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41.
The Delphi technique is a method of collecting opinion on a particular research question. It is based on the premise that pooled intelligence enhances individual judgement and captures the collective opinion of a group of experts without being physically assembled. The conventional Delphi uses a series of questionnaires to generate expert opinion in an anonymous fashion and takes place over a series of rounds. The technique is becoming a popular strategy that straddles both quantitative and qualitative realms. Issues that are critical to its validity are the development of the questionnaire; definition of consensus and how to interpret non-consensus; criteria for and selection of the expert panel; sample size; and data analysis. The authors used the Delphi technique to assist with making recommendations regarding education and training for medical practitioners working in district hospitals in South Africa. The objective of this Delphi was to obtain consensus opinion on content and methods relating to the maintenance of competence of these doctors. They believe the experience gained from their work may be useful for other health science education researchers wishing to use the Delphi method. 相似文献
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Yarovaya N Schot R Fodero L McMahon M Mahoney A Williams R Verbeek E de Bondt A Hampson M van der Spek P Stubbs A Masters CL Verheijen FW Mancini GM Venter DJ 《Neurobiology of disease》2005,19(3):351-365
Sialin is a lysosomal membrane protein encoded by the SLC17A5 gene, which is mutated in patients with sialic acid storage diseases (SASD). To further understand the role of sialin in normal CNS development and in the progressive neuronal atrophy and dysmyelination seen in SASD, we investigated its normal cellular distribution in adult and developing mice. Overall, sialin showed granular immunoreactivity, consistent with a vesicular protein. Adult mice showed widespread sialin expression, including in the brain, heart, lung, and liver. High-level immunoreactivity was seen in the neuropil of the hippocampus, striatum, and cerebral cortex, as well as in the perikarya of cerebellar Purkinje cells, globus pallidus, and certain thalamic and brainstem nuclei. In mouse embryos, the highest levels of expression were observed in the nervous system. We discuss the possible role of sialin in normal development and in SASD pathogenesis, as a framework for further investigation of its function in these contexts. 相似文献
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This study investigated the effect of a backward training program on the physical and fitness condition of young women. Twenty-six healthy female university students (aged 18 - 23 years) took part in three different baseline tests: body composition, a submaximal treadmill test, and a 20-m shuttle run test. Subjects were divided into a training group (n = 13) and a control group (n = 13). The training group completed a six-week backward run/walk training program. The control group was restricted to their daily activities similar to the four weeks prior to the onset of the baseline tests. The training group showed a significant (p = 0.01) decrease in O(2) consumption during both submaximal forward and backward exercise on the treadmill (32 % decrease during backward and 30 % decrease during forward exercise). A significant (p = 0.01) decrease in percentage body fat (2.4 %), a 19.7 % decrease in the sum of skinfolds (p = 0.001) and significantly (p = 0.013) improved predicted VO(2max) values from the forward 20-m shuttle run test (5.2 %) were also found in the case of the training group. The findings suggest that backward walk/run training improves cardiorespiratory fitness for both forward and backward exercise and causes significant changes in body composition in young women. 相似文献
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Thirty-one viruses causing SAT-2 outbreaks in seven West African countries between 1974 and 1991, and four viruses representative of East and Central Africa were genetically characterized in this study. Four major viral lineages (I-IV) were identified by phylogenetic analysis of an homologous 480 nucleotide region corresponding to the C-terminus end of VP1. Lineage I comprised two West African genotypes with viruses clustering according to year of isolation rather than geographical origin. Lineage II was represented by viruses isolated between 1979 and 1983 in two neighbouring West African countries, Senegal and The Gambia. Viruses from Nigeria and Eritrea, representative of West and East Africa respectively, constituted lineage III, whilst lineage IV, comprising viruses from Central and East Africa, was regionally and genetically distinct. This study revealed that unrestricted animal movement in West Africa is a major factor in disease dissemination and has also provided the first indication of trans-regional virus transmission. 相似文献
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This report describes a case of bacteraemia caused by Anaerobiospirillum succiniciproducens. Anaerobiospirillum succiniciproducens is a rare cause of bacteraemia in humans, and when encountered usually occurs in immunocompromised patients. The organism is an anaerobic, spiral shaped, Gram negative bacillus with bipolar tufts of flagella. In this report, the morphology, with special reference to electron microscopic features, culture characteristics, and antimicrobial susceptibility are described. 相似文献
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The concept regarding esophageal squamous metaplasia, its existence, origin and the role it plays in the etiology of esophageal carcinoma, needs some urgent attention. Explanations regarding the presence of metaplastic squamous epithelial cells on esophageal smears, from asymptomatic high-risk patients undergoing screening for esophageal carcinoma, are difficult to find. The presence of squamous metaplastic cells on smears from the esophagus collected by us since 1983, from rural Transkei populations, is a regular finding and warrants some discussion. Cellular material from the esophageal lumen is collected with a gelatine encapsulated sponge brush for cytological evaluation. Each full-length, 'blind' sampling procedure produces a mixture of single cells, sheets, small groups as well as microbiopsies. Some very well preserved and excellent examples of esophageal epithelium undergoing or in a state of squamous metaplasia are a regular find. 相似文献
50.
Cui JS Spurdle AB Southey MC Dite GS Venter DJ McCredie MR Giles GG Chenevix-Trench G Hopper JL 《Genetic epidemiology》2003,24(3):161-172
Various statistical methods have been proposed to evaluate associations between measured genetic variants and disease, including some using family designs. For breast cancer and rare variants, we applied a modified segregation analysis method that uses the population cancer incidence and population-based case families in which a mutation is known to be segregating. Here we extend the method to a common polymorphism, and use a regressive logistic approach to model familial aggregation by conditioning each individual on their mother's breast cancer history. We considered three models: 1) class A regressive logistic model; 2) age-of-onset regressive logistic model; and 3) proportional hazards familial model. Maximum likelihood estimates were calculated using the software MENDEL. We applied these methods to data from the Australian Breast Cancer Family Study on the CYP17 5'UTR T-->C MspA1 polymorphism measured for 1,447 case probands, 787 controls, and 213 relatives of case probands found to have the CC genotype. Breast cancer data for first- and second-degree relatives of case probands were used. The three methods gave consistent estimates. The best-fitting model involved a recessive inheritance, with homozygotes being at an increased risk of 47% (95% CI, 28-68%). The cumulative risk of the disease up to age 70 years was estimated to be 10% or 22% for a CYP17 homozygote whose mother was unaffected or affected, respectively. This analytical approach is well-suited to the data that arise from population-based case-control-family studies, in which cases, controls and relatives are studied, and genotype is measured for some but not all subjects. 相似文献