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Objective: To find the incidence of multicentric renal cell carcinoma and its possible relationship to the other clinical and pathologic findings. Methods: A total of 40 patients with renal cell carcinoma underwent radical nephrectomy between March 1994 and January 1996 at Hacettepe University, School of Medicine, Department of Urology. All of the materials were examined grossly and histologically by the same pathologist. Results: Among 40 kidneys 4 had satellite carcinoma (10%), 3 of them had been shown by preoperative imaging techniques, 1 was found histopathologically. Conclusion: If preoperative imaging techniques do not show additional lesion in the kidney besides the small early stage primary in incidentally discovered patients, the incidence of satellite renal cell carcinoma is low enough to justify nephron sparing surgery.  相似文献   
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Tissue microarrays (TMAs) represent a powerful method for undertaking large‐scale tissue‐based biomarker studies. While TMAs offer several advantages, there are a number of issues specific to their use which need to be considered when employing this method. Given the investment in TMA‐based research, guidance on design and execution of experiments will be of benefit and should help researchers new to TMA‐based studies to avoid known pitfalls. Furthermore, a consensus on quality standards for TMA‐based experiments should improve the robustness and reproducibility of studies, thereby increasing the likelihood of identifying clinically useful biomarkers. In order to address these issues, the National Cancer Research Institute Biomarker and Imaging Clinical Studies Group organized a 1‐day TMA workshop held in Nottingham in May 2012. The document herein summarizes the conclusions from the workshop. It includes guidance and considerations on all aspects of TMA‐based research, including the pre‐analytical stages of experimental design, the analytical stages of data acquisition, and the postanalytical stages of data analysis. A checklist is presented which can be used both for planning a TMA experiment and interpreting the results of such an experiment. For studies of cancer biomarkers, this checklist could be used as a supplement to the REMARK guidelines.  相似文献   
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Hyperglycemia (blood glucose concentration >150 mg/dL) is common in extremely low gestational age newborns (ELGANs; birth at <28 week gestation). Hyperglycemia increases the risk of brain injury in the neonatal period. The long‐term effects are not well understood. In adult rats, hyperglycemia alters hippocampal energy metabolism. The effects of hyperglycemia on the developing hippocampus were studied in rat pups. In Experiment 1, recurrent hyperglycemia of graded severity (moderate hyperglycemia (moderate‐HG), mean blood glucose 214.6 ± 11.6 mg/dL; severe hyperglycemia (severe‐HG), 338.9 ± 21.7 mg/dL; control, 137.7 ± 2.6 mg/dL) was induced from postnatal day (P) 3 to P12. On P30, the hippocampal neurochemical profile was determined using in vivo 1H MR spectroscopy. Dendritic arborization in the hippocampal CA1 region was determined using microtubule‐associated protein (MAP)‐2 immunohistochemistry. In Experiment 2, continuous hyperglycemia (mean blood glucose 275.3 ± 25.8 mg/dL; control, 142.3 ± 2.6 mg/dL) was induced from P2 to P6 by injecting streptozotocin (STZ) on P2. The mRNA expression of glycogen synthase 1 (Gys1), lactate dehydrogenase (Ldh), glucose transporters 1 (Glut1) and 3 (Glut3) and monocarboxylate transporters 1 (Mct1), 2 (Mct2) and 4 (Mct4) in the hippocampus was determined on P6. In Experiment 1, MRS demonstrated lower lactate concentration and glutamate/glutamine (Glu/Gln) ratio in the severe‐HG group, compared with the control group (p < 0.05). Phosphocreatine/creatine ratio was higher in both hyperglycemia groups (p < 0.05). MAP‐2 histochemistry demonstrated longer apical segment length, indicating abnormal synaptic efficacy in both hyperglycemia groups (p < 0.05). Experiment 2 showed lower Glut1, Gys1 and Mct4 expression and higher Mct1 expression in the hyperglycemia group, relative to the control group (p < 0.05). These results suggest that hyperglycemia alters substrate transport, lactate homeostasis, dendritogenesis and Glu‐Gln cycling in the developing hippocampus. Abnormal neurochemical profile and dendritic structure due to hyperglycemia may partially explain the long‐term hippocampus‐mediated cognitive deficits in human ELGANs.  相似文献   
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Purpose

To assess short- and long-term mortality and rebleeding with endoscopic cyanoacrylate (EC) versus balloon-occluded retrograde transvenous obliteration (BRTO).

Materials and Methods

A retrospective cohort comparison was conducted of 90 EC patients and 71 BRTO patients from 1997 through 2015 with portal hypertension who presented due to endoscopically confirmed bleeding cardiofundal gastric varices. Patients underwent either endoscopic intra-varix injection of 4-carbon-n-butyl-2-cyanoacrylate or sclerosis with sodium tetradecyl sulfate with balloon occlusion for primary variceal treatment.

Results

Seventy-one BRTO patients and 90 EC patients, of whom 89% had cirrhosis and 35% were women, were included, with a respective average Model for End-Stage Liver Disease (MELD) score of 13.4 and 14.4, respectively. Mortality at 6 weeks was 14.4% for EC patients and 13.1% for BRTO patients (Kaplan-Meier/Wilcoxon, P = .85). No long-term mortality difference was observed (Cox hazard ratio [HR] = 0.89, P = .64). Also, 5.1% of EC patients and 3.5% of BRTO patients (Kaplan-Meier/Wilcoxon, P = .62) rebled at 6 weeks, but at 1 year, 22.0% of EC patients and 3.5% of BRTO patients had rebled (Kaplan-Meier/Wilcoxon, P < .01). Lower rates of long-term rebleeding were found with BRTO (Cox HR = 0.25, P = .03). No difference was seen in the rate of new portal hypertensive complications (Cox HR = 1.21, P = .464). However, 16/71 patients who underwent BRTO had simultaneous transjugular intrahepatic portosystemic shunt. Age, sex, MELD score, and presence of cirrhosis were the primary predictors of mortality. One death in the EC group and 5 deaths in the BRTO group were deemed to be procedurally related (chi-square, P = .088).

Conclusions

BRTO is associated with a lower rate of rebleeding but no change in mortality.  相似文献   
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