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Medical literature and vena cava filters: so far so weak   总被引:14,自引:0,他引:14  
Girard P  Stern JB  Parent F 《Chest》2002,122(3):963-967
STUDY OBJECTIVE: With the development of percutaneous inferior vena cava (IVC) filters, IVC interruption has become a widely used procedure in patients with or at risk for venous thromboembolism. In an attempt at clarifying the indications for filter placement, a systematic literature review was undertaken. DESIGN: Bibliographic search and analysis. MEASUREMENTS AND RESULTS: A systematic MEDLINE search about vena cava filters produced a total of 568 references with abstracts between 1975 and 2000 inclusively. Each reference was analyzed according to predetermined criteria. Nearly two thirds (65.0%) of these publications were retrospective studies or case reports (33.3 and 31.7%, respectively), 12.9% were animal or in vitro studies, 7.4% were prospective studies, 6.7% were reviews, and 8.1% reported on miscellaneous related topics. Among the prospective studies, only 16 studies included > or = 100 patients, only 1 study was a randomized controlled trial (0.02% of 568 references), and heterogeneity among series precluded any relevant comparison. In a similar search about heparin and venous thromboembolism, 47.4% of 531 references were randomized controlled trials. CONCLUSIONS: Until more relevant data become available, literature reviews about vena cava filters will remain narrative, and many if not most indications for filter placement will remain a matter of opinion.  相似文献   
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Dear editor, Radiotherapy is a cornerstone in the management of anal or rectal cancer. Because elderly patients are often excluded from clinical trials, little is known about radi-otherapy's therapeutic index (efficacy/toxicity ratio) in the geriatric population [1]. Still, the ageing of popula-tion imposes the challenge to treat older cancer patients and probably to adjust their treatment [2]. A few studies reported data on radiation-induced toxicities in nonage-narian patients, but data on efficacy are still scarce.  相似文献   
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Three groups of subjects, an idiot-savant group, a group of mentally handicapped subjects matched for IQ, and normal artistically gifted children, were compared for their recognition and graphic reproduction abilities. It was found that, independent of input modality, level of intelligence determined recognition performance, while graphic ability independent of IQ was the determining factor in reproduction accuracy.  相似文献   
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BACKGROUND: The number of proteins with mutations resulting in amyloidosis has continued to increase. Five proteins--transthyretin, fibrinogen alpha-A chain, apolipoprotein AI, lysozyme, apolipoprotein AII, cystatin C and gelsolin--can be associated with hereditary amyloidosis involving the kidney. METHODS: A French family with a history of autosomal dominant hereditary amyloidosis with early sicca syndrome and nephropathy leading to renal failure after the fifth to the seventh decade was studied. Several tissue specimens obtained from the proband and his relatives were examined. Immunohistochemistry was performed on paraffin embedded sections using the indirect immunoperoxidase technique. We searched for mutations in the five exons and flanking introns of the lysozyme gene. RESULTS: Amyloid deposits from the bowel, labial salivary gland and kidney were intensively stained by anti-lysozyme antibody. Sequence analysis of lysozyme exon 2 from the affected individuals revealed a nucleotide substitution predicting a substitution of the amino acid at position 64 in the mature protein from tryptophane, an aromatic residue to the cationic residue arginine (W64R). CONCLUSION: We report a novel mutation (W64R) of the lysozyme that is associated with hereditary amyloidosis and prominent nephropathy. Since the treatment of hereditary amyloidosis greatly varies with the nature of the amyloid protein, thorough characterization of the latter is crucial for the management of the disease.  相似文献   
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BACKGROUND: Although myocardial injury during cardiac surgery is associated with impaired clinical outcome, little is known about the prognostic value of cardiac troponin I (cTnI), a cardiac-specific biologic marker. The purpose of this prospective study was to evaluate the prognostic value of cTnI concentrations measured 20 h after the end of surgery in adult patients undergoing coronary artery bypass grafting or conventional valve surgery. METHODS: Baseline and perioperative characteristics of 502 consecutive patients undergoing conventional heart surgery during a 1-yr period were collected. In-hospital death (n = 28) and major clinical outcomes, e.g., low cardiac output, ventricular arrhythmia, and renal failure, were recorded. RESULTS: Multivariate analysis, using a stepwise logistic regression, showed that cTnI concentration was an independent predictor of in-hospital mortality (for cTnI concentration > 13 ng/ml, odds ratio = 6.7 [95% confidence interval, 2.3-19.3]), as were diabetes, altered preoperative cardiac function, emergent surgery, cardiopulmonary bypass duration, postoperative Pao2 level and total chest drainage volume. Further, elevated cTnI concentrations were associated with a cardiac cause of death and with major clinical outcomes. CONCLUSIONS: Our results demonstrated that cTnI concentration measured 20 h after the end of surgery is an independent predictor of in-hospital death after cardiac surgery. In addition, elevated concentrations of cTnI are associated with a cardiac cause of death and with major postoperative complications.  相似文献   
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OBJECTIVE: This study examines psychometric properties of a community activation assessment scale used for the evaluation of the Quebec project within the Federal Provincial Heart Health Initiative. The scale is composed of three sub scales, one for each of the intervention target risk factors. METHODS: Data were collected by telephone interviews conducted with 199 key informants from the 24 communities of the project. Reliability was studied using Cronbach's alpha coefficients and intraclass correlations. Validity was explored with factor analysis techniques. RESULTS: Subscales' internal consistency were very good, ranging from 0.71 to 0.83, but intraclass correlations between informants from the same communities were low. Factor analyses indicated a unidimensional structure for each scale. INTERPRETATION: These results show that the scale seems to provide reasonable assessments of the opinion of key informants regarding activation in their community. However, ranking communities based on the aggregated scores from local key informants may lead to classification problems.  相似文献   
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