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排序方式: 共有231条查询结果,搜索用时 234 毫秒
61.
Here we report a case of administration of defibrotide in an 11 months old infant with hepatic veno-occlusive disease during chemotherapy for nephroblastoma. He presented with abdominal distension, a weight gain of 15%, ascites, hepatomegaly with right upper quadrant pain, thrombocytopenia and hypertransaminasemia. Despite therapy, his clinical conditions aggravated, and, therefore intravenous administration of defibrotide on a compassionate-use basis was started. The dosage was 15?mg/kg/day in 4 divided doses, which was increased gradually (in 3 days) to 40?mg/kg/day in 4 divided doses. Defibrotide proved safe and effective in resolving clinical symptoms and normalizing serological findings in the syndrome.  相似文献   
62.
Relative differences in tubule density of the primary tumors have been suggested to be prognostically useful in nephroblastoma (Wilms tumor). Forty cases from our institution were retrospectively graded according to tubule density. There were significant differences in disease-free survivals between histologic grades. When compared to other clinical and pathologic staging criteria, tubule density was not more useful prognostically than the staging systems tested. However, when used in conjunction with clinical or pathologic stage, tumor grade improved prognostic sensitivity. Regardless of grade or stage, patients less than 24-months-old at diagnosis had better disease-free survival.  相似文献   
63.
Using the expression-profiling method, we identified nephroblastoma overexpressed gene (NOV) mRNA as one member of the mRNA population that was upregulated in cultured activated hepatic stellate cell (HSC). Northern analysis showed that NOV mRNA was increasingly expressed during progressive activation of cultured rat HSCs, and a significant increase was observed in both the carbon tetrachloride-induced and bile duct ligation/scission rat models of liver fibrosis. RT-PCR showed human NOV mRNA was increased in most fibrotic livers compared with normal livers. The expression of NOV protein in fibrotic rat and human livers was predominantly located in areas of ductular proliferation and HSC of the fibrous septa. HSCs stimulated with transforming growth factor beta1 showed increased expression of NOV protein without changing its mRNA levels. Dexamethasone stimulated the expression of NOV mRNA and protein. Furthermore, we demonstrated that bile acids have a modulating effect on the induction of NOV mRNA expression. In conclusion, this study suggests that NOV is expressed during liver fibrogenesis and HSCs may be an important source of hepatic NOV.  相似文献   
64.
Kidney development involves a series of complex interactions between the ureteric bud and undifferentiated mesenchyme, resulting in the production of the nephron unit. Among locally derived soluble factors, a particular relevance has been recognized to glial cell line-derived neurotrophic factor (GDNF) and neurturin (NTN) for the mesenchyme-to-epithelial conversion of a metanephron. Nephroblastoma is a developmental tumor of the kidney deriving from metanephric blastema that mimics renal development and may offer an adequate model of human nephrogenesis. We investigated the immunohistochemical expression of GDNF, NTN, and their receptors (GFR1, 2, and 3, and Ret) in normal human kidney and in 42 nephroblastomas, 20 of which were associated with nephrogenic rests (group A) and 22 were not (group B). We compared the immunostaining pattern in group A vs. group B and correlated clinical course with stage, grade, presence of nephrogenic rests, and immunohistochemical findings. GDNF, NTN, and their receptors were expressed in mature kidney and in 67% (GDNF) and 33% (NTN) of tumors, particularly in the epithelial component; precursor lesions were negative. No significant differences of expression were observed between groups A and B tumors. Low stage (P = 0.012), absence of nephrogenic rests (P = 0.016), intense expression of GDNF (P = 0.034), and NTN (P = 0.05) were associated with a more favorable outcome. Besides inductive activity in nephrogenesis, GDNF and NTN may play a role in maintaining differentiation and survival functions in mature kidney and may contribute to induce differentiation of nephroblastoma cells toward the less aggressive epithelial component. The pathway of activation seems to follow an autocrine/paracrine mechanism, as neurotrophic factors, GFR1-2-3 receptors and Ret are coexpressed.  相似文献   
65.
PURPOSE: CD44 is a group of transmembranous glycoproteins formed by alternative splicing of a single messenger RNA. An abnormal pattern of CD44 expression has been demonstrated in several human malignancies. We evaluate the prognostic value of standard CD44 (CD44s) and some of its isoforms in treating clinical Wilms tumor. MATERIALS AND METHODS: The immunohistochemical expression of CD44 isoforms was studied in paraffin material of 61 clinical Wilms tumors. Patients were treated preoperatively with chemotherapy and mean followup was 5.7 years. RESULTS: Generally CD44s, CD44v5 and CD44v10 were expressed in normal kidney tissues and at variable levels in the 3 cell types of Wilms tumor (blastemal, epithelial and stromal). No CD44v6 expression was found neither in normal kidney or in tumor tissue. CD44s, CD44v5 and CD44v10 epithelial expression gradually decreased from stage T1 to T3. By contrast the percentage of CD44 positive cells in the blastemal component significantly increased from T1 to T3. CD44 immunoreactive blastema cells were found in 62%, 44% and 41% for CD44s, CD44v5 and CD44v10, respectively. Blastemal expression of CD44s and CD44v5 statistically significantly correlated with clinicopathological stage. Univariate and multivariate analyses showed that blastemal CD44v5 expression was indicative of poor prognosis. CONCLUSIONS: Increased expression of CD44v5 in the blastemal part of Wilms tumor correlated with tumor stage, clinical progression and tumor related death. Therefore, blastemal CD44v5 expression may be of value in identifying patients with a high propensity for distant metastases. These patients might benefit from adjuvant chemotherapy and/or radiotherapy.  相似文献   
66.
The distribution of epithelial membrane antigen (EMA) in the kidney and its tumours has been studied using a polyclonal anti-EMA antiserum and the immunoperoxidase-antiperoxidase technique (PAP). Twelve fetal and 10 adult kidneys examined showed EMA to be confined to the distal tubular or collecting duct epithelium or their embryological precursors. The examination of 55 primary renal tumours showed EMA to be present on the epithelial tumours, on tubular epithelium in nephroblastoma, but not on mesenchymal tumour cells nor on undifferentiated areas of nephroblastoma.  相似文献   
67.
A 4-year-old child presenting with sudden- onset paraplegia and a sacral tumour in association with spina bifida occulta is reported. There were no stigmata of spinal dysraphism at birth. Imaging studies confirmed a sacral tumour with extradural extension up to T10 and spinal dysraphism. The histological features of the extradural and sacral components of the tumour were consistent with a Wilms tumour. The differential diagnosis included a primary sacral teratoma containing Wilms tumour elements or a primary extrarenal Wilms tumour arising in association with a spinal dysraphism. There was no clinical response to chemotherapy or radiotherapy. Received: 31 August 1999 / Accepted: 10 December 1999  相似文献   
68.
NOV蛋白在切割海马伞大鼠海马中表达的变化   总被引:2,自引:0,他引:2  
通过切割右侧海马伞制备大鼠海马伞损伤模型,应用Westernblotting、免疫组织化学技术,观察切割海马伞后不同时程海马中肾母细胞瘤过度表达基因(NOV)蛋白表达的变化,并对结果进行图像处理和统计学分析。Westernblotting结果显示,NOV蛋白在切割海马伞后3d表达开始上升,14d达高峰后缓慢下降。切割海马伞后14d切割侧和正常侧相比较,海马CA1-CA3区的锥体细胞层及齿状回颗粒层NOV阳性细胞数目无显著性差异(P>0.05),但切割侧NOV阳性细胞明显比正常侧深染,两侧比较平均灰度值有显著性差异(P<0.01)。结合本课题组以往的工作,本研究结果提示,切割海马伞后海马中高表达的NOV蛋白可能参与了诱导神经干细胞迁移和向神经元分化的过程。  相似文献   
69.
Wilms' tumour (nephroblastoma) has been associated with chromosomal abnormalities at the 11p13, 11p15 and 16q regions. A study into the possibility of mutations occurring within p53, the ubiquitous adult tumour suppressor gene, in Wilms' tumour was carried out. Thirty-eight ca ses were studied. Of these 36 were categorised into the favourable histology group and two into the unfavourable histology group based on the National Wilms' Tumour Study criteria. Archival formalin-fixed, paraffin-embedded tissue sections from each case were stained with a polyclonal (AB565:Chemicon) and a monoclonal (DO7:Dako) antibody raised against p53 protein using a peroxidase-labelled streptavidin biotin kit (Dako). 'Cure' (disease-free survival of 60 months or longer) was documente d in 39% of cases with favourable histology tumours. Eleven percent in this group succumbed to the disease. Both cases with unfavourable histology died. Four out of 36 (11%) tumours with favourable histology demonstrated weak to moderate staining with both AB565 and DO7 in more than 75% of tumour cells. In contrast, p53 protein expression in unfavourable histology tumours was significantly increased compared with the favourable histology group ( P  = 0.021) with both cases demons trating immunopositivity in >75% of tumour cells when stained with AB565 and DO7. The intensity of staining ranged from moderate to strong in both cases. It appears from this preliminary study that the immunohistochemical expression of p53 protein in Wilms' tumour, presumably a result of mutation in the p53 tumour suppressor gene, correlates with histological classification, histological categorisation being one of the useful features in the prognostic assessment of Wilms' tumours.  相似文献   
70.
目的:对26例散发性肾母细胞瘤的p53基因缺失进行检测,并分析其与组织类型的关系.方法:采用Southern印迹分子杂交技术.结果:1例p53等位基因缺失为间变型肾母细胞瘤.结论:p53基因缺失可能与间变型肾母细胞瘤的发生有关.  相似文献   
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