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991.
992.
Xuyuan Jiang Patrick Asbach Bernd Hamm Ke Xu Jan Banzer 《International journal of colorectal disease》2014,29(12):1541-1550
Purpose
The aim of this study was to investigate the diagnostic accuracy of MR enterography (MRE) for detection of distal ileal and colorectal inflammatory bowel disease (IBD) and to evaluate whether 3 T MRI can provide a higher diagnostic performance compared to 1.5 T.Methods
A retrospective review of patients with known or suspected IBD who underwent MRE and colonoscopy within 3 months was performed. For analysis, the bowel was divided into six segments. Compared with colonoscopy, the accuracy values for MRI diagnosis of overall and each magnetic field strength were calculated, and the differences between 1.5 T and 3.0 T were compared. The image quality was scored separately for both field strengths and compared.Results
Eighty-eight patients were included in the study. On a patient basis, MRE had an overall sensitivity of 92.1 % and specificity of 72.0 %. On a segment basis, the sensitivity and specificity were 79.1 % and 93.6 %, respectively. Concerning severely inflamed segments, per-segment sensitivity increased from 79.1 to 94.7 %. The comparison of accuracy values between the two field strengths showed no statistically significant difference. B1 homogeneity and overall artifacts were not significantly different between 3.0 T and 1.5 T imaging. Compared to colonoscopy, MRI found four more fistulas confirmed at subsequent surgery.Conclusions
MRI has a high diagnostic accuracy for detection of distal ileal and colorectal IBD. 3 T MRI can be considered equivalent but not superior compared to 1.5 T imaging in this context. In addition, our findings suggest MRE to be a valuable tool in detecting surgically relevant pathologies (fistulas) with higher accuracy than colonoscopy. 相似文献993.
Anne Schlesinger-Raab André L. Mihaljevic Silvia Egert Rebecca T. Emeny Karl-Walter Jauch Jörg Kleeff Alexander Novotny Natascha C. Nüssler Miriam Rottmann Wolfgang Schepp Wolfgang Schmitt Gabriele Schubert-Fritschle Bernhard Weber Christoph Schuhmacher Jutta Engel 《Journal of cancer research and clinical oncology》2014,140(5):789-800
Background
Gastric cancer accounts for 5 % of cancer deaths. Successful implementation of guideline-recommended treatment procedures should result in population-based outcome improvements despite the still poor prognosis. In this context, the objective of this study was to compare the outcome of gastric cancer by different levels of hospital care.Materials and methods
Total of 8,601 patients with invasive gastric cancer documented between 1998 and 2012 by the Munich Cancer Registry were evaluated. Tumour and therapy characteristics and outcome were analysed in regard to five levels of hospital care: three levels were defined for general hospitals (level I–III), while university hospitals and speciality hospitals were grouped as separate classes. Survival was investigated using the Kaplan–Meier-method, computing relative survival, and by multivariate Cox proportional hazard regression.Results
The average age differed between 66 years in university hospitals and 75 years in hospitals providing a basic level of care (level I). No survival differences were found for patients treated in different levels of hospital care in 75 % of the patient cohort, namely the M0 patients. A better survival could only be shown for patients with M1 at diagnosis when treated in a university or level III hospital compared to those treated in other hospitals.Conclusion
The outcome difference of M1 patients is most likely caused by selection effects concerning health status differences and not by processes of health care attributable to level of hospital care. Thus, this study demonstrates and confirms appropriate treatment and care of gastric cancer over all levels of hospital care. 相似文献994.
Claudia Ott Angela Takses Florian Obermeier Elisabeth Schnoy Bernd Salzberger Martina Müller 《International journal of colorectal disease》2014,29(11):1329-1338
Background
With the introduction of anti-TNF therapies in the treatment of IBD, the therapeutic strategies have changed to an accelerated step-up care to avoid long-term complications. Little is known about the implementation of these strategies into daily care. We aimed to evaluate this question and to identify factors associated with the early use of immunosuppressants or anti-TNF therapies in a population-based IBD cohort.Methods
Patients with an IBD diagnosed between January 2004 and December 2008 were included. Medical therapies were evaluated at first diagnosis and during a 5-year follow-up. Risk factors associated with the initiation of an immunosuppressive therapy were assessed.Results
Two hundred and forty-one patients were evaluated (145 Crohn’s disease (CD), 96 ulcerative colitis (UC)). An immunosuppressive or anti-TNF therapy was started in 83 CD (57.2 %) and 40 UC (43 %) patients (p?=?0.033, relative risks (RR) 1.77; 95 % confidence interval (CI) 1.05–3.0). After 5 years, 38.8 % CD patients on immunosuppressive therapy were treated with anti-TNF therapies. The use of corticosteroids at first diagnosis, disease localization and surgery were independent predictors for an immunosuppressive or anti-TNF therapy in CD. In UC, the extension of disease was associated with immunosuppressive therapies. The use of steroids and localization in CD patients and an extended disease in UC patients affected the time until an immunosuppressive therapy was started.Conclusion
We found a high proportion of patients using an immunosuppressive therapy during the early course. Therefore, the accelerated step-up strategy seems to be successfully implemented in the daily care of IBD patients. We were able to identify several factors associated with an immunosuppressive or anti-TNF therapy in CD and UC. 相似文献995.
Bernhard Hametner Siegfried Wassertheurer Alun D. Hughes Kim H. Parker Thomas Weber Bernd Eber 《International journal of cardiology》2014
Background
Analysis of the arterial pressure curve plays an increasing role in cardiovascular risk stratification. Measures of wave reflection and aortic stiffness have been identified as independent predictors of risk. Their determination is usually based on wave propagation models of the circulation. Another modeling approach relies on modified Windkessel models, where pressure curves can be divided into reservoir and excess pressure. Little is known of their prognostic value.Methods and results
The aim of this study is to evaluate the predictive value of parameters gained from reservoir theory applied to aortic pressure curves in a cohort of high-risk patients. Furthermore the relation of these parameters to those from wave separation analysis is investigated.Central pressure curves from 674 patients with preserved ejection fraction, measured by radial tonometry and a validated transfer function, were analyzed. A high correlation between the amplitudes of backward traveling pressure waves and reservoir pressures was found (R = 0.97). Various parameters calculated from the reservoir and excess pressure waveforms predicted cardiovascular events in univariate Cox proportional hazards modeling. In a multivariate model including several other risk factors such as brachial blood pressure, the amplitude of reservoir pressure remained a significant predictor (HR = 1.37 per SD, p = 0.016).Conclusions
Based on very different models, parameters from reservoir theory and wave separation analysis are closely related and can predict cardiovascular events to a similar extent. Although Windkessel models cannot describe all of the physiological properties of the arterial system, they can be useful to analyze its behavior and to predict cardiovascular events. 相似文献996.
997.
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999.
Diploid and triploid rainbow trout weighing approximately 3 g were either fed for five weeks, or feed deprived for one week, followed by refeeding. During feed deprivation gastrointestinal somatic index decreased in diploids, but not triploids, and during refeeding, carcass growth rate recovered more quickly in triploids. Although not affected by ploidy, liver ghr2 and igfbp2b expression increased and igfbp1b decreased in fasted fish. Effects of ploidy on gene expression indicate potential mechanisms associated with improved recovery growth in triploids, which include decreased hepatic igfbp expression, which could influence IGF-I bioavailability, differences in tissue sensitivity to TGFbeta ligands due to altered tgfbr and smad expression, and differences in expression of muscle regulatory genes (myf5, mstn1a, and mstn1b). These data suggest that polyploidy influences the expression of genes critical to muscle development and general growth regulation, which may explain why triploid fish recover from nutritional insult better than diploid fish. 相似文献