. Previously, we showed that the orthologous region of the mouse genome is devoid of such duplicated segments. Here, we extend our studies to include the generation of approximately 3.3 Mb of genomic sequence from the mouse Williams syndrome region, of which just over 1.4 Mb is finished to high accuracy. Comparative analyses of the mouse and human sequences within and immediately flanking the interval commonly deleted in Williams syndrome have facilitated the identification of nine previously unreported genes, provided detailed sequence-based information regarding 30 genes residing in the region, and revealed a number of potentially interesting conserved noncoding sequences. Finally, to facilitate comparative sequence analysis, we implemented several enhancements to the program, including the addition of links from annotated features within a generated percent-identity plot to specific records in public databases. Taken together, the results reported here provide an important comparative sequence resource that should catalyze additional studies of Williams syndrome, including those that aim to characterize genes within the commonly deleted interval and to develop mouse models of the disorder.  相似文献   
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Vaccination of BALB/c mice with Leishmania major promastigote culture filtrate proteins plus Corynebacterium parvum confers resistance to infection with L. major. To define immunogenic components of this protein mixture, we used sera from vaccinated mice to screen an L. major amastigote cDNA expression library. One of the immunoreactive clones thus obtained encoded a novel protein of L. major with a molecular mass of 22.1 kDa. The predicted amino acid sequence of this clone exhibited significant homology to eukaryotic thiol-specific-antioxidant (TSA) proteins. Therefore, we have designated this protein L. major TSA protein. Southern blot hybridization analyses indicate that there are multiple copies of the TSA gene in all species of Leishmania analyzed. Northern blot analyses demonstrated that the TSA gene is constitutively expressed in L. major promastigotes and amastigotes. Recombinant TSA protein containing an amino-terminal six-histidine tag was expressed in Escherichia coli with the pET17b system and was purified to homogeneity by affinity chromatography. Immunization of BALB/c mice with recombinant TSA protein resulted in the development of strong cellular immune responses and conferred protective immune responses against infection with L. major when the protein was combined with interleukin 12. In addition, recombinant TSA protein elicited in vitro proliferative responses from peripheral blood mononuclear cells of human leishmaniasis patients and significant TSA protein-specific antibody titers were detected in sera of both cutaneous-leishmaniasis and visceral-leishmaniasis patients. Together, these data suggest that the TSA protein may be useful as a component of a subunit vaccine against leishmaniasis.  相似文献   
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