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931.
The heterogeneity of the group of adopted children does not allow to draw general conclusions about the nature and quantity of behavioral problems with adopted children. This nature and quantity depend on the chosen comparison group. Older foreign adoptees at placement often show complex physical and psychological problems. Many suffer from some kind of behavioral disturbances. Empirical data show that reactive attachment disorder (RAD) can often be diagnosed. The continuation of this disorder in adulthood will result in feelings of psychic homelessness. Examples are described to make clear what kind of behavioral problem it concerns. Research to select appropriate treatments for RAD and psychic homelessness is still lacking.  相似文献   
932.
The Bayesian approach to inference stands out for naturally allowing borrowing information across heterogeneous populations, with different samples possibly sharing the same distribution. A popular Bayesian nonparametric model for clustering probability distributions is the nested Dirichlet process, which however has the drawback of grouping distributions in a single cluster when ties are observed across samples. With the goal of achieving a flexible and effective clustering method for both samples and observations, we investigate a nonparametric prior that arises as the composition of two different discrete random structures and derive a closed-form expression for the induced distribution of the random partition, the fundamental tool regulating the clustering behavior of the model. On the one hand, this allows to gain a deeper insight into the theoretical properties of the model and, on the other hand, it yields an MCMC algorithm for evaluating Bayesian inferences of interest. Moreover, we single out limitations of this algorithm when working with more than two populations and, consequently, devise an alternative more efficient sampling scheme, which as a by-product, allows testing homogeneity between different populations. Finally, we perform a comparison with the nested Dirichlet process and provide illustrative examples of both synthetic and real data.  相似文献   
933.
Abstract. Over recent years, the European Community has experienced profound demographic changes which, to a large extent, have already determined its demographic future. One of the more significant consequences of demographic and social trends is a marked fragmentation of the family with people giving absolute priority to the individual dimension in their lives and in terms of society as a whole. Legal regulations and administrative practice have not totally–and not everywhere – adapted to the far-reaching changes in the family so as to adequately protect the family and its weaker members in particular: children, the elderly, the disabled, people with mental and social illnesses, the poor. In this field, some measures will be proposed in this paper. The imbalances in demographic-occupational growth in the Euro-Mediterranean area–the area with which the EC is most directly in contact–are and will be of an exceptional amplitude, as has already been shown, to an extent never before experienced in the history of mankind. We must ask ourselves if this very strong differential pressure, which is also of a political and socio-economic nature, will lead to steady and long-lasting migratory flows. Some considerations regarding the future action and intervention of the EC close the paper.  相似文献   
934.
Perinatally HIV-infected (PHIV+) youth are surviving into adolescence and young adulthood. Understanding the sexual development of PHIV+ youth is vital to providing them with developmentally appropriate HIV-prevention programs. Using pooled data (N = 417) from two longitudinal studies focused on HIV among youth (51% female; 39% HIV+) and their caregivers (92% female; 46% HIV+), the rate of sexual onset during adolescence across four youth-caregiver combinations was compared: PHIV+ youth with HIV+caregivers (12%), PHIV+ youth with HIV- caregivers (27%), HIV- youth with HIV+caregivers (34%), and HIV- youth with HIV- caregivers (27%). Youth with HIV- caregivers were more likely than other youth-caregiver groups to have had their sexual onset. Youth with HIV+ caregivers reported a slower rate of onset of penetrative sex across the adolescent years. Findings are discussed by highlighting the role that both youth and caregiver HIV status play in the onset of sexual behavior across adolescence.  相似文献   
935.
This paper studies the relationship between having a disability and unemployment duration by focusing on individuals registered at Portuguese job centers. Despite its relevance, because disabled people are likely to occupy disadvantaged positions in the labor market, it has received little attention in the literature. As different disabilities affect unemployment duration differently, we distinguish different types of disabilities and shed light on disability-specific support policies. We apply a discrete time hazard model with unobserved heterogeneity to microdata from the Instituto do Emprego e Formação Profissional, which are free from self-reporting problems in disability identification. We find lower reemployment probabilities for many groups of disabled people: individuals with impairment in general functions, disfiguring, speech and visual disorders, muscle-skeletal and other organ impairments experience the more disadvantaged positions. Decomposition analysis indicates that part of the disadvantage is due to differences in returns rather than to differences in characteristics. These findings suggest that the disadvantage of disabled people in the labor market is not only explained by a different distribution of characteristics but especially by the interaction of their characteristics with the work environment. Policy implications are discussed.  相似文献   
936.
The current study examined the differences in arousal (physiologically and subjectively) between gamblers and non-gamblers. Thirty students from a mid-sized university took part in the study for a chance to win money in a gambling task. Nearly half of the participants identified themselves as non-gamblers and slightly more than half of the participants considered themselves gamblers. Findings indicated that gamblers experienced a significantly higher increase in physiological arousal (heart rate) compared to non-gamblers during the gambling experience. The results suggests the possibility that physiological arousal may play a role in the appeal of gambling to certain types of people. Furthermore, when gamblers suffered a loss at the end of the game, they reported feeling worse as compared to the non-gamblers and relative to their state before playing. Moreover, this affective change explained 28.6% of the variance in gambling behavior according to self-reports. Findings suggest that gamblers in our study may have been more personally invested in the gambling tasks, such that losing was more disappointing to the habitual gamblers than the non-gamblers.  相似文献   
937.
This study examined the effects of cumulative risk and promotive factors on violent behavior across the high school years of adolescence in a sample of predominately African American urban adolescents (N = 750). Cumulative risk and promotive factor indices represented individual characteristics, and peer, parental, and familial influences. Using growth curve modeling, we describe trajectories of cumulative risk and promotive factors and test the associations between the time‐varying cumulative risk and promotive factor indices and violent behavior. Higher risk was associated with higher levels of violent behavior. Higher levels of promotive factors were associated with less violent behavior and moderated the association between risk and violent behaviors. The results support the risk‐protective model of resiliency. Implications for prevention are discussed.  相似文献   
938.
939.
940.
The adequacy of facilities and the individual securities in their different age groups is importance to ensure greater functionality to them, allowing full development of daily activities. For this to occur more efficiently it is necessary the use of ergonomics which can ensure more comfort and safety for end users of products and spaces. The present study aimed to measure body dimensions of a representative sample of children aged 6 to 11 years old, children of graduate and pos graduate students, faculty and staff of the Federal University of Vicosa and also residents of the city of Vicosa, State of Minas Gerais, Brazil, coming from different municipalities of State of Minas Gerais, to organize a database that will provide the furniture industry, anthropometric variables more appropriate to design products for both the leisure activities, and for the school sector. To realize this research we used the methodology proposed by the authors Panero and Zelnik, based on samples distributed in six age groups, and providing a measurement of 10 variables. By applying the methodology to the field was possible to compare the observed data, with the tables of the aforementioned authors. The main results revealed a significant variation of the 10 variables analyzed, and it is believed that this variation could lead to possible flaws in the designs of products that use the data from these authors. The completion of the study provided data on Vicosa considered more appropriate for the design of products and environments for the population of the study, considering age and region, of Brazil (State of Minas Gerais) and it is believed that the future may expand to the Brazilian population, with the progress of study of this nature.  相似文献   
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