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A M Ibrahim Y M Shaker M F el-Hawary K I Fayek M M Zahran N K el-Shawarby 《Clinical physiology and biochemistry》1985,3(1):16-22
Total serum protein levels in 70 patients with urolithiasis were not significantly different from those in 20 control subjects, although certain variations were detected in individual protein patterns. In contrast, total urinary protein was significantly higher in patients with urolithiasis. 4-6 different components, i.e., albumin, alpha 1-acidic glycoprotein, alpha 1-antitrypsin, Gc-globulin, fibrinogen and immunoglobulin G, were found in the matrices of calculi and in urine, suggesting that proteinuria may play a role in the formation of stones in patients with urolithiasis. 相似文献
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The frequency and characteristics of highly thermophilic bacteria in cool soil environments 总被引:4,自引:0,他引:4
Following enrichment at 70 degrees C and 80 degrees C, five highly thermophilic aerobic eubacteria have been isolated from cool soil environments. These organisms show a temperature range for growth of 40-80 degrees C and have optimal and very high growth rates around 70 degrees C with generation times less than 30 min. All isolates are narrow rods, which stain Gram-negative, but have a Gram-positive cell wall structure and only one of five isolates is a spore former. All cultures contain a small proportion of previously unreported extremely long flexuous rods, which can be seen to divide eventually. Biochemical testing of five strains reveals a significant ability to utilize alkanes and some aromatic hydrocarbons. Using polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) of 16S rDNA the five strains were differentiated into three categories, which paralleled the biochemical results. 16S rDNA sequences showed high similarity with thermophilic Bacillus species now reclassified as Geobacillus. These bacteria are present in high numbers in apparently all soils and the question is raised of how these organisms, which are apparently unable to grow at the temperatures experienced in these cool soils, are so prominent. 相似文献
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Control of virulence by the two-component system CiaR/H is mediated via HtrA, a major virulence factor of Streptococcus pneumoniae 下载免费PDF全文
The CiaR/H two-component system is involved in regulating virulence and competence in Streptococcus pneumoniae. The system is known to regulate many genes, including that for high-temperature requirement A (HtrA). This gene has been implicated in the ability of the pneumococcus to colonize the nasopharynx of infant rats. We reported previously that deletion of the gene for HtrA made the pneumococcal strains much less virulent in mouse models, less able to grow at higher temperatures, and more sensitive to oxidative stress. In this report, we show that the growth phenotype as well as sensitivity to oxidative stress of Delta ciaR mutant was very similar to that of a Delta htrA mutant and that the expression of the HtrA protein was reduced in a ciaR-null mutant. Both the in vitro phenotype and the reduced virulence of Delta ciaR mutant could be restored by increasing the expression of HtrA. 相似文献
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Ibrahim MM de Angelis R Lima AS Viana de Carvalho GD Ibrahim FM Malki LT de Paula Bichuete M de Paula Martins W Rocha EM 《PloS one》2012,7(3):e33775
Purpose
Fungi are a major cause of keratitis, although few medications are licensed for their treatment. The aim of this study is to observe the variation in commercialisation of antifungal eye drops, and to predict the seasonal distribution of fungal keratitis in Brazil.Methods
Data from a retrospective study of antifungal eye drops sales from the only pharmaceutical ophthalmologic laboratory, authorized to dispense them in Brazil (Opthalmos) were gathered. These data were correlated with geographic and seasonal distribution of fungal keratitis in Brazil between July 2002 and June 2008.Results
A total of 26,087 antifungal eye drop units were sold, with a mean of 2.3 per patient. There was significant variation in antifungal sales during the year (p<0.01). A linear regression model displayed a significant association between reduced relative humidity and antifungal drug sales (R2 = 0.17,p<0.01).Conclusions
Antifungal eye drops sales suggest that there is a seasonal distribution of fungal keratitis. A possible interpretation is that the third quarter of the year (a period when the climate is drier), when agricultural activity is more intense in Brazil, suggests a correlation with a higher incidence of fungal keratitis. A similar model could be applied to other diseases, that are managed with unique, or few, and monitorable medications to predict epidemiological aspects. 相似文献67.
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We consider a class of semiparametric models for the covariate distribution and missing data mechanism for missing covariate and/or response data for general classes of regression models including generalized linear models and generalized linear mixed models. Ignorable and nonignorable missing covariate and/or response data are considered. The proposed semiparametric model can be viewed as a sensitivity analysis for model misspecification of the missing covariate distribution and/or missing data mechanism. The semiparametric model consists of a generalized additive model (GAM) for the covariate distribution and/or missing data mechanism. Penalized regression splines are used to express the GAMs as a generalized linear mixed effects model, in which the variance of the corresponding random effects provides an intuitive index for choosing between the semiparametric and parametric model. Maximum likelihood estimates are then obtained via the EM algorithm. Simulations are given to demonstrate the methodology, and a real data set from a melanoma cancer clinical trial is analyzed using the proposed methods. 相似文献