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排序方式: 共有1059条查询结果,搜索用时 15 毫秒
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Arent S; Mallat M; Westendorp R; van der Woude F; van Es L 《Nephrology, dialysis, transplantation》1997,12(8):1672-1679
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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导数光谱系数倍率法测定多组分体系感冒清胶囊中盐酸吗啉胍的含量 总被引:1,自引:0,他引:1
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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Application of reflectance spectroscopy to the estimation of uric acid, urea and glucose: an evaluation of the Ames Seralyzer 下载免费PDF全文
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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The Role of APO-1-Mediated Apoptosis in the Immune System 总被引:12,自引:0,他引:12
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