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991.
Many children in the child welfare system (CWS) have histories of recurrent interpersonal trauma perpetrated by caregivers early in life often referred to as complex trauma. Children in the CWS also experience a diverse range of reactions across multiple areas of functioning that are associated with such exposure. Nevertheless, few CWSs routinely screen for trauma exposure and associated symptoms beyond an initial assessment of the precipitating event. This study examines trauma histories, including complex trauma exposure (physical abuse, sexual abuse, emotional abuse, neglect, domestic violence), posttraumatic stress, and behavioral and emotional problems of 2,251 youth (age 0 to 21; M = 9.5, SD = 4.3) in foster care who were referred to a National Child Traumatic Stress Network site for treatment. High prevalence rates of complex trauma exposure were observed: 70.4% of the sample reported at least two of the traumas that constitute complex trauma; 11.7% of the sample reported all 5 types. Compared to youth with other types of trauma, those with complex trauma histories had significantly higher rates of internalizing problems, posttraumatic stress, and clinical diagnoses, and differed on some demographic variables. Implications for child welfare practice and future research are discussed.  相似文献   
992.
The expression of externalizing behaviors of children in-care can be influenced by a multitude of factors. The current study examined the simultaneous levels of influence of workers and foster families on children's externalizing behaviors in those receiving out-of-home care. A cross-classified multilevel model was used to partition variance in children in-care's externalizing scores into worker, foster family and child-specific levels of influence. The extent to which processes are explained by worker and foster-family level predictors was examined. Assessment and Action Record (AAR) data from the Ontario Looking after Children (OnLAC) project were analyzed. The sample included data from 1063 children between 10 and 17 years of age (M age = 13 years, 6 months, SD = 2.08 years). While individual differences in children's externalizing behaviors were primarily attributable to child-specific effects (72%), 10% and 18% of the variance can be explained by worker and foster family influences respectively. Worker education accounted for substantial differences seen between workers where more difficult children were monitored by workers with less educational attainment. Furthermore, foster-family level predictors also explained variance in children's externalizing behaviors. Relative to children in foster care, those in kinship care displayed significantly lower levels of problem behaviors while children in group care displayed significantly higher levels. Higher levels of parental negativity within the foster family and the experience of more differential parental negativity relative to siblings were significantly associated with more externalizing behaviors. Lastly, children who were more satisfied with their placement displayed significantly lower levels of problematic behaviors. These results suggest that children in-care can be conceptualized within a multilevel framework.  相似文献   
993.
对脉冲式安培检测器与色谱联用技术的分离能力进行了简短的总结。那些过去置身于电流测定法研究中的学者们将会赞赏这些新方法。关于新方法的报道与日俱增,同时也正在开发有助于分离测定珍贵样品和标准品的微型系统。而这种方法应用之广应该引起所有分析化学家的注意。  相似文献   
994.
995.
‘Fixing the Economy’, shows how the modern understanding of ‘the economy’ as the totality of the relations of production, distribution and consumption of goods and services within a given country or region arose in a mid-twentieth-century crisis of economic representation. The economy, represented as an autonomous domain, participated in the (largely post-Second World War) re-imagining of the nation-state and the postcolonial international order, and provided a concept of development without political upheaval. In considering the economic life of an Egyptian village, however, Mitchell demonstrates that market and domestic production and consumption are irreducibly hybrid and that the practical foundations of the economy as representation make it impossible any longer to see its imagined referent as the very type of the non-discursive and the material.  相似文献   
996.
Methods for analysing unbalanced factorial designs can be traced back to the work of Frank Yates in the 1930s . Yet, still today the question on how his methods of fitting constants (Type II) and weighted squares of means (Type III) behave when negligible or insignificant interactions exist, is still unanswered. In this paper, by means of a simulation study, Type II and Type III ANOVA results are examined for all unbalanced structures originating from a 2x3 balanced factorial design within homogeneous groups (design types) accounting for structure, number of observations lost and which cells contained the missing observations. The two level factor is further analysed to test the null hypothesis, for both Type II and Type III analyses, that the unbalanced structures within each design type provide comparable F values. These results are summarised and the conclusion shows that this work agrees with statements made by Yates Burdick and Herr and Shaw and Mitchell-Olds, but there are some results which require further investigation.  相似文献   
997.
998.
From Aesop to Sun Tzu, the importance of working together has long been acknowledged. Yet as long as cooperation has existed, so have the difficulties associated with it. Pooling two fields might mean twice the power, but this union also brings twice the jargon, twice the competing theories, and twice the head butting. Nonetheless, in this collection, researchers have made a heroic effort to set aside their theoretical differences to produce three computational models for the influential set of empirical data showing that young infants have difficulty detecting correlations among features (Younger & Cohen, 1983, 1986). Specifically, Gureckis and Love (2004/this issue) fit a well‐developed adult‐learning model to the infant work (down to the exact order and number of test trials) in support of a common mechanism underlying categorization. Shultz and Cohen (2004/this issue) vary depth of processing in a cascade correlation network to show how older infants learn more than younger infants from the same amount of exposure. And Westermann and Mareschal (2004/this issue) introduce a model for their representational acuity hypothesis, which explains qualitative shifts as a decrease in the size of neural receptive fields. This commentary takes stock of this attempt at unifying computational modeling and developmental data by identifying common themes, clarifying points of disagreement, and providing a synthesis for this work.  相似文献   
999.
This paper investigates the linkages among demographic changes (fertility choice, marriage decision and mortality), real wages and real output in Greece over the period 1960–1998. The results show that in the long run a decrease in infant mortality rates, taking into consideration economic performance and the labor market, causes a reduction in fertility rates. In addition, the results suggest that an increase in real wages decreases nuptiality and fertility. Employing vector error-correction models and impulse response functions, the empirical results support the endogeneity of fertility choice to infant mortality, the labor market and the growth process.  相似文献   
1000.
In a closed population and defined time period, the mean number of opposite-sex partners reported by men and women should be equal. However, in all surveys, men report more partners. This inconsistency is pivotal to debate about the reliability of self-reported sexual behavior. We used data from the third National Survey of Sexual Attitudes and Lifestyles (Natsal-3), a probability sample survey of the British population, to investigate the extent to which survey sampling, accounting strategies (e.g., estimating versus counting), and (mis)reporting due to social norms might explain the inconsistency. Men reported a mean of 14.14 lifetime partners; women reported 7.12. The gender gap of 7.02 reduced to 5.47 after capping the lifetime partner number at the 99th percentile. In addition, adjusting for counting versus estimation reduced the gender gap to 3.24, and further adjusting for sexual attitudes narrowed it to 2.63. Together, these may account for almost two-thirds of the gender disparity. Sampling explanations (e.g., non-U.K.-resident partners included in counts; sex workers underrepresented) had modest effects. The findings underscore the need for survey methods that facilitate candid reporting and suggest that approaches to encourage counting rather than estimating may be helpful. This study is novel in interrogating a range of potential explanations within the same nationally representative data set.  相似文献   
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