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1.
BackgroundClinical breast cancer subtypes are categorized basing on the expression of hormone receptors and overexpression of the human epidermal growth factor receptor 2 (HER2). It is still unclear whether parity impact the risk of different breast cancer subtypes.MethodsWe searched eight mainstream databases for published epidemiologic studies that assessed the relationship between parity and risk of breast cancer subtypes up to January 12, 2021. Parity number were unified into nulliparity and ever parity. The random-effects or fixed-effect models were used to calculate the pooled odds ratios (ORs) and 95% confidence intervals (CIs) among different subtypes. Restricted cubic spline analysis with four knots was applied to determine the relationship of parity number and risk of breast cancer subtypes.ResultsWe pooled sixteen case-control and four cohort studies, and performed an analysis including 7795 luminal A, 3576 luminal B, 1794 HER2-overexpressing, and 5192 triple-negative breast cancer cases among 1135131 participants. The combined ORs for ever parity versus nulliparity indicated a 34% reduction in luminal A risk (OR=0.66, 95% CI: 0.56–0.78), and a 29% reduction in luminal B risk (OR=0.71, 95% CI: 0.63–0.81), there was no significant association in HER2-overexpressing or TNBC risk. In the dose-response analysis, we observed a potentially non-linear and gradually increasing protective relationship between the number of parity and luminal breast cancer risk.ConclusionsThe effect of parity on breast cancer seems to vary among breast tumor subtypes, and it plays a protective role in luminal breast cancer.  相似文献   

2.
The Indian poultry industry is one of the fast-growing sectors of which duck farming plays an important role. Duck population in India is 33.51 million that is concentrated towards north-east and southern parts of the country who rears mainly for eggs and meat. Duck diseases are of great concern as they badly affect the financial status of the small, landless farmers. Databases such as Google Scholar, PubMed, J gate were used to search articles between 2000 and 2019 that showed the prevalence of viral, bacterial, and parasitic duck diseases. R open source software was used to derive forest plots by statistical analysis. Pooled prevalence estimates of duck diseases worldwide was found to be 20% (95%-CI:15–26). Also, continent-wise analysis of all duck diseases has revealed highest prevalence in North America, followed by Asia, Africa, Europe,Oceania and South America. This prevalence of data would be helpful to the policymakers to develop appropriate intervention strategies to prevent and control diseases in their respective locations.  相似文献   

3.
BackgroundBio-monitoring of polycyclic aromatic hydrocarbons (PAHs) contaminants in mother milk is essential to keep mothers and infants healthy against potential risks. The current study assesses the concentration of PAHs in mother milk through a meta-analytic and systematic review approach.MethodsAll the published studies up to December 2020 regarding the concentrations of various PAHs in mother milk were searched throughout major international databases such as PubMed, Scopus, and Web of Science. Moreover, the possible carcinogenic and mutagenic risks to infants were evaluated based on the BaP (benzo[a]pyrenee) equivalent dose.ResultsAccording to the results of 13 articles included among 936 retrieved studies, the lowest and highest concentration of PAHs was (0.125 ng/g) and (76.36 ng/g) related to benz(a)anthracenem and 1-methylnaphthalene, respectively. The highest (9.830 ng/g) and lowest (0.009 ng/g) concentration of PAHs was related to Mexico and Japan, respectively. Besides, carcinogenetic and mutagenic risk assessment of the PAHs indicated that risk pattern was different across countries. It can be concluded that the consumption of mother milk is safe and does not pose a risk due to the ingestion of PAHs to the health of infant consumers.  相似文献   

4.
The incorporation of local ecological knowledge in monitoring processes has been one of the great challenges of conservation initiatives worldwide. Therefore, it is essential to use indicators as local evaluation tools of the conditions of a species in order to support conservation actions. Local populations observe the environment, climate change and the influence of these factors on the species they use. However, their observations and perceptions may vary depending on different social factors. We used as model two species of economic importance involved in sociobiodiversity product chains to evaluate the role of social variables in the identification of conservation indicators for this plants. The species studied were: Caryocar coriaceum Wittm. (locally known as pequi), and Himatanthus drasticus (Mart.) Plumel (locally known as janaguba). We also registered which indicators are perceived as the most important and what they are measuring. Our results show that the knowledge among collectors is homogeneous and that, generally, the social factors do not affect the knowledge on local indicators. Age and extraction time were factors that influenced the knowledge on climate indicators and population structure only for C. coriaceum. In the communities studied, collectors not only monitor the biological characteristics of the species, but also the environmental and climatic phenomena that are threatening the sustainability of the species. These results can help to improve our ability to manage information about natural resources, incorporating local ecological knowledge in the scientific process of evaluation and monitoring of biodiversity.  相似文献   

5.
Cancer incidence is relatively low in sub-Saharan Africa (SSA), however, prognosis is expected to be poor in comparison with high-income countries. Comprehensive evidence is limited on the survival pattern of colorectal cancer patients in the region. We conducted a systematic review and meta-analysis to investigate the pattern of colorectal cancer survival in the region and to identify variation across countries and over time. We searched international databases MEDLINE, Scopus, Embase, Web of Science, ProQuest, CINAHL, and Google Scholar to retrieve studies that estimated survival from colorectal cancer in SSA countries from inception to December 31, 2021 without language restriction. Due to between-study heterogeneity, we performed a random-effects meta-analysis to pool survival rates. To identify study-level sources of variation, we performed subgroup analysis and meta-regression. Results are reported in line with the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) 2020 guideline and the protocol was registered in PROSPERO database (CRD42021246935). 23 studies involving 10,031 patients were included in the review, of which, 20 were included in the meta-analysis. The meta-analysis results showed that the pooled 1-, 2-, 3-, 4-, and 5-year survival rates in SSA were 0.74 (95% CI, 0.66–0.81), 0.50 (95% CI, 0.41–0.58), 0.36 (95% CI, 0.27–0.47), 0.31 (95% CI, 0.22–0.42), and 0.28 (95% CI, 0.19–0.38) respectively. Subgroup analyses indicated that the survival rate varied according to year of study, in which those conducted in recent decades showed relatively better survival. The 5-year survival was higher in middle-income SSA countries (0.31; 95%CI: 0.17–0.49) than low-income countries (0.20; 95%CI: 0.11–0.35), however, the difference was not statistically significant. In conclusion, survival from colorectal cancer is low in sub-Saharan Africa compared to other regions. Thus, intervention strategies to improve screening, early diagnosis and treatment of colorectal cancer should be developed and implemented to improve survival in the region.  相似文献   

6.
There is an on-going debate on the environmental effects of genetically modified crops to which this paper aims to contribute. First, data on environmental impacts of genetically modified (GM) and conventional crops are collected from peer-reviewed journals, and secondly an analysis is conducted in order to examine which crop type is less harmful for the environment. Published data on environmental impacts are measured using an array of indicators, and their analysis requires their normalisation and aggregation. Taking advantage of composite indicators literature, this paper builds composite indicators to measure the impact of GM and conventional crops in three dimensions: (1) non-target key species richness, (2) pesticide use, and (3) aggregated environmental impact. The comparison between the three composite indicators for both crop types allows us to establish not only a ranking to elucidate which crop is more convenient for the environment but the probability that one crop type outperforms the other from an environmental perspective. Results show that GM crops tend to cause lower environmental impacts than conventional crops for the analysed indicators.  相似文献   

7.
BackgroundThe relationship between silica and the risk of developing lung cancer has been established in previous literature, but how much the level of exposure to silica can increase the risk of lung cancer is a question that has been addressed in this review.MethodsThree electronic databases, including MEDLINE, Scopus, and Web of Science were searched for relevant literature. For the dose-response relationship between exposure to silica and developing lung cancer, we performed a meta-analysis using the random-effects model. For each level of exposure, we calculated the overall risk ratio (RR) with 95% confidence intervals (CI).ResultsNineteen studies were included in the meta-analysis. There was a positive and significant increasing dose-response trend between silica exposure and the risk of developing lung cancer as follows: < 0.50 mg/m3 1.14 (95% CI: 1.05, 1.23; I2 = 79%), 0.50–0.99 mg/m3 1.34 (95% CI: 1.05, 171; I2 = 45%), 1.00–1.99 mg/m3 1.14 (95% CI: 1.00, 1.30; I2 = 70%), 2.00–2.99 mg/m3 1.47 (95% CI: 1.05, 2.06; I2 = 57%), 3.00–3.99 mg/m3 1.44 (95% CI: 0.99, 2.11; I2 = 58%), and ≥ 4.00 mg/m3 1.64 (95% CI: 1.20, 2.24; I2 = 88%). The heterogeneity across studies was mild to moderate.ConclusionsThe presence of a dose-response relationship favors the causal relationship between exposure to silica and developing lung cancer.  相似文献   

8.
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   

9.
We introduce a measure of Environmental Consistency (ECo), which assesses the probability of reducing homogeneity in the environmental factors within a species’ distribution by randomly displacing its occurrences. ECo is computed by applying null model analysis to a species incidence matrix where each locality is associated with a set of environmental values. Environmental homogeneity is measured, for each species, as the average multiparametric distance between any pair of localities where the species occurs. ECo can account for the effect of species interactions and resource availability by using different null models that permit or forbid occurrence displacements altering species local abundance or species prevalence. ECo provides researchers with a flexible statistical framework to address a wide range of ecological and biogeographical issues. We investigated in depth the properties and the potentialities of ECo, showing how it integrates the concepts of Eltonian and Grinnelian niches. We demonstrate that a close relationship exists between niche breadth at species level and environmental consistency of species assemblages. In addition, we provide evidence that ecological consistency is closely related to species range. A software to compute ECo is freely available at http://forest.jrc.ec.europa.eu/download/software/eco.  相似文献   

10.
Although seagrass-based indicators are widely used to assess coastal ecosystem status, there is little universality in their application. Matching the plethora of available indicators to specific management objectives requires a detailed knowledge of their species-specific sensitivities and their response time to environmental stressors. We conducted an extensive survey of experimental studies to determine the sensitivity and response time of seagrass indicators to ecosystem degradation and recovery. We identified seagrass size and indicator type (i.e. level of biological organization of the measure) as the main factors affecting indicator sensitivity and response time to degradation and recovery. While structural and demographic parameters (e.g. shoot density, biomass) show a high and unspecific sensitivity, biochemical/physiological indicators present more stressor-specific responses and are the most sensitive detecting early phases of environmental improvement. Based on these results we present a simple decision tree to assist ecosystem managers to match adequate and reliable indicators to specific management goals.  相似文献   

11.
Currently there is a surge of interest in exploiting toxicogenomics to screen the toxicity of chemicals, enabling rapid and accurate categorisation into classes of defined mode-of-action (MOA), and prioritising chemicals for further testing. Direct infusion FT-ICR mass spectrometry-based metabolomics can provide a sensitive and unbiased analysis of metabolites in only 15 mins and therefore has considerable potential for chemical screening. The water flea, Daphnia magna, is an OECD test species and is utilised internationally for toxicity testing. However, no metabolomics studies of this species have been reported. Here we optimised and evaluated the effectiveness of FT-ICR mass spectrometry metabolomics for toxicity testing in D. magna. We confirmed that high-quality mass spectra can be recorded from as few as 30 neonates (<24 h old; 224 μg dry mass) or a single adult daphnid (301 μg dry mass). An OECD 24 h acute toxicity test was conducted with neonates at copper concentrations of 0, 5, 10, 25, 50 μg l−1. A total of 5447 unique peaks were detected reproducibly, of which 4768 were assigned at least one empirical formula and 1017 were putatively identified based upon accurate mass measurements. Significant copper-induced changes to the daphnid metabolome, consistent with the documented MOA of copper, were detected thereby validating the approach. In addition, N-acetylspermidine was putatively identified as a novel biomarker of copper toxicity. Collectively, our results highlight the excellent sensitivity, reproducibility and mass accuracy of FT-ICR mass spectrometry, and provide strong evidence for its applicability to high-throughput screening of chemical toxicity in D. magna. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

12.
Summary Plant species co-inhabiting a given geographical region often have distinetly different times of flowering. It is shown that such phenological spread, duc to short-term stochastic variation in weather variables, relaxes competition for empty sites to be colonized by diaspores. For sufficiently large spreads stable coexistence becomes possible. The applicability of the proposed hypothesis to the observed instances of phenological spread is discussed and shown to extend beyond that of other current theories.We thank L.-E. Liljelund, C. Solbreck and C. Wiklund for helpful comments. This work was carried out within the Swedish Coniferous Forest Project, supported by the Swedish Natural Science Research Council, the Swedish Environmental Protection Board, the Swedish Council of Forestry and Agricultural Research, and the Wallenberg foundation.  相似文献   

13.
An Environmental Assessment (EA) is one of the steps within the Environmental Impact Assessment process. Birds are often used in EA to help decision makers evaluate potential human impacts from proposed development activities. A “sensitivity to human disturbance” index, created by Parker III et al. (1996) for all Neotropical species, is commonly considered an ecological indicator. However, this parameter was created subjectively and, for most species, there have been no rigorous field test to validate its effectiveness as such. Therefore, in this study, we aim to: (1) evaluate if, at the local scale, birds from forest patches in a human-modified landscape (HML) may differ in sensitivity from Parker's sensitivity classification; (2) evaluate the effectiveness of the species richness value at each sensitivity level as an ecological indicator; (3) gather information on how often and in which manner Parker's classification has been used in EA. To do so, bird sampling was performed in eight forest patches in a HML over one year. Then, we created a local sensitivity to disturbance using information about threat, endemism, spatial distribution and relative abundance of all species in the study area. We found that 37% of the forest birds showed different local sensitivity levels when compared with Parker's classification. Our results show that only the richness of high-sensitivity species from our local classification fitted the ecological indicator assumptions helping the environmental conditions evaluation of the studied patches. We conclude that species richness of each Parker's bird sensitivity levels do not necessarily perform as an ecological indicator at the local scale, and particularly in HML. Nevertheless, Parker's Neotropical bird sensitivity classification was used in 50% of EA we reviewed. In these, 76% assumed that it was an accurate ecological indicator of the local forest conditions for birds. The lack of clear criteria used in Parker's classification allows diverse interpretations by ornithologists, and there is no agreement about the ecological meaning of each sensitivity level and what environmental conditions each level may indicate of. Therefore, the use of Parker's classification in EA may jeopardize accurate interpretations of proposed anthropogenic impacts. Furthermore, because a bird species’ sensitivity often varies between locations, we argue that Parker's generalized classification of bird sensitivity should not be used as an indicator of forest environmental conditions in EA throughout HMLs in Neotropics. Rather, local bird ecological indices should be explored, otherwise, erroneous predictions of the anthropogenic impacts will continue to be common.  相似文献   

14.
Saronikos Gulf, including the industrial zone of Elefsis Bay and the Port of Piraeus, is one of the most anthropogenically impacted coastal regions of Greece. Distinct assemblages of benthic foraminifers in sediment samples, collected from this gulf in February 2012, defined three zones that reflect abiotic parameters of the sediments (e.g., organic carbon, metal content). A low-diversity assemblage, dominated by stress-tolerant Ammonia tepida and Bulimina spp., was characteristic of samples from Elefsis Bay. Samples from the western and central part of Saronikos Gulf were the most variable with respect to both abiotic parameters and the foraminiferal assemblage, characterized by a mix of stress-tolerant and more sensitive taxa, especially Bolivina spp. and Nonion fabum. Samples from the coast of Salamis and at the eastern sector of the gulf were characterized by a diverse assemblage that included Peneroplis pertusus, miliolids, and a variety of small, epiphytic rotaliid taxa. A new biotic index, the Foram Stress Index (FSI), is based on the relative percentages of two ecological groups of benthic foraminiferal species, grouped according to their tolerance/sensitivity to organic matter enrichment and weighted proportionately to obtain a formula to define five ecological-status classes. The FSI produced three rankings for these samples (Poor, Moderate and Good), that strongly correlate with the macroinvertebrate-classification tool known as the BENTIX Index. The FSI provides a new tool to assess sediment or substrata quality based upon the benthic foraminiferal assemblages, which are a significant component of living meiobenthic communities that are generally not considered in most biotic benthic indices.  相似文献   

15.
Undertaking climate vulnerability assessments (CVAs) on marine fisheries is instrumental to the identification of regions, species, and stakeholders at risk of impacts from climate change, and the development of effective and targeted responses for fisheries adaptation. In this global literature review, we addressed three important questions to characterize fisheries CVAs: (i) what are the available approaches to develop CVAs in various social–ecological contexts, (ii) are different geographic scales and regions adequately represented, and (iii) how do diverse knowledge systems contribute to current understanding of vulnerability? As part of these general research efforts, we identified and characterized an inventory of frameworks and indicators that encompass a wide range of foci on ecological and socioeconomic dimensions of climate vulnerability on fisheries. Our analysis highlighted a large gap between countries with top research inputs and the most urgent adaptation needs. More research and resources are needed in low-income tropical countries to ensure existing inequities are not exacerbated. We also identified an uneven research focus across spatial scales and cautioned a possible scale mismatch between assessment and management needs. Drawing on this information, we catalog (1) a suite of research directions that could improve the utility and applicability of CVAs, particularly the examination of barriers and enabling conditions that influence the uptake of CVA results into management responses at multiple levels, (2) the lessons that have been learned from applications in data-limited regions, particularly the use of proxy indicators and knowledge co-production to overcome the problem of data deficiency, and (3) opportunities for wider applications, for example diversifying the use of vulnerability indicators in broader monitoring and management schemes. This information is used to provide a set of recommendations that could advance meaningful CVA practices for fisheries management and promote effective translation of climate vulnerability into adaptation actions.  相似文献   

16.
There is a growing understanding of the biophysical processes that regulate the stability of the Earth-system, yet human pressures on the planet continue to increase rapidly. Here, recent advances in defining Earth-system thresholds using the planetary boundaries framework are translated down to national and sub-national levels. A set of 10 indicators is developed in a biophysical accounting framework that links the sustainability of resource flows from the biosphere to final consumption. The indicator set includes three measures of physical stocks, three measures of aggregate resource consumption, and four indicators of sustainable scale. The four scale indicators are ratios of (i) cumulative carbon footprint relative to carbon budget, (ii) nutrient use relative to biogeochemical boundaries, (iii) blue water consumption relative to monthly basin-level availability, and (iv) land footprint relative to biocapacity. Taken together, the indicators measure how close high-consuming societies are to meeting the conditions of a “steady-state economy”, defined here as an economy with non-growing physical stocks and flows maintained within shares of planetary boundaries. The framework is applied over a 15-year period to the economies of Canada and Spain, along with two sub-national regions (Nova Scotia and Andalusia). Nova Scotia is the only study site experiencing stable or decreasing biophysical stocks and flows. None of the study sites are consuming resources within their shares of all four planetary boundaries. Overall, the set of indicators provides guidance for prioritizing which environmental pressures need to decline (and by how much) for societies to be more effective stewards of Earth-system stability.  相似文献   

17.
Bailer AJ  Piegorsch WW 《Biometrics》2000,56(2):327-336
As appreciation for human impact on the environment has developed, so have the experimental systems and associated statistical tools that quantify this impact. Toxicological study in particular has grown in its complexity and its need for advanced statistical support. Within this perspective, we describe statistical practice in environmental toxicology and risk assessment. We present two case studies, one from mammalian toxicology and one from aquatic toxicology, that highlight the evolution of statistical practice in environmental toxicology.  相似文献   

18.
Although generally considered environmentally friendly, wind power has been associated with extensive mortality of birds and bats. In this perspective, there is a need for reliable estimates of fatalities at wind farms, where the heterogeneity of the basic information, used among environmental assessment studies, is unlikely to support an accurate universal estimation method. We tested the applicability of the Stochastic Dynamic Methodology (StDM) to estimate bat fatalities, based on multifactorial cause–effect relationships (by integrating multi-model inference statistical analysis and dynamic modelling) between mortality estimates, detected fatalities and the selected key-components of the reality, such as the real number of bat mortalities simulated, the rate of carcasses removal, the searcher efficiency, the monitoring periodicity and the number of turbines for different realistic scenarios associated with particular wind farm conditions. Although some existing mortality estimators are considered accurate, the choice of a given universal formula for all mortality assessments, based on deterministic parameters and assumptions, may originate unsuspected errors. Therefore, we propose a flexible dynamic modelling framework, the StDM estimator, where the obtained algorithms are adaptable to the universe of application intended. The StDM estimator takes into account random, non-constant and scenario dependent parameters, providing bias-corrected estimates. The StDM estimator was applied for the European wind farm context and validated in the most cases tested, through the confrontation with independent data. Overall, this approach is considered a valuable tool to improve the quality of mortality estimates at onshore wind facilities, within the local, environmental and methodological gradients (including the cases where no mortality is detected), namely in the scope of environmental impact assessments and general ecological monitoring programmes.  相似文献   

19.
黄茄莉 《生态学报》2015,35(8):2712-2718
可持续发展水平的衡量是可持续发展研究的重要内容,它可以为政府的可持续发展决策提供重要的科学依据。现有的可持续性评价方法可分为指标列举法、流量分析法和系统分析法。前两类方法应用广泛,但理论基础较为薄弱,在指标的选取、标准化和赋权等方面存在一定的缺陷。基于系统运行机理的系统分析法尚不多见,但能弥补前两种方法的部分不足,Ulanowicz于2009年提出的演化模型是此类方法的代表。该模型从系统演化角度出发,以网络流为研究对象,以信息论为手段,指出系统的可持续性是系统上升性(效率)和恢复力平衡的结果,并提出了可持续性评价指标R。回顾了现有研究方法的优缺点。介绍了从演化视角分析可持续性的原理和数学模型,可持续发展的阈值范围以及该方法的应用案例。总结了该方法的应用步骤及尚需解决的问题。  相似文献   

20.
The growing public opposition to p-xylene (PX) project proposals in China requires understanding the divergence between the general public's risk perception and environmental risk assessment (ERA) results and its implications on its decision-making. In a case study in Fujian Province of China, a questionnaire was designed to investigate the public perception of risks of a proposed PX project, interviews were further conducted in Zhangzhou City and Xiamen City, and the survey results were compared with the ERA results of the proposed PX project. Results indicate that the environmental risk is acceptable according to current technical ERA guidelines and standards, while the public acceptance of the PX project is very low. The underlying factors causing the difference between the general public's risk perception and ERA results were identified from the ERA technical perspective. A better understanding of the risk perception divergence from different disciplinary perspectives is helpful for the public acceptance of these kinds of projects, which are on high demand in China. This study not only highlights the necessity to improve the risk communication but also provides insights on future research of ERA for this kind of large-scale project proposal.  相似文献   

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