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1.
There is still insufficient data about the risk-benefit profile about recommending non-aspirin, non-steroidal anti-inflammatory drugs (NA-NSAIDs) for colorectal cancer (CRC) prevention, especially in people aged 40 years or older. This study specifically addressed the association between regular NA-NSAIDs use and CRC risk in the population aged 40 years or older, performing a comprehensive systematic review and meta-analysis of all published studies on this topic until April 2018, by a search of PubMed, Scopus and Web of science databases and clinical trial registries. Two reviewers independently selected studies based on predefined inclusion criteria and assessed study quality using the Newcastle-Otawa scale. The data was combined with the random effects model. Potential heterogeneity was calculated as Q statistic and I2 value. A total of 23 studies involving more than 1 million subjects contributed to the analysis. Pooled odds ratio (OR) of NA-NSAIDs effects on CRC risk was 0.74 (0.67-0.81), I2 = 75.9%, p < 0.001. Heterogeneity was explained by a number of variables including the quality of the studies. Significant protective effects of NA-NSAIDs use were found for women (risk reduction of 19%), higher doses (risk reduction of 18%), distal colon cancer (risk reduction of 22%) and white people (risk reduction from 31% to 41%). From the results NA-NSAIDs use appears to be CRC chemopreventive for a specific subgroup of the population.  相似文献   
2.
To describe the effects of sodium-glucose co-transporter 2 (SGLT2) inhibitors on serum uric acid (SUA) in patients with type 2 diabetes mellitus (T2DM). PubMed, EMBASE, and CENTRAL were searched for randomized controlled trials of SGLT2 inhibitors in patients with T2DM up to Aug 10, 2017, without language or date restrictions. Thirty-one studies totaling 13,650 patients were included. SGLT2 inhibitors significantly decreased SUA levels compared with placebo, canagliflozin WMD –37.02?μmol/L, 95% CI [–38.41, –35.63], dapagliflozin WMD –38.05?μmol/L, 95% CI [–44.47, –31.62], empagliflozin WMD –42.07?μmol/L, 95% CI [–46.27, –37.86]. The drug class effect of SUA reduction suggesting SGLT2 inhibitors might be beneficial for diabetic patients with hyperuricemia.  相似文献   
3.
Falls in the hospital setting are a major health problem due to their high prevalence and their physical, functional, psychological or economic consequences. Since 1990s, different fall risk assessment scales have been developed to detect high-risk patients, which are also applied in the hospital setting. The aim of this review is to analyse the validity of different scales for assessing fall risk in adults in the hospital setting, especially in elderly patients. Following a literature search in April 2021, 36 primary studies were found that analysed the validity of the Downton, Morse, Hendrich II, Stratify and Tinetti scales. Meta-analyses of sensitivity and specificity showed a high heterogeneity that does not allow recommending a specific tool that can be considered as standard in acute inpatients.  相似文献   
4.
Backgroundsome recent studies have suggested that the risks of colon and rectal cancer increase with exposure to higher concentrations of nitrates in drinking water. This study is a meta-analysis of relevant studies.Methodsliterature published up to June 2021 was accessed and final results abstracted. Two cohort studies and seven case-control studies were analysed, and one case-control study not used because of limited data. Mixed effects meta-regression analysis was used to assess trends in colon cancer, rectal cancer, and colon cancer considered together, with nitrate concentrations in drinking water.ResultsThe usually accepted exposure upper limit for nitrates is 11.3 mg/l NO3-N. However most studies assess a lower range, with only one study providing data over 8 mg/l. Colorectal cancer risk increased by 2.4% (95% limits 0.4–4.5%) per unit increase in nitrate concentration, over a range from very low values to mid-range values. Extrapolation to higher dosages has insufficient data. The trend for rectal cancer is less than that for colon cancer.ConclusionThe increase in colorectal cancer risk with increasing nitrate concentration is lower than in some recent studies, and applies only over a small range. Extrapolation of these results to higher nitrate levels is not warranted. The studies vary greatly in their design, the nitrate concentrations assessed, and in their results. This association is weak and inconsistent, and may be influenced by bias and confounding factors. Any association of drinking water nitrates with colorectal cancer risk is small, and is uncertain.  相似文献   
5.
The aim of this meta-analysis was to determine the relationship between microRNA polymorphisms and the risk of childhood acute lymphoblastic leukemia comprehensively. PubMed, EMBASE, Scopus, Web of Science, the Cochrane Library, Global Index Medicus, Clinicaltrials.gov, ProQuest, and Open Grey databases were used to find relevant papers. Using the STATA 16.0 and CMA 3.0 software, the significance of relationships between microRNA polymorphisms and childhood acute lymphoblastic leukemia risk was evaluated using odds ratios (ORs) and 95 % confidence intervals (95 % CIs) for five genetic models. The results of the meta-analysis showed that there was no significant association between the polymorphism of miR-146a rs2910164 and childhood acute lymphoblastic leukemia risk in different genetic models. Also, in the sensitivity analysis, removing Xue's study from the analysis indicated that both the homozygote and recessive models are significantly affected. Additionally, there was a statistically significant relationship between the polymorphisms of pri-miR-34b/c rs4938723 (in the homozygote and recessive models) and miR-612 rs12803915 (in the allele and dominant models) and childhood acute lymphoblastic leukemia risk. These findings suggest that the rs4938723 and rs12803915 polymorphisms may have a role in the development of childhood acute lymphoblastic leukemia.  相似文献   
6.
BackgroundResults of the studies about association between serum selenium concentration and gestational hyperglycemia are inconsistent. Some studies have demonstrated that women with gestational diabetes mellitus (GDM) have lower Se concentrations while contrary results are reported in other studies.AimThe aim of this study is to compare the serum Se concentration in women with GDM and normoglycemic pregnant women via a systematic review and meta-analysis.MethodsA computerized literature search on four databases (PubMed, Cochrane register of control trials, Scopus and Google scholar) was performed from inception through August 2013. Necessary data were extracted and random effects model was used to conduct the meta-analysis.ResultsSix observational studies (containing 147 women with GDM and 360 normoglycemic pregnant women) were found, which had compared serum Se concentration in women suffering from GDM with normal pregnant ones. Our meta-analysis revealed that serum Se concentration was lower in women with GDM compared to normoglycemic pregnant women (Hedges = −1.34; 95% CI: −2.33 to −0.36; P < 0.01). Stratified meta-analysis demonstrated that concentration of Se in the sera of women with GDM was lower than normal pregnant women both in second and third trimesters, but the result was not significant in second trimester (second trimester: Hedges = −0.68; 95% CI: −1.60−0.25; P = 0.15, third trimester: Hedges = −2.81; 95% CI: −5.21 to −0.42; P < 0.05). It was also demonstrated that serum Se status was lower in pregnant women with impaired glucose tolerance (IGT) compared to normoglycemic pregnant women (Hedges = −0.85; 95% CI: −1.18 to −0.52).ConclusionThe available evidences suggest that serum Se concentration is significantly lower in pregnant women with gestational hyperglycemia compared to normal pregnant women.  相似文献   
7.
Pacific salmon (Oncorhynchus spp.) disturb sediments and fertilize streams with marine-derived nutrients during their annual spawning runs, leading researchers to classify these fish as ecosystem engineers and providers of resource subsidies. While these processes strongly influence the structure and function of salmon streams, the magnitude of salmon influence varies widely across studies. Here, we use meta-analysis to evaluate potential sources of variability among studies in stream ecosystem responses to salmon. Results obtained from 37 publications that collectively included 79 streams revealed positive, but highly inconsistent, overall effects of salmon on dissolved nutrients, sediment biofilm, macroinvertebrates, resident fish, and isotopic enrichment. Variation in these response variables was commonly influenced by salmon biomass, stream discharge, sediment size, and whether studies used artificial carcass treatments or observed a natural spawning run. Dissolved nutrients were positively related to salmon biomass per unit discharge, and the slope of the relationship for natural runs was five to ten times higher than for carcass additions. Mean effects on ammonium and phosphorus were also greater for natural runs than carcass additions, an effect attributable to excretion by live salmon. In contrast, we observed larger positive effects on benthic macroinvertebrates for carcass additions than for natural runs, likely because disturbance by live salmon was absent. Furthermore, benthic macroinvertebrates and biofilm associated with small sediments (<32 mm) displayed a negative response to salmon while those associated with large sediments (>32 mm) showed a positive response. This comprehensive analysis is the first to quantitatively identify environmental and methodological variables that influence the observed effects of salmon. Identifying sources of variation in salmon–stream interactions is a critical step toward understanding why engineering and subsidy effects vary so dramatically over space and time, and toward developing management strategies that will preserve the ecological integrity of salmon streams. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
8.
Denitrification in Aquatic Environments: A Cross-system Analysis   总被引:7,自引:0,他引:7  
A meta-analysis was conducted on 136 data sets of denitrification rates (DR) recorded both during the period of highest water temperature and monthly in five types of aquatic ecosystems: oceans, coastal environments, estuaries, lakes and rivers. There was a gradual increase of DR from the ocean to rivers and lakes at both scales, with the rivers showing the highest DR variability. Denitrification peaked during summertime and showed highest seasonal variability in lakes and rivers. High concentrations of nitrate and interstitially-dissolved organic carbon as well as low oxygen concentration in the overlying water enhanced DR both during summer and at a seasonal scale whereas total phosphorus did at the seasonal scale only. There was a positive linear relationship between overlying nitrate and DR over the range of 1–970 μmol NO3 (r 2 = 0.86, P = 0.001). DR in lakes and rivers might reach values doubling those in the more denitrifying terrestrial ecosystems (e.g. agrosystems). Discrepancies in DR and its controlling factors between site-specific studies and this meta-analysis may arise from environmental variability at two, often confounded, scales of observation: the habitat and the ecosystem level. Future studies on denitrification in aquatic environments should address the topic of spatial heterogeneity more thoroughly.  相似文献   
9.
目的:近年来,关于UCP2-866G/A基因多态性与肥胖关系的研究较多,但各研究的结果不尽一致.本文拟采用Meta分析的方法,对已公开发表的有关UCP2-866G/A基因多态性与肥胖的研究进行系统综合定量分析,以期科学的评价UCP2-866G/A基因多态性与肥胖的关系.方法:本研究运用计算机检索万方全文数据库、中国知网、维普数据库、中国生物医学文献数据库、PubMed等数据库收集关于UCP2-866G/A基因多态性与肥胖相关的公开发表的文献,选择OR值及其95%CI作为Meta分析指标.利用Stata10.0软件对各研究结果进行异质性检验和效应值合并计算.结果:根据统一的纳入和剔除标准,纳入14篇文献,共有肥胖者5195例,对照组9735人.在总人群中,UCP2-866G/A位点A/G的OR=0.931 (95%CI:0.884-0.980),AA+GA/GG的OR=0.924 (95%CI:0.859-0.994),AA/GG的OR=0.886 (95%CI:0.797-0.985),GA/GG的OR=0.925 (95%CI:0.856-0.999),有统计学意义.在欧洲人群中,UCP2-866G/A位点A/G的OR=0.912 (95%CI:0.857-0.970),AA+GA/GG的OR=0.882 (95%CI:0.808-0.962),AA/GG的OR=0.846 (95%CI:0.743-0.963),GA/GG的OR=0.893(95%CI:0.814-0.980),有统计学意义.但在亚洲人群中均无统计学意义.结论:我们认为-866G/A基因多态性与欧洲人群的肥胖有关,与亚洲人群的肥胖无关.  相似文献   
10.
Previous studies on the association between glycogen synthase kinase 3 beta (GSK3-β) polymorphisms (rs334558 and rs6438552) and Parkinson's disease (PD) susceptibility remained inconsistent. Thus, the goal of this study was to re-examine their exact association by a meta-analysis. All eligible studies were identified by a systematic literature search of multiple databases. Six studies (3105 cases and 4387 controls) on rs334558 and six studies (2579 cases and 4091 controls) on rs6438552 were included. The quality of these studies was generally good according to the Newcastle–Ottawa Scale (NOS). The meta-analysis showed null association between the two variants and PD susceptibility in all genetic models from the overall or Caucasian population. However, the analysis of rs334558 revealed that the risk of PD decreased in heterozygote, dominant or additive models (OR = 0.60, 95% CI: 0.48, 0.74; OR = 0.63, 95% CI: 0.51, 0.78; OR = 0.82, 95% CI: 0.71, 0.94, respectively) from the Eastern Asian population. Moreover, the analysis on the homozygote, heterozygote, dominant or additive models suggested that rs6438552 also reduced the PD risk (OR = 0.45, 95% CI: 0.24, 0.84; OR = 0.62, 95% CI: 0.39, 0.97; OR = 0.57, 95% CI: 0.37, 0.87; OR = 0.66, 95% CI: 0.49, 0.88, respectively) in the Eastern Asian population. Together, the findings suggest that the two variants both reduced the risk of PD in the Eastern Asian subgroup but not in the overall and Caucasian populations, which should be cautiously interpreted because of limited number of included studies.  相似文献   
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