全文获取类型
收费全文 | 4332篇 |
免费 | 120篇 |
国内免费 | 3篇 |
专业分类
管理学 | 491篇 |
民族学 | 26篇 |
人口学 | 387篇 |
丛书文集 | 26篇 |
理论方法论 | 314篇 |
综合类 | 86篇 |
社会学 | 1899篇 |
统计学 | 1226篇 |
出版年
2023年 | 29篇 |
2022年 | 20篇 |
2021年 | 24篇 |
2020年 | 73篇 |
2019年 | 132篇 |
2018年 | 116篇 |
2017年 | 198篇 |
2016年 | 117篇 |
2015年 | 101篇 |
2014年 | 120篇 |
2013年 | 916篇 |
2012年 | 145篇 |
2011年 | 114篇 |
2010年 | 79篇 |
2009年 | 102篇 |
2008年 | 96篇 |
2007年 | 85篇 |
2006年 | 73篇 |
2005年 | 75篇 |
2004年 | 68篇 |
2003年 | 57篇 |
2002年 | 85篇 |
2001年 | 90篇 |
2000年 | 76篇 |
1999年 | 89篇 |
1998年 | 76篇 |
1997年 | 66篇 |
1996年 | 58篇 |
1995年 | 76篇 |
1994年 | 55篇 |
1993年 | 58篇 |
1992年 | 68篇 |
1991年 | 68篇 |
1990年 | 74篇 |
1989年 | 61篇 |
1988年 | 43篇 |
1987年 | 44篇 |
1986年 | 50篇 |
1985年 | 55篇 |
1984年 | 56篇 |
1983年 | 41篇 |
1982年 | 37篇 |
1981年 | 33篇 |
1980年 | 40篇 |
1979年 | 45篇 |
1978年 | 37篇 |
1977年 | 26篇 |
1976年 | 21篇 |
1974年 | 21篇 |
1971年 | 21篇 |
排序方式: 共有4455条查询结果,搜索用时 953 毫秒
121.
Cronce JM Corbin WR Steinberg MA Potenza MN 《Journal of gambling studies / co-sponsored by the National Council on Problem Gambling and Institute for the Study of Gambling and Commercial Gaming》2007,23(4):363-375
The relative influence of perceived familial addictive behaviors and personal gambling behaviors on adolescents' self-perceptions of gambling problems was examined. Students from five high schools in Connecticut (N = 3,886) were surveyed. Of those between the ages of 14 and 17 who scored two or more on the South Oaks Gambling Screen--Revised for Adolescents (n = 532; 72% male; 43% Caucasian), 14.3% reported having a current or past problem with gambling. Wagering larger amounts in a single day, gambling on a daily basis, and perceived presence of a family member with a gambling problem were associated with increased odds of self-perception of a gambling problem. Thus, adolescents who may be less likely to be identified for prevention efforts (due to lack of engagement in high stakes gambling or the real/perceived absence of a problematic gambler in the home) appear less likely to perceive a gambling problem. To advance prevention and treatment strategies, the apparent discrepancy between adolescents' self-perceptions and objective reports of problem gambling behaviors warrants further investigation. 相似文献
122.
123.
As demographic shifts make the Social Security program financially vulnerable, the responsibility for income security in old age will shift from the government to elderly people. In this changing environment, the accumulation of wealth will be a crucial issue because wealth holders can draw income from assets, which can supplement retirement income. Thus, wealth (or net worth) is a proximate indicator of economic well-being of the elderly. This article presents the findings of a study of the net worth of elderly people with disabilities. The major findings were that a smaller proportion of elderly people with disabilities has assets of any type compared with elderly people with no disability; the dollar value of each type of asset is smaller among elderly people with disabilities than among elderly people with no disability; and the net worth of people with disabilities is smaller than that of elderly people with no disability even after other variables were controlled. 相似文献
124.
Lees E Taylor WC Hepworth JT Feliz K Cassells A Tobin JN 《Journal of aging and physical activity》2007,15(4):425-438
Despite the numerous benefits of physical activity, older adults continue to be more sedentary than their younger counterparts, and sedentary behavior is more prevalent among older racial and ethnic minorities than among Whites. This study used the nominal group technique (NGT) to examine participants' perceptions of what neighborhood environmental changes would encourage greater physical activity for older African American and Hispanic women. Participants age 50-75 years were recruited from 2 urban community health clinics. Nine NGT sessions (45 participants) were conducted. The women were asked what changes in their neighborhood environment would encourage them to become more physically active. Responses to the research question were tabulated, and qualitative analysis was used to identify themes and categories. Major categories were physical environment changes, safety, and activities/social support. Although the physical environment received the greatest number of points, concerns for personal safety cut across categories. Participants indicated the need for more facilities in which to be active. 相似文献
125.
The purpose of this study was to determine the degree to which a novel training program based on activities of daily living (ADL) would affect performance of ADLs, as well as the fitness of older adults. Fourteen individuals (mean age 82 years) took part in a 10-week control period followed by a 10-week ADL-based training program. Pre- and posttests included the Physical Performance Test (PPT), the Physical Functional Performance-10 (PFP-10), and the Senior Fitness Test (SFT). After the training period, improvements ranging from 7% to 33% (p<.05) were seen on the PPT and PFP-10 and on three items of the SFT. After conversion to standard scores, the magnitude of change in the PPT and the PFP10 was significantly greater (p<.05) than the magnitude of change in the SFT. These data support the idea that this novel ADL-based training program was able to facilitate improved performance of ADLs, as well as select measures of fitness among older adults. 相似文献
126.
University research administrators have been generally ignored in basic studies of research integrity. Hensley noted that research administrators are "essential... to the achievement of the specific missions of postsecondary institutions... and to science and the academic infrastructure". The following study sought to extend the scope of research on research integrity to research administrative structures with a new instrument called the Research Environment Norm Inventory or RENI. University research administrators and their professional association were targeted for data collection. Evidence suggested that research administration in the United States supports integrity in the research environment through: (1) respect for community; (2) respect for institutional boundaries; (3) professionalism; (4) respect for authority structures; (5) sensitivity to system conflicts. The study suggested that integrity structures are dictated largely by the institutional settings and environments. 相似文献
127.
Virtual Interpersonal Touch and Digital Chameleons 总被引:1,自引:0,他引:1
We studied the characteristics of hand touch with a mechanical device that approximated a handshake, and we then examined
the effect of handshake mimicry on assessment of a partner. Two participants interacted with a force-feedback joystick that
recorded each of their hand movements individually. The two participants then greeted one another by feeling the recording
of the other person’s movements via the force-feedback device. For each dyad, one of the participants actually received his
or her own virtual handshake back under the guise that it was the other person’s virtual handshake. Results demonstrated three
significant findings. First, for any given participant, a metric that took into account position, angle, speed, and acceleration
of the hand movements correlated highly within individuals across two handshakes. Second, across participants, these metrics
demonstrated specific differences by gender. Finally, there was an interaction between gender and mimicry, such that male
participants liked people who mimicked their handshakes more than female participants did. We discuss the implications of
these findings and relate them to theories of social interaction.
相似文献
Jeremy N. BailensonEmail: |
128.
This paper analyzes the cost increases due to demand uncertainty in single-level MRP lot sizing on a rolling horizon. It is shown that forecast errors have a tremendous effect on the cost effectiveness of lot-sizing techniques even when these forecast errors are small. Moreover, the cost differences between different techniques become rather insignificant in the presence of forecast errors. Since most industrial firms face demand uncertainty to some extent, our findings may have important managerial implications. Various simulation experiments give insight into both the nature and the magnitude of the cost increases for different heuristics. Analytical results are developed for the constant-demand case with random noise and forecasting by exponential smoothing. It is also shown how optimal buffers can be obtained by use of a simple model. Although the analysis in this paper is restricted to simplified cases, the results merit further consideration and study. This paper is one of the first to inject forecast errors into MRP lot-sizing research. As such it attempts to deal with one of the major objections against the practical relevance of previous research in this area. 相似文献
129.
130.
Designing and integrating composite networks for monitoring multivariate gaussian pollution fields 总被引:2,自引:0,他引:2
J. V. Zidek W. Sun & N. D. Le 《Journal of the Royal Statistical Society. Series C, Applied statistics》2000,49(1):63-79
Networks of ambient monitoring stations are used to monitor environmental pollution fields such as those for acid rain and air pollution. Such stations provide regular measurements of pollutant concentrations. The networks are established for a variety of purposes at various times so often several stations measuring different subsets of pollutant concentrations can be found in compact geographical regions. The problem of statistically combining these disparate information sources into a single 'network' then arises. Capitalizing on the efficiencies so achieved can then lead to the secondary problem of extending this network. The subject of this paper is a set of 31 air pollution monitoring stations in southern Ontario. Each of these regularly measures a particular subset of ionic sulphate, sulphite, nitrite and ozone. However, this subset varies from station to station. For example only two stations measure all four. Some measure just one. We describe a Bayesian framework for integrating the measurements of these stations to yield a spatial predictive distribution for unmonitored sites and unmeasured concentrations at existing stations. Furthermore we show how this network can be extended by using an entropy maximization criterion. The methods assume that the multivariate response field being measured has a joint Gaussian distribution conditional on its mean and covariance function. A conjugate prior is used for these parameters, some of its hyperparameters being fitted empirically. 相似文献