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排序方式: 共有220条查询结果,搜索用时 140 毫秒
81.
82.
Wai H. Lim Joshua R. Lewis Germaine Wong Robin M. Turner Ee M. Lim Peter L. Thompson Richard L. Prince 《PloS one》2014,9(9)
Background
Reduced estimated glomerular filtration rate (eGFR) using the cystatin-C derived equations might be a better predictor of cardiovascular disease (CVD) mortality compared with the creatinine-derived equations, but this association remains unclear in elderly individuals.Aim
The aims of this study were to compare the predictive values of the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI)-creatinine, CKD-EPI-cystatin C and CKD-EPI-creatinine-cystatin C eGFR equations for all-cause mortality and CVD events (hospitalizations±mortality).Methods
Prospective cohort study of 1165 elderly women aged>70 years. Associations between eGFR and outcomes were examined using Cox regression analysis. Test accuracy of eGFR equations for predicting outcomes was examined using Receiver Operating Characteristic (ROC) analysis and net reclassification improvement (NRI).Results
Risk of all-cause mortality for every incremental reduction in eGFR determined using CKD-EPI-creatinine, CKD-EPI-cystatin C and the CKD-EPI-creatinine-cystatic C equations was similar. Areas under the ROC curves of CKD-EPI-creatinine, CKD-EPI-cystatin C and CKD-EPI-creatinine-cystatin C equations for all-cause mortality were 0.604 (95%CI 0.561–0.647), 0.606 (95%CI 0.563–0.649; p = 0.963) and 0.606 (95%CI 0.563–0.649; p = 0.894) respectively. For all-cause mortality, there was no improvement in the reclassification of eGFR categories using the CKD-EPI-cystatin C (NRI -4.1%; p = 0.401) and CKD-EPI-creatinine-cystatin C (NRI -1.2%; p = 0.748) compared with CKD-EPI-creatinine equation. Similar findings were observed for CVD events.Conclusion
eGFR derived from CKD-EPI cystatin C and CKD-EPI creatinine-cystatin C equations did not improve the accuracy or predictive ability for clinical events compared to CKD-EPI-creatinine equation in this cohort of elderly women. 相似文献83.
84.
【目的】了解絮凝基因FLO1中重复DNA序列B和D对絮凝蛋白Flo1p功能的影响,为构建遗传稳定的最小絮凝功能基因奠定理论基础。【方法】通过PCR和融合PCR方法分别克隆到完整的絮凝基因FLO1、重复DNA序列B和D分别缺失的衍生基因FLO1b和FLO1d,分析这些基因在非絮凝酵母中表达对细胞絮凝特性的影响。【结果】与完整絮凝基因相比,重复DNA序列B和D分别缺失后对酵母细胞絮凝强度没有明显影响,但不同基因在酵母菌中表达产生的絮凝特性受环境因素,如甘露糖浓度和pH等的影响有明显差异。FLO1中重复DNA序列B和D缺失后,细胞絮凝特性受甘露糖抑制的敏感性降低;同时对环境pH的改变具有更广泛的适应性。【结论】重复DNA序列B和D对絮凝蛋白Flo1p结构和功能具有调控作用,二者缺失后,特别是D缺失后会使絮凝蛋白在极端酸碱环境下更稳定。 相似文献
85.
Teng E Leong KP Li HH Thong B Koh ET Loi PL Zhao Y Tan EK;TTSH RA Study Group 《DNA and cell biology》2012,31(4):607-610
A genome-wide association study in Japan identified the C-C chemokine receptor type 6 gene (CCR6) as associated with rheumatoid arthritis (RA). This finding has not been validated in other Asian populations. A case-control study involving 996 subjects, comprising 440 controls and 556 RA patients, was done to determine their anticyclic citrullinated peptide (anti-CCP) antibody status and CCR6 polymorphism (rs3093024) genotype. Three hundred eighty-seven patients were anti-CCP positive and 153 anti-CCP negative. Logistic regression showed that allele A was likely to increase the risk of developing RA among females via a recessive model (odds ratio [OR]=1.55, 95% confidence interval [CI]=1.01, 2.39), whereas the risk effect appeared to be reduced among males via an additive model (OR=0.60, 95% CI=0.42, 0.85). Considering only subjects who are anti-CCP positive, allele A increased RA risk among females via a recessive model (OR=1.68, 95% CI=1.07, 2.64) but decreased the risk among males via an additive model (OR=0.59, 95% CI=0.39, 0.89). We showed that CCR6 polymorphism was a risk factor among females but a protective factor among males. Functional studies are warranted to unravel the pathophysiological relevance of the gene variant and other linked variants with RA. 相似文献
86.
Regulation of insulin gene transcription 总被引:5,自引:0,他引:5
87.
88.
Over the last several years, there has been increasing interest in the role of proteins of the TIM (T cell immunoglobulin and mucin domain) family in regulating immune responses. Despite what the name suggests, proteins of this family function in a much more widespread manner than just on T cells, as we will discuss in this review. We therefore propose that the definition of TIM be adjusted to "transmembrane immunoglobulin and mucin". 相似文献
89.
Oxalate, a common constituent in many plants, is known to play important functional roles in plants. However, excess levels of oxalate in edible parts of plants adversely affect their quality as food. Understanding the regulatory mechanism in plants, particularly in food crops, is of both scientific and practical significance. While a number of studies have shown that nitrate can efficiently induce oxalate accumulation in plants, how it elicits such an effect is not well understood. This study aimed to gain a further insight into the mechanism underlying the nitrate-induced oxalate accumulation. Nitrate-N efficiently caused oxalate accumulation in rice leaves, depending on the nitrate concentrations and treatment time. In contrast, same nitrogen molar levels of the other N forms such as nitrite, ammonium, glutamate and urea either had no effect on the accumulation or even reduced the oxalate level. When glutamate, glutamine, asparate and asparagine were added into the nutrient solution that already contained saturating concentration of nitrate, both oxalate levels and NR activity were correspondingly decreased. In all of these modes of treatment, the change in NR activity was positively paralleled to that in oxalate levels. For a further confirmation, we generated the transgenic rice plants with a NR interference gene introduced. The result further demonstrated that in the transgenic plants, unlike in wild-type plants, oxalate was no longer able to accumulate in response to the nitrate treatment even though the endogenous nitrate levels were substantially elevated. Taken together, our results suggest that the nitrate-induced oxalate accumulation in rice leaves is dependent on the NR-catalyzed nitrate reduction, rather than on nitrate itself or nitrite reduction or its downstream metabolites. 相似文献
90.
Jiajia Wu Huaiqun Liu Peng Wang Dun Zhang Yan Sun Ee Li 《Indian journal of microbiology》2017,57(3):344-350
Sulfate-reducing bacteria (SRB) were found to be capable of tolerating a certain amount of oxygen (O2), but how they affect oxygen reduction reaction (ORR) has not been clear. The present work investigated the impact of SRB on ORR in 3.5 wt% sodium chloride solution with the cyclic voltammetry method. The addition of SRB culture solution hampered both the reduction of O2 to superoxide (O 2 ·? ) and hydrogen peroxide (H2O2) to water (H2O), and the influence of SRB metabolites was much larger than that of bacterial cells. Sulfide and extracellular polymeric substances (EPS), typical inorganic and organic metabolic products, had great impact on ORR. Sulfide played an important role in the decrease of cathodic current for H2O2 reduction due to its hydrolysis and chemical reaction activity with H2O2. EPS were sticky, easy to adsorb on the electrode surface and abundant in functional groups, which hindered the transformation of O2 into O 2 ·? and favored the reduction of H2O2 to H2O. 相似文献