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991.
M.J. Jones A.S. Buchanan C.P. Neal A.R. Dennison M.S. Metcalfe G. Garcea 《Pancreatology》2013,13(4):436-442
BackgroundPancreatic cystic lesions are an increasing problem and investigation of these cysts can be fraught with difficulty. There is currently no gold standard for diagnosis or surveillance. This review was undertaken to determine the present reliability of the characterisation, assessment of malignant potential and diagnosis of pancreatic cystic lesions using available imaging modalities.MethodsA Medline search using the terms ‘pancreatic’, ‘pancreas’, ‘cyst’, ‘cystic’, ‘lesions’, ‘imaging’, ‘PET’. ‘CT’, ‘MRI’ and ‘EUS’ was performed. Publications were screened to include studies examining the performance of CT, MRI, MRCP, EUS and 18-FDG PET in the determination of benign or malignant cysts, cyst morphology and specific diagnoses.ResultsNineteen studies were identified that met the inclusion criteria. 18-FDG PET had a sensitivity and specificity of 57.0–94.0% and 65.0–97.0% and an accuracy of 94% in determining benign versus malignant cysts. CT had a sensitivity and specificity of 36.3–71.4% and 63.9–100% in determining benign disease but had an accuracy of making a specific diagnosis of 39.0–44.7%. MRI had a sensitivity and specificity of 91.4–100.0% and 89.7% in assessing main pancreatic duct communication.ConclusionCT is a good quality initial investigation to be used in conjunction with clinical data. MRCP can add useful information regarding MPD communication but should be used judiciously. PET may have a role in equivocal cases to determine malignancy. Further examination of CT-PET in this patient group is warranted. 相似文献
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Pediatric mastocytosis 总被引:2,自引:0,他引:2
Pediatric mastocytosis presents with heterogeneous cutaneous lesions and symptoms that are caused by increased numbers of tissue mast cells. In contrast with adult patients with mastocytosis, the course of pediatric patients is usually transient. Therefore, it has long been speculated that pediatric and adult mastocytosis may be based on different pathogenetic mechanisms. Indeed, new genetic findings now indicate differences in the pathogenesis. Adult patients usually express activating mutations of the growth factor receptor c-kit. Most children lack these mutations but sometimes carry other inactivating mutations of c-kit. Only children with progressive mastocytosis seem to express the activating mutations seen in adults. Causal treatment is not yet available, but H1 and H2 antihistamines may provide relief of symptoms. It is important to counsel patients and their parents carefully to avoid triggers that induce systemic mast cell degranulation. 相似文献
998.
Michael G. Jameson Shivani Kumar Shalini K. Vinod Peter E. Metcalfe Lois C. Holloway 《Radiotherapy and oncology》2014
Background and purpose
Contouring variation is a well know uncertainty in modern radiotherapy. This study investigates the relationship between contouring variation, tumor control probability (TCP) and equivalent uniform dose (EUD) for conformal non-small cell lung cancer (NSCLC) radiotherapy.Material and methods
Seven patients were retrospectively recruited to the study and multiple PTV contours were generated based on CT and PET imaging by three observers. Plans were created for each PTV volume. Volumes were analyzed geometrically using volume, location, dimension and conformity index (CI). Radiobiological plan analysis consisted of two TCP models and EUD. Spearman’s correlation coefficient (ρ) was used to quantify the association between geometric variation and radiobiological metrics.Results
The variation in CI and TCP for the study was 0.66–0.90% and 0.19–0.68%. Changes in lateral dimension and volume were significantly correlated with TCP and EUD with an average ρ of −0.49 and 0.43 (p < 0.01) respectively.Conclusions
TCP and geometric contour variation show significant correlation. This correlation was most significant for changes in lateral dimensions of PTV volumes. This association may be used in the assessment of contouring protocol violations in multicenter clinical trials and aid in the design of future contouring studies. 相似文献999.
A systematic review of the contribution of qualitative research to the study of quality of life in children and adolescents with epilepsy. 总被引:5,自引:0,他引:5
A sizeable literature focusing on QOL in children and adolescents with epilepsy has been produced over the last few years. However, relatively little emphasis has been placed on defining these issues from direct exploration of children's and adolescents' views. Qualitative methodologies are proposed in this review as an appropriate means of eliciting such information. This review systematically investigated the extent to which studies of QOL in children and adolescents with epilepsy have used recognised qualitative methodology. Articles for inclusion were identified by searching the term 'epilepsy', combined with 'adolescent(s) and/or child(ren)' and 'psychosocial and/or quality of life'. Selected articles were reviewed and rated using CASP Guidelines for qualitative research by two independent raters. Seventeen studies were retrieved through literature search. Of these six used some form of qualitative methodology either individually or combined with quantitative methods. However, only one study met quality criteria for selection in this systematic review. A summary of both selected and excluded studies is presented and methodological limitations discussed. Recommendations for appropriate methodology for investigation of QOL issues in children and adolescents are given. 相似文献
1000.
Sleep duration and mortality: The effect of short or long sleep duration on cardiovascular and all-cause mortality in working men and women 总被引:6,自引:0,他引:6
BACKGROUND: There is evidence to suggest that insufficient sleep may have an adverse effect on physical and psychological health. Previous studies have reported that when adjusting for major risk factors for cardiovascular disease and a number of demographic and social variables, sleeping 7-8 h each night is associated with lower mortality. These studies, however, have excluded any consideration of stress, which is known to be related to a number of behavioural risk factors for disease and, like sleep, may influence neurochemical, hormonal and immunological functioning. METHODS: This study revisits the associations between sleep duration, cardiovascular disease risk factors and mortality, taking into account the perceived stress of individuals. The data come from a cohort of working Scottish men and women recruited between 1970 and 1973; approximately half of the cohort was screened for a second time, 4-7 years after the baseline examination. RESULTS: For both men and women, higher self-perceived stress was associated with a reduction in the hours of sleep reported. The pattern of mortality from all causes and the pattern of mortality from cardiovascular disease were consistent for both men and women. When sleep was measured on one occasion only, the risk of dying was reduced for men sleeping more than 8 h in every 24 h compared with those sleeping 7-8 h over the same period. This was after adjustment had been made for age, marital status, social class, cardiovascular risk factors and stress. The risk of dying was increased for women sleeping less than 7 h in every 24 h compared with those sleeping 7-8 h over the same period, after similar adjustments. When the data from the 1st and 2nd screening were considered longitudinally, both men and women who reported that they slept less than 7 h on both occasions that they were questioned, had a greater risk of dying from any cause than those who had reported sleeping 7-8 h at both screenings, after adjusting for age, marital status, social class and stress. CONCLUSIONS: Short sleep over a prolonged period may be associated with an increased risk of mortality: men and women who reported sleeping fewer than 7 h in 24 on two occasions between 4 and 7 years apart, had greater risk of dying from any cause over a 25 year period than those who reported sleeping 7-8 h on both occasions that they were questioned. 相似文献