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121.
This article presents additional follow-up analysis of women aged 45-49 from the Edinburgh Randomized Trial of Breast Cancer Screening. The screening protocol included four mammographic examinations at two-year intervals and seven annual clinical examinations. Altogether, 21,774 women aged 45-49 were recruited from 1978 to 1985 using cluster randomization. After 10-14 years of follow-up, breast cancer mortality has been reduced by 12% to 18% (rate ratios, with and without adjustment for socio-economic status, are 0.88 and 0.82 respectively, with 95% confidence intervals [CIs] of 0.55-1.41 and 0.51-1.32). These benefits are smaller than that reported previously with shorter follow-up. This article also presents data from an observational study that compared survival beyond baseline (50-52 years) of women first offered screening before and after age 50. Based on six-year data, the results suggest that earlier screening confers follow-up benefit (hazard ratio for later screening = 1.60; 95% CI: 0.96-2.67), but these findings are not statistically significant. The trial is too small to yield statistically significant results by itself, but can make useful contributions to overview and meta-analyses.  相似文献   
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The objective of this study was to evaluate the immune response and reactogenicity of a combined hepatitis B, diphtheria, tetanus and whole-cell Bordetella pertussis (DTPw-HBV) vaccine administered to healthy infants at 2, 4 and 6 months of age. A total of 179 infants (6-12 weeks of age) received three doses of DTPw-HBV vaccine. Blood samples for antibody determinations were taken before vaccination, 2 months after the second dose and 1 month after the third dose. Solicited and unsolicited symptoms were recorded by parents in a diary card. All vaccinees had protective levels of anti-HBs [geometric mean titre (GMT): 1526 mIU.ml-1], anti-diphtheria and anti-tetanus antibodies, 1 month after the third dose. Ninety-two percent of the subjects exhibited a response to the B. pertussis component. Most (99.4%) solicited reactions occurred within the first 48 h and the majority were mild or moderate. The safety, immunogenicity of this tetravalent vaccine was demonstrated when it was administered in infants following the 0, 2, 4-month dosing schedule.  相似文献   
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EDA is a facultative type III homology of human fibronectin encoded by an alternative spliced exon. The EDA+ and EDA- mRNA forms show a cell type specific distribution with their relative proportion varying during development, aging and oncogenic transformation. We have previously demonstrated that an 81 bp nucleotide sequence within the exon itself is essential for differential RNA processing. Fine mapping of cis acting elements within this region has been carried out to identify possible target sites for the modulation of alternative splicing. There are at least two short nucleotide sequences involved. Element A (GAAGAAGA) is a positive modulator for the recognition of the exon, its deletion results in constitutive exclusion of the EDA exon. Element B (CAAGG) is a negative modulator for exon recognition, its deletion results in constitutive inclusion of the EDA exon. This bipartite structure of the splicing enhancer is a novel feature of the mammalian exons.  相似文献   
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A model is proposed in which a neurovirulent, microglial-passaged, simian immunodeficiency virus (SIV) is used to produce central nervous system (CNS) pathology and behavioral deficits in rhesus monkeys reminiscent of those seen in humans infected with human immunodeficiency virus (HIV). The time course of disease progression was characterized by using functional measures of cognition and motor skill, as well as neurophysiologic monitoring. Concomitant assessment of immunological and virological parameters illustrated correspondence between impaired behavioral performance and viral pathogenesis. Convergent results were obtained from neuropathological findings indicative of significant CNS disease. In ongoing studies, this SIV model is being used to explore the behavioral sequelae of immunodeficiency virus infection, the viral and host factors leading to neurologic dysfunction, and to begin testing potential therapeutic agents.  相似文献   
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Two cases of treated plasma cell lesions of bone are reported for which contrast-enhanced MRI had suggested necrosis, based on lack of enhancement after gadolinium injection, and in which pathologic examinations revealed the presence of extensive viable neoplastic tissue. These cases highlight the need for cautious interpretation of contrast-enhanced MRI signs of response to treatment and inactivity of lesions in the setting of plasma cell neoplasms.  相似文献   
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BACKGROUND: The combination of 5-fluorouracil (5-FU) and cisplatin has shown great activity in many different types of tumour with an in vitro synergistic effect between 5-FU and cisplatin. A phase II study of 5-FU plus cisplatin was performed in 25 previously untreated patients with inoperable locally advanced or metastatic biliary tract carcinoma. PATIENTS AND METHODS: Twenty-five patients, 10 of them men and 15 women with a median age of 58, were entered into the study. The chemotherapy regimen consisted of 5-FU: 1 g/m2/day in continuous intravenous (i.v.) infusion for five consecutive days, and cisplatin: 100 mg/m2/day on day 2 in a one-hour infusion with standard hyperhydration. Twenty-two patients had metastatic tumours and three had locally advanced disease. RESULTS: Of the 25 patients entered into the study, 24 were evaluable for response and 25 for toxicity. Nausea and vomiting was the main toxic side effect in 19 patients. Severe, WHO grade 3-4 thrombocytopenia or neutropenia were observed in three and seven patients, respectively. There were no toxic deaths. Of 25 patients, six had partial remissions (overall response 24%, 95% confidence interval 7%-41%). For three patients, tumour reduction permitted local radiotherapy and one of these patients with initially advanced disease is still alive six years after the beginning of treatment. CONCLUSIONS: This study, one of the largest phase II trials performed in this disease, shows interesting activity of the combination of 5-FU and cisplatin in advanced biliary tract carcinoma.  相似文献   
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