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1.
Aging is one of the contributing risk factors for kidney diseases. Accumulating evidence prompts the view that telomere length in kidney tissue cells is an indicator for organismal aging. Previously identified aging markers (cathelin-related antimicrobial peptide (CRAMP), stathmin, elongation factor-1α (EF-1α), and chitinase) were associated not only with telomere driven aging in mice but also with human aging and chronic diseases. This study focuses on the relationship between these biomarkers and IgA nephropathy (IgAN) progression in the Chinese population. For 260 individuals, the four markers are determined in blind datasets using direct enzyme-linked immunosorbent assay (ELISA) and immunofluorescence staining. The expression levels of CRAMP and chitinase increased in blood plasma, urine, and kidney tissues during human IgAN progression. And for the other nephropathy, such as systemic lupus erythematosus (SLE), diabetic nephropathy (DN), and focal segmental glomerulosclerosis (FSGS), there is no protein upregulation with telomere shortening. Moreover, a combination of CRAMP and chitinase can distinguish patients with IgAN from healthy individuals with 88.2%/92.5% (plasma) and 74.3%/84.2% (urine) sensitivity/specificity. These data provide the experimental evidence that telomere shortening and related inflammatory proteins are associated with human IgAN, and it could be a new direction for the disease progression study.  相似文献   

2.
为分析系统性红斑狼疮(systemic lupus erythematous,SLE)误诊一例,就病人肺部渗出性炎症改变中潜藏的毛玻璃样改变的特征,采用小剂量激素予以诊断性治疗,并进行排除诊断.误诊的原因主要是:本例属系统性红斑狼疮对肺部侵犯,导致肺间质性改变,一般容易误诊为炎症、感染,甚则肺水肿.而结合现代影像学诊断,尤其是利用HRCT薄层扫描.能给肺部间质性改变的诊断提供重要的诊断依据.  相似文献   

3.
用ELISA法建立了检测IgM、IgG、IgA三种类风湿因子。在类风湿关节炎(RA)中IgM-RF,IgG-RF,IgA-RF的阳性率分别为67.1%,58.6%,42.8%,明显高于其他结缔组织病,且OD值也高。ELISA法检测IgM-RF的阳性率明显高于乳胶凝集法检测的阳性率,但特异性一样为2.3%,但弥补了乳胶凝集法只能检测IgM-RF的不足,尤其是建立了IgG-RF和IgA-RF的检测,对临床诊断有很大帮助,我们还发现IgA-RF和SS有一定关系。  相似文献   

4.
5.
Thirty-nine meta-analyses obtained from the past 10 years of communication research (1997–2007) were reanalyzed using fixed effects (FE), random effects (RE), and Hunter and Schmidt (HS) meta-analytic methods. The majority of studies (62%) reported use of the HS model in the original analysis. Differences identified between models include (a) greater propensity for Type 1 error under the FE approach, (b) episodes of inflated effect size (ES) under the RE approach, and (c) high levels of heterogeneity in population ESs across studies. Recommendations are made for scholars to appropriately choose and implement meta-analytic models in future research.  相似文献   

6.
The present article considers a fundamental question in evaluation research: “By how much do program effects vary across sites?” The article first presents a theoretical model of cross-site impact variation and a related estimation model with a random treatment coefficient and fixed site-specific intercepts. This approach eliminates several biases that can arise from unbalanced sample designs for multisite randomized trials. The article then describes how the approach operates, explores its assumptions, and applies the approach to data from three large welfare-to-work trials. The article also illustrates how to report cross-site impact findings and presents diagnostics for assessing these findings. To keep the article manageable, it focuses on experimental estimates of effects of program assignment (effects of intent to treat), although the ideas presented can be extended to analyses of multisite quasi-experiments and experimental estimates of effects of program participation (complier average causal effects).  相似文献   

7.

Objectives

Low-density granulocytes (LDGs) can form neutrophil extracellular traps (NETs) spontaneously and excessively. When peripheral blood mononuclear cells (PBMCs) are used for studying T lymphocytes, LDGs contained in the PBMCs may decrease the threshold of activating T lymphocytes by forming NETs. This study focused on the profiles of LDGs in common autoimmune diseases and methods for removing LDGs from PBMCs.

Methods

The percentages of LDGs in PBMCs from 55 patients with dermatomyositis (DM), 15 with polymyositis (PM), 42 with rheumatoid arthritis (RA), 25 with systemic lupus erythematosus (SLE), and 19 healthy controls were determined by flow cytometry. Three methods of removing LDGs were explored and compared. After removal, PBMCs from six patients with positive T-SPOT.TB were tested again to find out if LDGs contained in the PBMCs could influence T lymphocyte reactions.

Results

Significantly higher LDG percentages were found in PBMCs from patients with DM ((8.41±10.87)%, P<0.0001), PM ((8.41±10.39)%, P<0.0001), RA ((4.05±6.97)%, P=0.0249), and SLE ((7.53±11.52)%, P=0.0006), compared with the controls ((1.28±0.73)%). The T-SPOT.TB values significantly decreased after LDGs were removed. Increasing relative centrifugal force (RCF) within a limited range can decrease the LDG percentage from an initial high level, but not markedly increase the LDG clearance rate. Compared with the whole blood sediment method, the PBMC adherence method can significantly remove LDGs yet scarcely influence the T lymphocyte percentage in PBMCs.

Conclusion

The LDG percentage in PBMCs is significantly increased in patients with SLE, DM, PM, and RA. The influence of LDGs on T lymphocytes cannot be ignored in PBMC cultures. The adherence method is a simple and easy-to-use method for removing LDGs and purifying T lymphocytes from PBMCs.
  相似文献   

8.
There is overwhelming evidence that hypertension is an important risk factor for both macrovascular and microvascular complications in patients with diabetes, but the problem remains to identify appropriate goals for preventive therapies. A number of guidelines (the European Society of Cardiology (ESC)/European Association for the Study of Diabetes (EASD) 2007, the Joint National Committee (JNC)-VII 2003, the American Diabetes Association (ADA) 2011) have for example advocated a blood pressure goal of less than 130/80 mmHg, but this suggestion has been challenged by findings in recent trials and meta-analyses (2011). The European Society of Hypertension (ESH) therefore recommends a systolic blood pressure goal of “well below” 140 mmHg. Based on evidence from both randomized controlled trials (hypertension optimal treatment (HOT), action in diabetes and vascular disease: preterax and diamicron MR controlled evaluation (ADVANCE), action to control cardiovascular risk in diabetes (ACCORD)) and observational studies (ongoing telmisartan alone and in combination with ramipril global endpoint trial (ONTARGET), international verapamil-trandolapril study (INVEST), treat to new targets (TNT), and the National Diabetes Register (NDR)), it has been shown that the benefit for stroke reduction remains even at lower achieved blood pressure levels, but the risk of coronary events may be uninfluenced or even increased at lower systolic blood pressure levels. In a recent meta-analysis, it was therefore concluded that the new recommended goal should be 130–135 mmHg systolic blood pressure for most patients with type 2 diabetes. Other risk factors should also be controlled with a more ambitious strategy applied in the younger patients with shorter diabetes duration, but a more cautious approach in the elderly and frail patients with a number of vascular or non-vascular co-morbidities. In patients from East Asia, such as China, the stroke risk is relatively higher than the risk of coronary events. This must also be taken into consideration for individualized goal setting in relation to total risk, for example in patients from stroke-prone families. In conclusion, the current strategy is to have a more individualized approach to risk factor control in patients with type 2 diabetes, also relevant for blood pressure control.  相似文献   

9.
The question of whether students’ school-year learning rates differ by race/ethnicity is important for monitoring educational inequality. Researchers applying different modeling strategies to the same data (the ECLS-K:99) have reached contrasting conclusions on this question. We outline the similarities and differences across three common approaches to estimating gains and heterogeneity in gains: 1) a gain score model (with intercept), 2) a first-difference (FD) model (in some cases equivalent to regression-through-the-origin [RTO] and student fixed effects models), and 3) a student random effects (RE) model. We show via simulation that FD/RTO and RE models produce estimates of learning rates – and group differences in learning rates – with more favorable RMSD compared to the gain score model with intercept. Using data from the ECLS-K:99, we demonstrate that these precision differences lead to contrasting inferences regarding learning rate heterogeneity, and likely explain the inconsistencies across previous studies.  相似文献   

10.
Preschool teachers' job stressors have received increasing attention but have been understudied in the literature. We investigated the impacts of a classroom-based intervention, the Chicago School Readiness Project (CSRP), on teachers' perceived job stressors and confidence, as indexed by their perceptions of job control, job resources, job demands, and confidence in behavior management. Using a clustered randomized controlled trial (RCT) design, the CSRP provided multifaceted services to the treatment group, including teacher training and mental health consultation, which were accompanied by stress-reduction services and workshops. Overall, 90 teachers in 35 classrooms at 18 Head Start sites participated in the study. After adjusting for teacher and classroom factors and site fixed effects, we found that the CSRP had significant effects on the improvement of teachers' perceived job control and work-related resources. We also found that the CSRP decreased teachers' confidence in behavior management and had no statistically significant effects on job demands. Overall, we did not find significant moderation effects of teacher race/ethnicity, education, teaching experience, or teacher type. The implications for research and policy are discussed.  相似文献   

11.
Objective: XRCC1 polymorphism is a research hotpot in individual treatment for non-small cell lung cancer (NSCLC). To obtain the association between XRCC1 polymorphism and clinical outcome of platinum-based treatment for NSCLC, a meta-analysis was conducted. Methods: Databases including PubMed, Embase, Cochrane, and Chinese National Knowledge Infrastructure (CNKI) were searched for publications that met the inclusion criteria. A fixed effect model was used to estimate pooled odds ratio (OR) and hazard ratio (HR) with 95% confidence interval (CI) for the association between XRCC1 Arg399Gln and response or survival of platinum-based treatment for advanced NSCLC. A chi-squared-based Q-test was used to test the heterogeneity hypothesis. Egger’s test was used to check publication bias. Results: Seventeen published case-control studies that focus on the association between XRCC1 Arg399Gln and response or survival of platinum-based treatment for advanced NSCLC in 2 256 subjects were included in this meta-analysis, of whom 522 were AA genotypes (23.2% frequency), 916 AG genotypes (40.6% frequency), and 818 GG genotypes (36.2% frequency). The overall response rate (ORR) was 45.2% (110/243) for AA genotype patients, 29.9% for AG genotype (73/244), and 30.7% for GG genotype (124/403). The heterogeneity test did not show any heterogeneity and the Egger’s test did not reveal an obvious publication bias among the included studies. The meta-analysis indicated that AA genotype patients presented higher response rates toward platinum drug treatment compared with G model (GG+GA) patients (GG vs. AA model: OR=0.489, 95% CI 0.266–0.900, P=0.021; AG vs. AA model: OR=0.608, 95% CI 0.392–0.941, P=0.026; GA+AA vs. GG model: OR=1.259, 95% CI 0.931–1.701, P=0.135; GG+GA vs. AA model: OR=0.455, 95% CI 0.313–0.663, P=0.0001). However, no evidence validates XRCC1 associates with the survival following platinum drug therapy. Conclusions: Our meta-analysis suggested that XRCC1 Arg399Gln is related with the sensitivity of NSCLC patients to platinum-based treatment. AA genotype patients present more desirable curative effectiveness compared with other patients.  相似文献   

12.
This study evaluated a positive parenting program to Brazilian mothers who used corporal punishment with their children. The intervention was conducted in four agencies serving vulnerable children, and at a home replica laboratory at the University. Mothers who admitted using corporal punishment were randomly assigned between experimental (n = 20) and control group (n = 20). The program consisted of 12 individual sessions using one unit from Projeto Parceria (Partnership Project), with specific guidelines and materials on positive parenting, followed by observational sessions of mother-child interaction with live coaching and a video feedback session in the lab. The study used an equivalent group experimental design with pre/post-test and follow-up, in randomized controlled trials. Measures involved: Initial Interview; Strengths and Difficulties Questionnaire (SDQ) – parent and child versions; Beck Depression Inventory (BDI); observational sessions with a protocol; and a Program Evaluation by participants. Analysis of mixed models for repeated measures revealed significant positive effects on the BDI and SDQ total scores, as well as less Conduct problems and Hyperactivity in SDQ measures from the experimental group mothers, comparing pre with post-test. Observational data also indicated significant improvement in positive interaction from the experimental group mothers at post-test, in comparison with controls. No significant results were found, however, in children’s observational measures. Limitations of the study involved using a restricted sample, among others. Implications for future research are suggested.  相似文献   

13.
本文是第一篇探索斯坦福成就阅读考试(第十版)的原本及其客户化版本的结构相似性的文章。研究分析是跨年级在多个观测变量(个别题目,题组,题包)上进行的。分析方法主要包括线性和非线性的探索性和实证性因素分析。分析结果表明在所有文章内的试题,都有不同程度的题组效应。在所有的模型当中,个别题目作为观测变量的模型的拟合度最低,题组作为观测变量的模型的拟合;其次,题包作为观测变量的模型的拟合度最高。在三种结构等性等级:同性等性(congenric),陶性等性(tau-equivalent)和并行等性(parallel)中,斯坦福成就阅读考试原本与其客户化版本的结构具有同性相似。  相似文献   

14.
Preschool teachers’ job stressors have received increasing attention but have been understudied in the literature. We investigated the impacts of a classroom-based intervention, the Chicago School Readiness Project (CSRP), on teachers’ perceived job stressors and confidence, as indexed by their perceptions of job control, job resources, job demands, and confidence in behavior management. Using a clustered randomized controlled trial (RCT) design, the CSRP provided multifaceted services to the treatment group, including teacher training and mental health consultation, which were accompanied by stress-reduction services and workshops. Overall, 90 teachers in 35 classrooms at 18 Head Start sites participated in the study. After adjusting for teacher and classroom factors and site fixed effects, we found that the CSRP had significant effects on the improvement of teachers’ perceived job control and work-related resources. We also found that the CSRP decreased teachers’ confidence in behavior management and had no statistically significant effects on job demands. Overall, we did not find significant moderation effects of teacher race/ethnicity, education, teaching experience, or teacher type. The implications for research and policy are discussed.  相似文献   

15.
Test administrators are appropriately concerned about the potential for time constraints to impact the validity of score interpretations; psychometric efforts to evaluate the impact of speededness date back more than half a century. The widespread move to computerized test delivery has led to the development of new approaches to evaluating how examinees use testing time and to new metrics designed to provide evidence about the extent to which time limits impact performance. Much of the existing research is based on these types of observational metrics; relatively few studies use randomized experiments to evaluate the impact time limits on scores. Of those studies that do report on randomized experiments, none directly compare the experimental results to evidence from observational metrics to evaluate the extent to which these metrics are able to sensitively identify conditions in which time constraints actually impact scores. The present study provides such evidence based on data from a medical licensing examination. The results indicate that these observational metrics are useful but provide an imprecise evaluation of the impact of time constraints on test performance.  相似文献   

16.
In this paper, we investigate the effects of a community- and school-based service learning experience (SLE) on pre-service physical education teachers’ Indigenous knowledge, cultural competency and pedagogy. Informed by the theoretical tenets of Indigenous research methodologies, experiential learning and critical reflection, we examine 55 final-year pre-service physical education teachers’ (age: 21.9 [8.3]; 10.7% low SES; 68% females) cultural learning and competency in a core unit of study with a six-week SLE. Measures of their experiences included reflective journals, multicultural teaching competency scales and focus group interviews. Findings support the design of the SLE, with statistically significant changes in pre-service teachers’ perceptions of their cultural competency (p < 0.001). Pre-service teachers were able to challenge their assumptions about Indigenous students, plan and implement student-centred and culturally relevant pedagogies. Attention is drawn to the design of this SLE and demonstrates the importance of using Indigenous community members and teachers as mentors, which has not been explored in previous SLE studies.  相似文献   

17.
Because random assignment is not possible in observational studies, estimates of treatment effects might be biased due to selection on observable and unobservable variables. To strengthen causal inference in longitudinal observational studies of multiple treatments, we present 4 latent growth models for propensity score matched groups, and evaluate their performance with a Monte Carlo simulation study. We found that the 4 models performed similarly with respect to model fit, bias of parameter estimates, Type I error, and power to test the treatment effect. To demonstrate a multigroup latent growth model with dummy treatment indicators, we estimated the effect of students changing schools during elementary school years on their reading and mathematics achievement, using data from the Early Childhood Longitudinal Study Kindergarten Cohort.  相似文献   

18.
中国雷公藤制剂治疗系统性红斑狼疮疗效的Meta分析   总被引:1,自引:0,他引:1  
应用Cochrne协作网和保存系统评价的专用分析软件RevMan4.2进行Meta分析,对1982年至今我国公开发表的运用雷公藤制剂辅助或联合其他药物治疗系统性红斑狼疮的文献进行临床疗效的综合评价分析.结果表明,符合并纳入该次Meta分析的文献共有九篇,经卡方检验OR=0.26(95%CI为0.16~0.40),OR值大于零,且"漏斗图"图形基本对称并偏向对照组,表明雷公藤制剂治疗系统性红斑狼疮有较为明显的效果.  相似文献   

19.
Testing a component model of reading comprehension in a randomized controlled trial, we evaluated the efficacy of 4 interventions that were designed to target components of language and metacognition that predict children’s reading comprehension: vocabulary, listening comprehension, comprehension of literate language, academic knowledge, and comprehension monitoring. Third- and 4th-graders with language skills falling below age expectations participated (N = 645). Overall, the component interventions were only somewhat effective in improving the targeted skills, compared to a business-as-usual control (g ranged from ?.14 to .33), and no main effects were significant after correcting for multiple comparisons. Effects did not generalize to other language skills or to students’ reading comprehension. Moreover, there were Child Characteristic × Treatment interaction effects. For example, the intervention designed to build sensorimotor mental representations was more effective for children with weaker vocabulary skills. Implications for component models of reading and interventions for children at risk of reading comprehension difficulties are discussed.  相似文献   

20.
This article summarizes results from 12 empirical evaluations of observational methods in education contexts. We look at the performance of three common covariate-types in observational studies where the outcome is a standardized reading or math test. They are: pretest measures, local geographic matching, and rich covariate sets with a strong theory of treatment selection. Overall, the review demonstrates that although the pretest often reduces bias in observational studies, it does not always eliminate it. Its performance depends on the pretest's correlation with treatment selection and the outcome, and whether preintervention trends are present. We also find that although local comparisons are prioritized for matching, its performance depends on whether comparable no-treatment cases are available. Otherwise, local comparisons may produce badly biased results. In cases where researchers have a strong theory of selection and rich covariate sets, observational methods perform well, but additional replication studies are needed. Finally, observational methods that rely on demographic covariates without a theory of selection rarely produce unbiased treatment effects. The article concludes by offering education researchers empirically based guidance on covariate selection in observational studies.  相似文献   

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