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Summary This paper reports the 8-year results of comparing the use of two types of adjuvant chemotherapy following involved field radiotherapy for clinical stages I and II high-grade non-Hodgkin's lymphoma. Twenty-four patients received 6 weeks of VAP plus 2 years of oral maintenance chemotherapy, and 30 had six cycles of CMOPP. Four patients were not in complete remission at completion of i. v. chemotherapy (CR rate 91%). Ten patients (18.5%) have relapsed (VAP/M=5; CMOPP=5), with only two of these remaining alive, both of them being disease free. There have been three deaths from intercurrent causes, one from malignant melanoma and the other two from myocardial infarction. The relapse-free survivals at 2, 5 and 8 years were 80%, 76% & 76% respectively. The overall survivals at the same time points were 86%, 72% & 68%. There were no significant differences in either relapse-free or overall survival for either of the two treatment groups. The shorter period of weekly intravenous chemotherapy (VAP/M) was better tolerated than 36 weeks of CMOPP, and the former appears to produce equivalent results.  相似文献   
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1. The role of angiotensin as a modulator of proximal glomerulotubular (GT) balance was investigated in anaesthetized rats by examining the relationship between glomerular filtration rate (GFR) and absolute proximal reabsorption (APR) during removal of endogenous angiotensin II (AII) and III (AIII) with enalaprilat (CEI) and then during their subsequent replacement by intravenous infusions. 2. Enalaprilat lowered mean arterial blood pressure (MABP) and increased renal blood flow (RBF), GFR, urine flow rate and sodium excretion. Filtration fraction (FF) was not altered. Absolute proximal reabsorption, derived from fractional lithium clearance, increased by only 48% of the change expected for 'perfect' GT balance. 3. Angiotensin II replacement corrected MABP, GFR and plasma renin level, but reduced RBF and increased FF; APR was decreased and GT balance was restored. Urine flow and sodium excretion remained above control values with AII. 4. Replacement with AIII did not correct the hypotension but completely reversed the renal and renin responses to enalaprilat and restored GT balance without affecting FF. 5. It was concluded that the relation between proximal reabsorption and GFR is considerably modified by the intrarenal angiotensin concentration. The findings are best explained by a direct stimulation of proximal tubular sodium transport by angiotensin at the concentrations existing in anaesthetized rats.  相似文献   
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Research ethics committee audit: differences between committees.   总被引:2,自引:2,他引:0  
The same research proposal was submitted to 24 district health authority (DHA) research ethics committees in different parts of the country. The objective was to obtain permission for a multi-centre research project. The study of neonatal care in different types of unit (regional, subregional and district), required that four health authorities were approached in each of six widely separated health regions in England. Data were collected and compared concerning aspects of processing, including application forms, information required, timing and decision-making. The key finding was that ethics committees received and processed the applications variably, reflecting individual factors and local problems. To improve consensus and facilitate multicentre studies, standard forms and instructions are suggested and the establishment of a national committee or advisory group advocated.  相似文献   
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Attainment of a Class I molar relationship (Angle) is often a prime treatment objective. In addition to considerations of improved function and skeletodental harmonies, a Class I relationship often is deemed the "correct" and stable situation. This study assessed the relative stability of the sagittal molar relationship in orthodontically untreated persons with full dentitions who were followed longitudinally from young (approximately 20 years) to older (approximately 55 years) adulthood. The Class I relationship is indeed most stable; none of 69 cases (sides) starting in a Class I cusp-in-groove relationship moved from that condition. In contrast, Class II relationships naturally became significantly "more" Class II (that is, greater distoclusion), and Class III cases shifted significantly to greater mesioclusion.  相似文献   
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