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81.
Excess of DR3/4 in type I diabetes. What does it portend? 总被引:1,自引:0,他引:1
The HLA-DR genotypes of 158 new type I diabetic probands from simplex families are compared with those of 43 multiply affected sibships. There were no significant differences in the gene frequencies of the insulin-dependent diabetes mellitus (IDDM)-associated alleles, DR3 and DR4, and whereas the DR3/4 heterozygotes were as frequent among simplex probands as among the first affected of multiplex sibships, subsequently affected sibs displayed lower frequencies of this genotype in this as well as in previously reported samples, indicating that the excessive risk associated with DR3/4 heterozygosity depends on the order of affection and thus on environmental factors. It is proposed that the penetrance of the susceptibility gene is enhanced by epistatic effects of this genotype and that this enhancement is strongest under conditions of low environmental liability. Thus, the excessive risk for DR3/4 individuals appears to depend on secondary interactions between DR and the environmental factors that trigger the onset of this disease and does not in itself indicate the existence of distinct susceptibility alleles in coupling with these genes, i.e., of genetic heterogeneity or overdominance. 相似文献
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A scoring system for identification of men at high risk of a heart attack within 5 years of screening is presented. The full scoring system includes an electrocardiogram and blood cholesterol measurement and the top fifth of the distribution of this full score yields 59% of the major ischaemic heart disease events occurring in the 5 years after screening. An intermediate scoring system, without an electrocardiogram but retaining blood cholesterol, yields 58% of cases from the top fifth of the score distribution. A basic (GP) score, without electrocardiogram or blood cholesterol measurement, yields 54% of cases and is recommended for use in opportunistic screening in general practice. This high risk strategy would increase public awareness of the size of the problem, help to prevent premature death and provide a useful complement to the population strategies of health education and government policy. 相似文献
85.
Renal disease and syphilis: a report of nephrotic syndrome with minimal change disease 总被引:3,自引:0,他引:3
N K Krane P Espenan P D Walker S M Bergman J D Wallin 《American journal of kidney diseases》1987,9(2):176-179
A case of nephrotic syndrome and acute renal failure in a 74-year-old man with latent syphilis is described. A renal biopsy demonstrated focal global sclerosis in three of nine glomeruli, however, the remaining glomeruli revealed typical lesions of minimal change disease. Previous reports of renal involvement in syphilis have described membranous glomerulonephritis, mesangial and endothelial cell proliferative glomerulonephritis, and, recently, rapidly progressive glomerulonephritis. The proteinuria and renal failure resolved after penicillin therapy alone. This response strongly suggested that there was a causal relationship between the syphilis and the nephrotic syndrome. This is the first report of such a relationship. 相似文献
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Dithiocarbamate-induced biliary platinum excretion and the control of cis-platinum nephrotoxicity 总被引:1,自引:0,他引:1
M A Basinger M M Jones S G Gilbreath E M Walker E P Fody M A Mayhue 《Toxicology and applied pharmacology》1989,97(2):279-288
Treatment with any one of six different dithiocarbamates subsequent to the administration of cis-platinum (CDDP) is shown to promote the biliary excretion of platinum. The administration of the most effective of these compounds, sodium diethyldithiocarbamate (DDTC) at 1.57 mmol/kg, led to a 30-fold increase in the biliary excretion of platinum. For the other dithiocarbamates investigated, a similar dosage led to increases ranging from approximately 5-fold for sodium iminodiacetic acid dithiocarbamate, to 26-fold for sodium sarcosine dithiocarbamate. The presence of alkyl groups on the nitrogen of the dithiocarbamate increased the effectiveness of the compounds. There is no increase in the platinum levels of the brain when DDTC is used in this manner. A histopathological evaluation of the kidneys of rats given 15 mg CDDP/kg in 6.3% saline with and without the use of dithiocarbamates for renal protection shows significant additional protection due to the use of the dithiocarbamates. Dithiocarbamates given at an appropriate dosing schedule can lead to a significant reduction in the renal damage which is revealed by microphotographs. It is suggested that part of the renal protection obtained by the use of dithiocarbamates may be due to this shift of platinum excretion to the bile which obviates additional renal exposure to platinum. It was also found that the simultaneous injection of a dithiocarbamate with the cis-platinum has no obvious effect on the anti-cancer action of cis-platinum against the Walker 256 carcinosarcoma in rats. 相似文献
88.
Digital radiography of subtle pulmonary abnormalities: an ROC study of the effect of pixel size on observer performance 总被引:3,自引:0,他引:3
Forty conventional radiographs with examples of mild interstitial infiltrates and subtle pneumothoraces and 40 normal studies of the chest were selected and digitized, with pixel sizes of 1.0, 0.5, 0.2, and 0.1 mm. Observer performance tests were carried out using receiver operating characteristic analysis. Conventional radiographs and digitized images were compared. The results indicate that, in such cases, diagnostic accuracy increases significantly as the pixel size is reduced, at least to the 0.1-mm level. We conclude that, for digital systems using screen-film or similar image receptors, use of a pixel size substantially larger than 0.1 mm may result in some loss of diagnostic accuracy. 相似文献
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