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In many cases of sporadic frontotemporal dementia (FTD) and in FTD caused by tau mutations (FTDP-17) there is disruption of the normal splicing of tau leading to the aberrant expression of tau isoforms and neurodegeneration. This suggests a central role for tau in the pathogenesis of FTD. However, more than half the cases of sporadic FTD show no tau deposition. We question whether altered expression is also involved in the pathogenesis of tau-negative FTD. Real-time polymerase chain reaction was used to investigate tau isoform expression in tau-negative FTD and age-matched controls. There were no differences in total tau mRNA or 4R versus 3R isoform expression. Our study suggests that perturbed tau mRNA expression is unlikely to be involved in the pathogenesis of tau-negative FTD.  相似文献   
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Background: The outcome of breast cancer is usuallydetermined by multiple factors. Serum tumor necrosis factoralpha concentration has been found to be increasedin the circulation of patients with malignancy. Thisstudy was designed with the aim to investigateany correlation between the serum tumor necrosis factoralpha and the clinicopathological fetures and furthermore evaluatethe prognostic significance of serum tumor necrosis factoralpha concentration in breast cancer. Methods: Forty consecutivepatients with invasive breast cancer undergoing modified radicalmastectomy were prospectively included and evaluated. Venous bloodsamples were collected before the surgery. Sera wereobtained by centrifugation, and stored at – 70°C until assayed. The control group consisted 30healthy, age-matched subjects. Serum concentrations of tumor necrosisfactor alpha were measured by the quantitative sandwichenzyme immunoassay technique. The data on tumor size,age, estrogen receptor status, lymph node status andTNM staging were reviewed and recorded.Results: The mean value of serum tumor necrosis factor alphain patients with invasive breast cancer was 1.47± 0.58 pg/ml and that of the controlgroup was 0.98 ± 0.37 pg/ml, and thedifference was significant (P < 0.01). With univariableanalysis, patients with maximum tumor size of 5cm or larger (P=0.03), more advancedTNM staging (P < 0.01); and more advancedlymph node status (P < 0.01) were shownto have significantly higher serum concentrations of tumornecrosis factor alpha. However, with multivariable analysis, TNMstaging appeared as the only independent factor (P< 0.01) predicting the significant, higher serum concentrationsof tumor necrosis factor alpha. Conclusion: Preoperative evaluationof serum tumor necrosis factor alpha concentrations maybe a valuable parameter for reflecting the severityof staging for invasive breast cancer.  相似文献   
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The relationship between quality of life (QOL) assessments and decision making, in relation to the delivery of health services, is subjected to critical appraisal. Three levels of decision making in the health care system are taken into account in the analysis. Criticisms of opinion polling provide the basis for the appraisal. Examples of criticisms considered are: Might the use of QOL information be manipulative? Could the interviews or questionnaires used to obtain QOL data influence personal opinions? Are the methods used sometimes defective and/or superficial? Will QOL information always be used in decision making in ways that are ascertainable and justifiable? It is concluded that the time has come for the main focus of critical appraisal in QOL research to shift, from an emphasis on evaluation of the quality of methods used for assessments of QOL, toward an emphasis on the practical usefulness of QOL data.  相似文献   
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The impact of multiple donor and recipient variables on functional survival of 307 cadaveric pancreas allografts transplanted in 253 recipients at the authors' institution between July 25, 1978 and September 4, 1990 was determined using the Cox proportional hazards regression model. Relative risk of graft loss was calculated for all cases as well as for technically successful (TS) ones. Factors with an impact in descending order of significance for TS cases were immunosuppression (RR = 3.9 for double-drug versus triple-drug maintenance, p less than 0.0001); recipient category (RR = 2.4 for pancreas alone versus simultaneous pancreas/kidney, p = 0.009); retransplantation (RR = 1.8 for retransplants versus primary grafts, p = 0.007); donor hyperglycemia (RR = 1.7 for blood glucose greater than or equal to 200 versus less than 200 mg/dL, p = 0.02); human leukocyte antigen (HLA) matching (RR = 2.1 for poor versus a good match, p = 0.04). A logistic regression analysis also was performed to determine which factors predisposed to technical failure; none were identified. To make the model as relevant as possible to their current program, the authors analyzed only the bladder-drained cases (n = 221; 1984 to 1990). All patients received triple therapy. Recipient category, retransplantation, donor hyperglycemia, and degree of HLA matching remained as significant risk factors. Construction of estimated survival curves showed that the results of retransplantation were significantly improved, and the penalty incurred by using hyperglycemic donors was partially ameliorated by using well-matched donors. Because preservation times up to 30 hours did not exert an adverse effect on outcome, an argument is made to share pancreata between centers to achieve good matches.  相似文献   
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A rare complete lateral dislocation of the thoracic spine with preservation of neurologic function is reported. Anatomic reduction was obtained using an anterior approach and Harrington distraction rods for reduction followed by a broad plate and subsequent posterior segmental fixation and fusion. Long-term followup showed an excellent result.  相似文献   
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