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Bottomley  PA; Lee  Y; Weiss  RG 《Radiology》1997,204(2):403
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Patient survival after renal transplantation; more than 25 years follow-up   总被引:9,自引:2,他引:7  
Background: The determinators of patient survival after renal transplantation are incompletely known, and conflicting results hae been reported. This may have been influenced by time-related changes in patients selection, post-transplantation management and immunosuppressive regimens. This study was performed to evaluate in recipients of a first renal transplant the effect of patient characteristics, transplantation era, and the immunosuppressive regimen on patient survival. Method: We studied data from the Leiden Renal Transplant Database of all first renal transplantations performed between 1966 and 1994 in Leiden, the Netherlands. The effect of the following parameters on mortality was investigated: era of transplantation, sex, age at transplantation, cause of renal failure, immunosuppressive regimen, type and duration of pretransplantation dialysis, hypertension, diabetes mellitus, and smoking. In addition we analysed the causes of death. Results were expressed as crude mortality rates, relative risks of mortality, and standardized mortality ratios as compared with death rates in the Dutch population. Results: The analysis comprised 86 living donor transplant recipients and 916 cadaver transplant recipients. After adjustment for age and sex, the relative risk of morality for living donor transplant recipients compared with cadaver transplant recipients was 0.5 (95% CI 0.2 to 10.3, P=0.06). In the first cadaver kidney transplant recipients the risk of first-year mortality improved significantly with time, which coincided with the introduction of cyclosporin. The risk of mortality after the first year was higher in patients aged over 40 years at transplantation, men, smokers, and in the presence of hypertension or diabetes, but the effect of individual factors on mortality was small. We found no effect of the type of pretransplantation dialysis or the duration of pretransplantation haemodialysis on post-transplantation mortality. The standardized mortality ratio for recipients of first renal transplants was 14 times the population average in the first year after transplantation and was still four times in the remaining years. Conclusion: In the present study, time-related changes in patient management were responsible for improved patient survival in the first year after transplantation during the study period. Many individual factors contributed moderately to the risk of mortality after the first year. Compared to the general population the mortality rate of renal transplant recipients was significantly higher during the whole follow-up period.  相似文献   
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Prior studies have shown that pneumothorax is one of the more difficult entities to diagnose with digitized radiography. This study was designed to test whether increasing resolution from 1.25 to 2.5 line pairs per millimeter (lp/mm) and image processing (edge enhancement from unsharp masking) would increase accuracy and confidence in the diagnosis of pneumothorax, as well as normal cases and other forms of lung disease. Conventional radiographs were digitized with use of a laser reader and then reformatted as film hard copy. Eleven observers read 35 cases reformatted in three different ways (1.25 lp/mm, 2.5 lp/mm, 1.25 lp/mm unsharp mask). The images with finer resolution (2.5 lp/mm) and unsharp mask images were superior to those with coarser resolution (1.25 lp/mm) for the diagnosis of pneumothorax. There was no difference in diagnostic accuracy for normal patients. For abnormalities other than pneumothorax, the unsharp mask images were significantly worse. Confidence in the diagnosis of pneumothorax and other abnormalities was highest with the finest resolution (2.5 lp/mm).  相似文献   
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卢日刚 《药学学报》1992,27(11):871-874
This paper provides a basic principle and experimental technique of derivative signal multiplier spectrophotometry in multicomponent mixture. A microcomputer was used to process the spectral data measured on a manual spectrophotometer (UV-7520) for the determination of moroxydine hydrochloride in Gan Mao Qing capsules. Quantitative analysis of multicomponent mixture can be done without sample separation. The selection of optimal wavelength pairs is performed through the program with a computer. The method needs no special spectrophotometer and is simple, rapid and easy to operate. The mean recovery was 99.98 +/- 0.53% (n = 12).  相似文献   
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An original approach to the measurement of analytes in clinical chemistry has now become available, in which dry reagent strip technology is linked to measurement by reflectance spectroscopy. The present studies have evaluated the performance of the first of these test systems—for uric acid, urea and glucose, in serum—by comparison with conventional liquid chemistry methods. Satisfactory performance in terms of both precision and accuracy was obtained for all three test systems, the current “state-of-the-art” performance criteria being met; the Seralyzer system proved reliable and easy to use in the hands of trained operators. It should find a place as a “Stat” analyser in the laboratory, in specified wards and in Health Centres.  相似文献   
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