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331.
OBJECTIVE: The purpose of this article is to describe the imaging findings of extrahepatic spread of hepatocellular carcinoma (HCC). CONCLUSION: Detecting extrahepatic metastases in HCC is critical in determining the optimal treatment plan for patients. Identifying the presence of extrahepatic metastases in patients with advanced disease may eliminate unnecessary surgery, such as liver transplantation or partial hepatic resection, and help direct the appropriate therapy.  相似文献   
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OBJECTIVE: The purpose of this article is to illustrate the common locations of desmoid tumors (deep fibromatosis), complications of intra- and extraabdominal desmoids, and treatment-related changes in their imaging appearance. CONCLUSION: Desmoids are locally aggressive fibrous tumors with a tendency to recur. Desmoids can be intraabdominal, in the abdominal wall, or extraabdominal. Complications, such as compression or invasion of adjacent structures, and abscess formation can occur. Treatment options include observation, local treatment (surgery, radiotherapy), or systemic therapy (conventional chemotherapy, molecular targeted agents).  相似文献   
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OBJECTIVE: Though classically thought of as an osseous-based sarcoma of children and adolescents, it is important to recognize that approximately 20% of all cases of Ewing sarcoma family of tumors (ESFT) occur in patients older than 18 years, often with extraskeletal disease. Understanding the specific imaging features, manners of presentation, and patterns of behavior of ESFT is therefore important in all settings. CONCLUSION: This article presents the imaging findings of ESFT in the adult, with specific attention to extraskeletal manifestations.  相似文献   
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OBJECTIVE: Extrapulmonary small cell carcinoma (EPSCC) is a rare, aggressive neoplasm arising from virtually any organ. Numerous oncologic studies have addressed prognostic indicators and survival rates in EPSCC, however relatively little has been published regarding the imaging features and metastatic patterns of these uncommon tumors. This article provides a pictorial review of EPSCC in multiple organs, emphasizing the imaging appearance at presentation and the radiologic patterns of recurrence/metastasis. CONCLUSION: Although the appearance of EPSCC is often nonspecific, the typical presentation is large aggressive tumors that, similar to small cell carcinoma in the lung, often respond well to local therapy but tend to recur relentlessly at distant sites.  相似文献   
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Dunaliella bardawil is a carotenoid-producing alga that is being considered for use in nutraceuticals. To evaluate potential protective effects of consumption of this alga, rats were treated with two different doses of D. bardawil (2.5 and 5.0 g kg(-1) body weight [bw]) as a biomass suspension daily for 14 days. Animals were tested against Carbon tetrachloride (CCl4; 2 ml kg(-1))-induced liver toxicity as measured by various biochemical marker enzymes in liver and blood. All measurements were taken 6 h following the single dose of CCl4. The results of this study show that there was a slight, but statistically significant mean serum enzyme values, with D. bardawil treatment, compared to higher mean values in animals receiving CCl4 alone. Lipid peroxidation is measured by thiobarbituric acid-reactive substance (TBARS) activity was likewise slightly less elevated with algae treatment. The results also demonstrated protection against DNA strand breaks in hepatocytes, as measured by single cell gel electrophoresis. Liver histopathology was less severe with D. bardawil treatment, supporting the apparent protective action of 14-day treatment on hepatic oxidative injury.  相似文献   
336.
We previously demonstrated that spare respiratory capacity of the TCA cycle enzyme alpha-ketoglutarate dehydrogenase (KGDH) was completely abolished upon increasing levels of MAO-B activity in a dopaminergic cell model system (Kumar et al., J Biol Chem 278:46432–46439, 2003). MAO-B mediated increases in H2O2 also appeared to result in direct oxidative inhibition of both mitochondrial complex I and aconitase. In order to elucidate the contribution that each of these components exerts over metabolic respiratory control as well as the impact of MAO-B elevation on their spare respiratory capacities, we performed metabolic respiratory control analysis. In addition to KGDH, we assessed the activities and substrate-mediated respiration of complex I, pyruvate dehydrogenase (PDH), succinate dehydrogenase (SDH), and mitochondrial aconitase in the absence and presence of complex-specific inhibitors in specific and mixed substrate conditions in mitochondria from our MAO-B elevated cells versus controls. Data from this study indicates that Complex I and KGDH are the most sensitive to inhibition by MAO-B mediated H2O2 generation, and could be instrumental in determining the fate of mitochondrial metabolism in this cellular PD model system.  相似文献   
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Assigning a tumor grade to breast cancer provides important prognostic information and guides optimal therapy. The present study was undertaken to grade breast carcinoma on aspirates by Robinson grading (RGS) and Scarff-Bloom-Richardson grading system (SBR). Histological grading was done according to Nottingham modification of Scarff-Bloom-Richardson method and the two cytological grading systems were compared. Fifty cases of breast carcinoma with preoperative cytologic diagnosis were assigned tumor grade. Histologic grading was done on corresponding mastectomy or partially resected specimens. Statistical analysis was performed; correlation between cytologic and histologic grading was established using Spearman correlation coefficient. Regression analysis was done to assess the significance of each cytological feature. Univariate analysis showed strong correlation (P < 0.01) for all features except dissociation. Multiple regression analysis of cytologic features revealed cell dissociation nucleoli and nuclear margin as the most influential features. A concordance of 72.5% between RGS (cyto) and SBR (cyto), 64% for RGS (cyto) and SBR (histo), 82% for SBR (cyto) and SBR (histo) was noted. There was a significant association (P < 0.001) between the grades assigned to cytologic and histologic specimens. Cytologic grade could be used to predict histologic grade as significant relationship exists between grades assigned to cytologic and histologic specimens.  相似文献   
340.
The Syrian hamster has proved useful in the evaluation of therapeutics and vaccines for severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2). To advance the model for preclinical studies, we conducted serial sacrifice of lungs, large pulmonary vessels, and hearts from male and female Syrian hamsters for days 1–4, and 8 post-infection (dpi) following infection with a high dose of SARS-CoV-2. Evaluation of microscopic lung histopathology scores suggests 4 and 8 dpi as prime indicators in the evaluation of moderate pathology with bronchial hyperplasia, alveolar involvement and bronchiolization being key assessments of lung disease and recovery, respectively. In addition, neutrophil levels, red blood cell count and hematocrit showed significant increases during early infection. We present histological evidence of severe damage to the pulmonary vasculature with extensive leukocyte transmigration and the loss of endothelial cells and tunica media. Our evidence of endothelial and inflammatory cell death in the pulmonary vessels suggests endothelialitis secondary to SARS-CoV-2 epithelial cell infection as a possible determinant of the pathological findings along with the host inflammatory response. Lastly, pathological examination of the heart revealed evidence for intracardiac platelet/fibrin aggregates in male and female hamsters on 8 dpi, which might be indicative of a hypercoagulative state in these animals.  相似文献   
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