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Intratumor heterogeneity is a main cause of the dismal prognosis of glioblastoma (GBM). Yet, there remains a lack of a uniform assessment of the degree of heterogeneity. With a multiscale approach, we addressed the hypothesis that intratumor heterogeneity exists on different levels comprising traditional regional analyses, but also innovative methods including computer-assisted analysis of tumor morphology combined with epigenomic data. With this aim, 157 biopsies of 37 patients with therapy-naive IDH-wildtype GBM were analyzed regarding the intratumor variance of protein expression of glial marker GFAP, microglia marker Iba1 and proliferation marker Mib1. Hematoxylin and eosin stained slides were evaluated for tumor vascularization. For the estimation of pixel intensity and nuclear profiling, automated analysis was used. Additionally, DNA methylation profiling was conducted separately for the single biopsies. Scoring systems were established to integrate several parameters into one score for the four examined modalities of heterogeneity (regional, cellular, pixel-level and epigenomic). As a result, we could show that heterogeneity was detected in all four modalities. Furthermore, for the regional, cellular and epigenomic level, we confirmed the results of earlier studies stating that a higher degree of heterogeneity is associated with poorer overall survival. To integrate all modalities into one score, we designed a predictor of longer survival, which showed a highly significant separation regarding the OS. In conclusion, multiscale intratumor heterogeneity exists in glioblastoma and its degree has an impact on overall survival. In future studies, the implementation of a broadly feasible heterogeneity index should be considered.  相似文献   
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Journal of Medical Ultrasonics - Chronic liver disease is still a major problem because disease progression will ultimately lead to liver cirrhosis. Portal hypertension is the hallmark in advanced...  相似文献   
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PurposeUnderstanding the value of genetic screening and testing for monogenic disorders requires high-quality, methodologically robust economic evaluations. This systematic review sought to assess the methodological quality among such studies and examined opportunities for improvement.MethodsWe searched PubMed, Cochrane, Embase, and Web of Science for economic evaluations of genetic screening/testing (2013-2019). Methodological rigor and adherence to best practices were systematically assessed using the British Medical Journal checklist.ResultsAcross the 47 identified studies, there were substantial variations in modeling approaches, reporting detail, and sophistication. Models ranged from simple decision trees to individual-level microsimulations that compared between 2 and >20 alternative interventions. Many studies failed to report sufficient detail to enable replication or did not justify modeling assumptions, especially for costing methods and utility values. Meta-analyses, systematic reviews, or calibration were rarely used to derive parameter estimates. Nearly all studies conducted some sensitivity analysis, and more sophisticated studies implemented probabilistic sensitivity/uncertainty analysis, threshold analysis, and value of information analysis.ConclusionWe describe a heterogeneous body of work and present recommendations and exemplar studies across the methodological domains of (1) perspective, scope, and parameter selection; (2) use of uncertainty/sensitivity analyses; and (3) reporting transparency for improvement in the economic evaluation of genetic screening/testing.  相似文献   
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黄嘉敏  赵霞  孙宜康  李宛莹  苟继周  周光德  何清 《肝脏》2022,27(1):20-22,37
目的了解何首乌致药物性肝损伤(Polygonum multiflorum-associated drug induce liver injury,PM-DILI)的临床病理学特点。方法收集2019年3月1日至2021年3月1日深圳市第三人民医院收治的8例PM-DILI患者临床资料。肝穿组织进行苏木素-伊红染色、网状纤维染色、Masson三色染色、铁、铜特殊染色和免疫组织化学染色,显微镜下观察分析。结果8例PM-DILI患者男女比为1∶1,平均年龄43岁,其中6例为急性PM-DILI,2例慢性为PM-DILI。入院血清学检查异常主要包括转氨酶升高和淤胆均为7例。主要组织病理学改变为点灶状坏死8例、界面炎5例、融合坏死4例,融合坏死以肝腺泡3带为主,不伴或伴少数炎细胞浸润;胆汁淤积5例,为肝腺泡3带的肝细胞、毛细胆管内淤胆,不伴或伴少数炎细胞浸润;中央静脉炎3例;病程长者可发生肝纤维化,甚至肝硬化2例。结论肝腺泡3带为主的急性淤胆和肝细胞坏死是PM-DILI主要组织学表现,严重者可发生静脉炎等血管损伤。  相似文献   
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