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781.
Objective. The goal of this article is to analyze the relationship between religion, measured in terms of religious affiliation and religiosity, and public opinion about same‐sex marriage, civil unions, and a federal constitutional amendment that would prohibit gay marriage. Methods. We use logistic regression with calculated standardized coefficients to analyze data from a nationally representative survey of 1,610 respondents conducted in March–April 2004. Results. Religious variables perform better than demographic measures in models of attitudes about same‐sex unions. Non‐Protestants are much more likely to support same‐sex unions than are Protestants, and individuals with conservative attitudes toward morality and secularism and (to a lesser extent) those who participate actively in religious life are more likely to oppose such unions. On the whole, religious variables play a weaker role in predicting support for a constitutional amendment to prevent gay marriage than they do in predicting attitudes toward same‐sex unions. Conclusions. Religious variables play powerful roles in structuring attitudes about same‐sex unions. Moreover, homosexuality appears to be a major component of the “moral values” discourse that is currently so popular in American politics.  相似文献   
782.
783.
The research ethics review process is now an inherent part of conducting research and a topic of much discussion. On the negative side it has been presented as cumbersome, expensive, time consuming, and potentially a system that does not adequately deal with the concerns it was set up to address. One common, but often controversial, proposal to address some of these concerns has been the institutionalization of centralized systems of review. This paper uses data on the review systems in place in five countries (Australia, Canada, New Zealand, the USA and the U.K.), some with and some without versions of centralized review, to explore issues related to centralization of the review process. It suggests that there are at least three types of systems (fully centralized, dual, and decentralized or multicommittee) in place; all are made up of two, interrelated components (the administrative and ethics review). We suggest that both components need to be considered in discussions about centralized review. Serious consideration of centralization of the administrative component may address many concerns. Centralization of the ethics review may provide a context that deals with other issues and may encourage reviews that more effectively focus on the ethical issues involved.  相似文献   
784.
There is considerable debate surrounding the choice of methods to estimate information fraction for futility monitoring in a randomized non-inferiority maximum duration trial. This question was motivated by a pediatric oncology study that aimed to establish non-inferiority for two primary outcomes. While non-inferiority was determined for one outcome, the futility monitoring of the other outcome failed to stop the trial early, despite accumulating evidence of inferiority. For a one-sided trial design for which the intervention is inferior to the standard therapy, futility monitoring should provide the opportunity to terminate the trial early. Our research focuses on the Total Control Only (TCO) method, which is defined as a ratio of observed events to total events exclusively within the standard treatment regimen. We investigate its properties in stopping a trial early in favor of inferiority. Simulation results comparing the TCO method with alternative methods, one based on the assumption of an inferior treatment effect (TH0), and the other based on a specified hypothesis of a non-inferior treatment effect (THA), were provided under various pediatric oncology trial design settings. The TCO method is the only method that provides unbiased information fraction estimates regardless of the hypothesis assumptions and exhibits a good power and a comparable type I error rate at each interim analysis compared to other methods. Although none of the methods is uniformly superior on all criteria, the TCO method possesses favorable characteristics, making it a compelling choice for estimating the information fraction when the aim is to reduce cancer treatment-related adverse outcomes.  相似文献   
785.
Historically early phase oncology drug development programmes have been based on the belief that “more is better”. Furthermore, rule-based study designs such as the “3 + 3” design are still often used to identify the MTD. Phillips and Clark argue that newer Bayesian model-assisted designs such as the BOIN design should become the go to designs for statisticians for MTD finding. This short communication goes one stage further and argues that Bayesian model-assisted designs such as the BOIN12 which balances risk-benefit should be included as one of the go to designs for early phase oncology trials, depending on the study objectives. Identifying the optimal biological dose for future research for many modern targeted drugs, immunotherapies, cell therapies and vaccine therapies can save significant time and resources.  相似文献   
786.
Root cause analysis can be used in foodborne illness outbreak investigations to determine the underlying causes of an outbreak and to help identify actions that could be taken to prevent future outbreaks. We developed a new tool, the Quantitative Risk Assessment-Epidemic Curve Prediction Model (QRA-EC), to assist with these goals and applied it to a case study to investigate and illustrate the utility of leveraging quantitative risk assessment to provide unique insights for foodborne illness outbreak root cause analysis. We used a 2019 Salmonella outbreak linked to melons as a case study to demonstrate the utility of this model (Centers for Disease Control and Prevention [CDC], 2019). The model was used to evaluate the impact of various root cause hypotheses (representing different contamination sources and food safety system failures in the melon supply chain) on the predicted number and timeline of illnesses. The predicted number of illnesses varied by contamination source and was strongly impacted by the prevalence and level of Salmonella contamination on the surface/inside of whole melons and inside contamination niches on equipment surfaces. The timeline of illnesses was most strongly impacted by equipment sanitation efficacy for contamination niches. Evaluations of a wide range of scenarios representing various potential root causes enabled us to identify which hypotheses, were likely to result in an outbreak of similar size and illness timeline to the 2019 Salmonella melon outbreak. The QRA-EC framework can be adapted to accommodate any food–pathogen pairs to provide insights for foodborne outbreak investigations.  相似文献   
787.
This paper characterizes empirically achievable limits for time series econometric modeling and forecasting. The approach involves the concept of minimal information loss in time series regression and the paper shows how to derive bounds that delimit the proximity of empirical measures to the true probability measure (the DGP) in models that are of econometric interest. The approach utilizes joint probability measures over the combined space of parameters and observables and the results apply for models with stationary, integrated, and cointegrated data. A theorem due to Rissanen is extended so that it applies directly to probabilities about the relative likelihood (rather than averages), a new way of proving results of the Rissanen type is demonstrated, and the Rissanen theory is extended to nonstationary time series with unit roots, near unit roots, and cointegration of unknown order. The corresponding bound for the minimal information loss in empirical work is shown not to be a constant, in general, but to be proportional to the logarithm of the determinant of the (possibility stochastic) Fisher–information matrix. In fact, the bound that determines proximity to the DGP is generally path dependent, and it depends specifically on the type as well as the number of regressors. For practical purposes, the proximity bound has the asymptotic form (K/2)log n, where K is a new dimensionality factor that depends on the nature of the data as well as the number of parameters in the model. When ‘good’ model selection principles are employed in modeling time series data, we are able to show that our proximity bound quantifies empirical limits even in situations where the models may be incorrectly specified. One of the main implications of the new result is that time trends are more costly than stochastic trends, which are more costly in turn than stationary regressors in achieving proximity to the true density. Thus, in a very real sense and quantifiable manner, the DGP is more elusive when there is nonstationarity in the data. The implications for prediction are explored and a second proximity theorem is given, which provides a bound that measures how close feasible predictors can come to the optimal predictor. Again, the bound has the asymptotic form (K/2)log n, showing that forecasting trends is fundamentally more difficult than forecasting stationary time series, even when the correct form of the model for the trends is known.  相似文献   
788.
Substance use during the perinatal period and while parenting can pose a significant risk to children's safety and well-being. Mothers who have experienced child maltreatment are more likely to use substances than mothers without a history of maltreatment. This study explores how child welfare social workers experience supporting young, maltreated mothers struggling with substance use to prevent the intergenerational transmission of child maltreatment. Semi-structured in-depth interviews were conducted with four social workers working with young mothers with a history of maltreatment and substance use. Interpretative Phenomenological Analysis revealed two themes: (1) grappling with system challenges and (2) supporting strategies for disrupting intergenerational transmission of child maltreatment. The results highlight the need for systemic changes around support for social workers who work with young mothers who use substances and have a history of maltreatment, and substance use treatment and mental health programs themselves. Mothers need access to prenatal programs that are trauma-informed, non-judgemental and that support participants' basic needs and parenting skills.  相似文献   
789.
Evidence indicates that being overly dependent on the teacher places children's academic and socioemotional development at risk. However, little is known about what predicts dependency on the teacher or how the quality of interactions occurring within the classroom peer system may impact how children relate to their teacher the following school year. The current study tested the proposition that peer victimization may result in negative perceptions of classmates (i.e., peer beliefs), leading to overreliance on teachers. Data were collected from 365 children in the fall and spring of their third/fourth grade year and the fall of their fourth/fifth grade year (195 girls; Mage = 8.92 years; 86.8% white). Peer-reports of peer victimization and self-reports of peer beliefs were collected at each wave of the study. Teacher-reports of dependency were collected in the fall of the first and second years of the study. Path analyses showed that for boys peer victimization directly predicted higher levels of dependency on the next year's teacher, and, for boys and girls, peer victimization indirectly predicted dependency through lower levels of prosocial peer beliefs. Supplemental analyses assessing teacher-child conflict and closeness confirmed that findings were unique to dependency. These results underscore how children's perceptions of their classmates may contribute to dependency in their relationships with teachers and highlight the need for further research into the transactional and cumulative impact of difficulties within peer and teacher relationships.  相似文献   
790.
Studies investigating services for families experiencing complex and multiple problems have emphasized the need for more child-centred support. The aim of this longitudinal study was to investigate whether providing child-centred services (Child and Youth Coaching) combined with family-focused services (Ten for the Future) is effective for children growing up in families experiencing complex and multiple problems. Children's psychosocial skills, emotional and behavioural problems, and the quality of their pedagogical environment were measured at baseline, 6 months and 12 months. Parent and coach reports of children indicated for Child and Youth Coaching (n = 57) and nonindicated children (n = 18) were analysed using repeated measures multilevel models. Both parents and coaches reported improved psychosocial skills of children, but changes were only significant for coach reports. In both reports, no significant decrease in emotional and behavioural problems was observed for both indicated and nonindicated children. Many children still experienced considerable problems at case closure. Furthermore, no significant improvement in quality of the pedagogical environment was observed in both groups. Given the limitations in this study, more research is needed to identify whether these findings can be replicated and attributed to the Child and Youth Coaching and Ten for the Future programmes.  相似文献   
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