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The aim of this study was to determine the ability of multiparametric MRI to identify the early effects of individual treatment, during combined chemo‐radiotherapy on brain tumours. Eighty male rats bearing 9L gliosarcomas were randomized into four groups: untreated, anti‐angiogenic therapy (SORA group), microbeam radiation therapy (MRT group) and both treatments (MRT+SORA group). Multiparametric MRI (tumour volume, diffusion‐weighted MR imaging (ADC), blood volume fraction (BVf), microvessel index (VSI), vessel wall integrity (AUCP846) and tissue oxygen saturation (StO2)) was performed 1 day before and 2, 5 and 8 days after treatment initiation. Unpaired t‐tests and one‐way ANOVA were used for statistical analyses. Each MR parameter measured in our protocol was revealed to be sensitive to tumour changes induced by any of the therapies used (individually or combined). When compared with untreated tumours, SORA induced a decrease in BVf, VSI, StO2 and AUCP846, MRT generated an increase in ADC and AUCP846 and combined therapies yielded mixed effects: an increase in ADC and AUCP846 and a decrease in BVf, StO2 and AUCP846. MRT and MRT+SORA significantly slowed tumour growth. Despite these two groups presenting with similar tumour sizes, the information yielded from MR multiparameter assessment indicated that, when used concomitantly, each therapy induced distinguishable and appreciable physiological changes in the tumour. Our results suggest that multiparametric MRI can monitor the effects of individual treatments, used concomitantly, on brain tumours. Such monitoring would be useful for the detection of tumour resistance to drug/radiotherapy in patients undergoing concomitant therapies. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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ObjectivesThis study sought to evaluate the impact of poststent optical coherence tomography (OCT) findings, including severe malapposition, on long-term clinical outcomes.BackgroundSuboptimal OCT findings following percutaneous coronary intervention (PCI) are highly prevalent; however, their clinical implications remain controversial.MethodsOf the patients registered in the Yonsei OCT registry, a total of 1,290 patients with 1,348 lesions, who underwent OCT immediately poststenting, were consecutively enrolled for this study. All patients underwent implantation of drug-eluting stents. Poststent OCT findings were assessed to identify predictors of device-oriented clinical endpoints (DoCE), including cardiac death, target vessel-related myocardial infarction (MI) or stent thrombosis, and target lesion revascularization (TLR). Significant malapposition criteria associated with major safety events (MSE) were also investigated, such as cardiac death, target vessel-related MI, or stent thrombosis.ResultsThe median follow-up period was 43.0 months (interquartile range [IQR] 21.4 to 56.0 months). The incidence rates of stent edge dissection, tissue prolapse, thrombus, and malapposition after intervention were not associated with occurrence of DoCE. However, patients with significant malapposition (total malapposition volume [TMV] ≥7.0 mm3] exhibited more frequent MSE. A smaller minimal stent area (MSA) was identified as an independent predictor for DoCE (hazard ratio [HR]: 1.20 [95% confidence interval [CI]: 1.00 to 1.43]; p = 0.045). Malapposition with TMV ≥7.0 mm3 was found to be an independent predictor of MSE (HR: 6.12 [95% CI: 1.88 to 19.95]; p = 0.003). Follow-up OCT at 3, 6, or 9 months after PCI showed that poststent TMV ≥7.0 mm3 was related to a greater occurrence of late malapposition and uncovered struts.ConclusionsAlthough most suboptimal OCT findings were not associated with clinical outcomes, a smaller MSA was associated with DoCE, driven mainly by TLR, and significant malapposition with TMV ≥7.0 mm3 was associated with more MSE after PCI. (Yonsei OCT [Optical Coherence Tomography] Registry for Evaluation of Efficacy and Safety of Coronary Stenting; Yonsei OCT registry; NCT02099162)  相似文献   
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ObjectivesThe aims of this study were to describe trends and hospital variation in same-day discharge following elective percutaneous coronary intervention (PCI) and to evaluate the association between trends in same-day discharge and patient outcomes.BackgroundInsights on contemporary use of same-day discharge following elective PCI are limited.MethodsIn a sequential cross-sectional analysis of 819,091 patients undergoing elective PCI at 1,716 hospitals in the National Cardiovascular Data Registry CathPCI Registry from July 1, 2009, to December 31, 2017, overall and hospital-level trends in same-day discharge were assessed. Among the 212,369 patients who linked to Centers for Medicare and Medicaid Services data, the association between same-day discharge and 30-day mortality and rehospitalization was assessed.ResultsA total of 114,461 patients (14.0%) were discharged the same day as PCI. The proportion of patients with same-day discharge increased from 4.5% in the third quarter of 2009 to 28.6% in the fourth quarter of 2017. From 2009 to 2017, the rate of same-day discharge increased from 4.3% to 19.5% for femoral-access PCI and from 9.9% to 39.7% for radial-access PCI. Hospital-level variation in the use of same-day discharge persisted throughout (median odds ratio adjusted for year and radial access: 4.15). Risk-adjusted 30-day mortality did not change over time, while risk-adjusted rehospitalization decreased over time and more quickly for same-day discharge (P for interaction <0.001).ConclusionsIn the past decade, a large increase in the use of same-day discharge following elective PCI was not associated with worse 30-day mortality or rehospitalization. Hospital-level variation in same-day discharge may represent an opportunity to reduce costs without compromising patient outcomes.  相似文献   
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