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Approximately 10% of patients with superficial bladder cancer (pTa/pT1) recur with life-threatening muscle-invasive disease. Identification of these patients has been a major goal of bladder cancer research. In 1994, it was suggested that p53 immunostaining could identify the cancers that would progress and it was proposed that tumours that stain for p53 should be treated aggressively with radiotherapy or cystectomy. Despite the hundreds of studies published since on the relationship between p53 and progression in superficial bladder cancer, the clinical utility of p53 immunostaining has not been resolved because of limitations concerning the numbers of patients and the length of follow-up. This study set out to overcome these limitations by using tissue from a large multicentre trial that recruited 502 patients with a median follow-up of 10 years. Each of 34 patients that had progressed with >/= pT2 disease or had distant metastases or had died from bladder cancer was compared with one or two matched controls. Sections were stained with a mouse monoclonal antibody to p53, pAb1801. In agreement with many of the earlier studies, p53 immunostaining had prognostic significance. The adjusted hazard ratio for time to progression for the pAb1801-positive versus negative group was 2.5, with 95% confidence intervals of 1.05-5.98 (p = 0.039). The other major risk factor that is associated with progression of superficial bladder cancer is pT1G3 disease. Of the 42 pT1G3 cancers, 14 (33%) progressed. The proportion of cancers with p53 staining that progressed was similar to the proportion of pT1G3 cancers that progressed, but neither the sensitivity nor the specificity of association of p53 staining with progression is sufficient to recommend cystectomy in individual patients.  相似文献   
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A case of double aneuploidy involving chromosome 21 and Y is reported in an eight-month-old infant with developmental delay and failure to thrive. Patient had all classical phenotypical features of trisomy 21 except, absence of epicanthal folds. The diagnosis was confirmed by cytogenetic study performed on peripheral blood leucocyte culture using G-banding. Literature review revealed only 17 cases of XYY and trisomy 21 reported so far. No such case is reported in Indian literature. Relevant literature is reviewed and possible effects of trisomy 21 on XYY and that of XYY on trisomy 21 has been discussed. A routine chromosomal study even in patient with classical features of Down syndrome has been advocated. Interestingly, our patient also had left to right shunts at atrial and ductal level and tricuspid regurgitation. Given the rarity of the disorder and scanty published data the incidence, phenotype and recurrence risk are difficult to establish.  相似文献   
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Benign familial neonatal convulsions   总被引:2,自引:0,他引:2  
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Hemimegalencephaly is a rare cerebral malformation characterized by asymmetry of the hemispheres and cortical dysplasias. We report clinical and imaging findings in a child with hemimegalencephaly involving the right cerebral hemisphere with associated manifestations of tuberous sclerosis complex. Gross abnormal myelination pattern and gyral abnormalities were seen in the enlarged hemisphere. Subsequent scans showed atrophy of the frontoparietal region in the enlarged hemisphere and normal growth of the opposite hemisphere exceeding the size of the abnormal hemisphere in the frontoparietal region. A few white-matter lesions that were seen in the normal hemisphere on neonatal scan were difficult to appreciate on subsequent MR studies. The white-matter lesions were better seen in the neonatal period, whereas cortical tubers were better detected at a later age.  相似文献   
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BACKGROUND: Adjuvant chemotherapy has been suggested as a possible strategy to improve survival in women with early-stage ovarian cancer; however, all randomized studies to date have been too small to answer this question reliably. METHODS: We performed a preplanned combined analysis of two parallel randomized clinical trials (International Collaborative Ovarian Neoplasm 1 [ICON1] and Adjuvant ChemoTherapy In Ovarian Neoplasm [ACTION]) in early-stage ovarian cancer that compared platinum-based adjuvant chemotherapy with observation following surgery. Between November 1990 and January 2000, 925 patients (477 in ICON1 and 448 in ACTION) who had surgery for early-stage ovarian cancer were randomly assigned to receive platinum-based adjuvant chemotherapy (n = 465) or observation (n = 460) until chemotherapy was indicated. Kaplan-Meier analysis was used to compare overall and recurrence-free survival by treatment allocation. In subgroup analyses of pretreatment age, tumor stage, histologic cell type, and differentiation grade, the differences in relative size of effect were tested using a chi-square test for interaction or a chi-square test for trend. All tests of statistical significance were two-sided. RESULTS: After a median follow-up of over 4 years, 245 patients had died or had a recurrence (ICON1: 133, ACTION: 112). Overall survival at 5 years was 82% in the chemotherapy arm and 74% in the observation arm (difference = 8% [95% confidence interval (CI) = 2% to 12%]; hazard ratio [HR] = 0.67, 95% CI = 0.50 to 0.90; P =.008). Recurrence-free survival at 5 years was also better in the adjuvant chemotherapy arm than it was in the observation arm (76% versus 65%, difference = 11% [95% CI = 5% to 16%]; HR = 0.64, 95% CI = 0.50 to 0.82; P =.001). Subgroup analyses provided no evidence of a difference in the size of effect of chemotherapy on survival in any pretreatment subcategory. CONCLUSIONS: Platinum-based adjuvant chemotherapy improved overall survival and recurrence-free survival at 5 years in this combined group of patients with early-stage ovarian cancer defined by the inclusion criteria of the ICON1 and ACTION trials.  相似文献   
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