全文获取类型
收费全文 | 7974篇 |
免费 | 121篇 |
国内免费 | 2篇 |
专业分类
管理学 | 1245篇 |
民族学 | 26篇 |
人口学 | 694篇 |
丛书文集 | 22篇 |
理论方法论 | 703篇 |
综合类 | 97篇 |
社会学 | 4015篇 |
统计学 | 1295篇 |
出版年
2020年 | 92篇 |
2019年 | 120篇 |
2018年 | 147篇 |
2017年 | 171篇 |
2016年 | 157篇 |
2015年 | 110篇 |
2014年 | 162篇 |
2013年 | 1336篇 |
2012年 | 187篇 |
2011年 | 203篇 |
2010年 | 153篇 |
2009年 | 151篇 |
2008年 | 191篇 |
2007年 | 182篇 |
2006年 | 197篇 |
2005年 | 188篇 |
2004年 | 158篇 |
2003年 | 129篇 |
2002年 | 150篇 |
2001年 | 155篇 |
2000年 | 179篇 |
1999年 | 143篇 |
1998年 | 141篇 |
1997年 | 124篇 |
1996年 | 132篇 |
1995年 | 133篇 |
1994年 | 142篇 |
1993年 | 133篇 |
1992年 | 143篇 |
1991年 | 157篇 |
1990年 | 173篇 |
1989年 | 145篇 |
1988年 | 160篇 |
1987年 | 136篇 |
1986年 | 136篇 |
1985年 | 134篇 |
1984年 | 147篇 |
1983年 | 133篇 |
1982年 | 98篇 |
1981年 | 81篇 |
1980年 | 87篇 |
1979年 | 114篇 |
1978年 | 91篇 |
1977年 | 71篇 |
1976年 | 84篇 |
1975年 | 54篇 |
1974年 | 77篇 |
1973年 | 52篇 |
1971年 | 43篇 |
1970年 | 45篇 |
排序方式: 共有8097条查询结果,搜索用时 15 毫秒
951.
Kimberly M. Thompson Radboud J. Duintjer Tebbens Mark A. Pallansch Olen M. Kew Roland W. Sutter R. Bruce Aylward Margaret Watkins Howard Gary James P. Alexander Linda Venczel Denise Johnson Victor M. Cáceres Nalinee Sangrujee Hamid Jafari Stephen L. Cochi 《Risk analysis》2006,26(6):1571-1580
The success of the Global Polio Eradication Initiative promises to bring large benefits, including sustained improvements in quality of life (i.e., cases of paralytic disease and deaths avoided) and costs saved from cessation of vaccination. Obtaining and maintaining these benefits requires that policymakers manage the transition from the current massive use of oral poliovirus vaccine (OPV) to a world without OPV and free of the risks of potential future reintroductions of live polioviruses. This article describes the analytical journey that began in 2001 with a retrospective case study on polio risk management and led to development of dynamic integrated risk, economic, and decision analysis tools to inform global policies for managing the risks of polio. This analytical journey has provided several key insights and lessons learned that will be useful to future analysts involved in similar complex decision-making processes. 相似文献
952.
A conceptual framework is presented in which mental load and stress are regarded as two distinct biobehavioural states in the work environment that differ in energy mobilization, mood and coping strategy. The framework combines two types of theory that are based on human performance research using laboratory tasks on the one hand and applied research in the work environment on the other. A high workload is regarded as an important but not a critical factor in the development of stress symptoms. Even under unfavourable conditions it is possible to work intensively and to be highly activated without feelings of strain or psychosomatic complaints. In contrast, working conditions that provide few possibilities for control and little social support or are associated with reduced well-being and increased health risks. The two states differ in activation, coping style and mood. A proper distinction is important not only for theory building but also for the reconstruction of the work environment. It may lead to recommendations that aim to enhance the work efficiency of employees while reducing the probability that stress responses will occur. 相似文献
953.
954.
This study analyses the effectiveness of the European Community's Environmental Assessment Directive of 1985 in its application in the U.K. forestry sector. It assesses the applicability of the regulations in the provision of the public and private outputs of forestry. The environmental assessment regulation may contribute to the provision of the optimal amount of these public and private goods in theory, but it is concluded that, in common with initial results of the environmental assessment process in other sectors, the regulations do not make this contribution in practice in the forestry sector. The main deficiencies of the environmental statements examined were the failure to identify the significant potential impacts; to present alternative project sites and design features; and the erroneous measure of particular externalities. The environmental assessment process was also found to be unsatisfactory in the lack of public accessibility and consultation. The need for revision of the process in the forestry sector is highlighted. 相似文献
955.
956.
Adam W. Kolkiewicz 《Revue canadienne de statistique》2003,31(3):329-347
The author shows how to find M‐estimators of location whose generating function is monotone and which are optimal or close to optimal. It is easy to identify a consistent sequence of estimators in this class. In addition, it contains simple and efficient approximations in cases where the likelihood function is difficult to obtain. In some neighbourhoods of the normal distribution, the loss of efficiency due to the approximation is quite small. Optimal monotone M‐estimators can also be determined in cases when the underlying distribution is known only up to a certain neighbourhood. The author considers the e‐contamination model and an extension thereof that allows the distributions to be arbitrary outside compact intervals. His results also have implications for distributions with monotone score functions. The author illustrates his methodology using Student and stable distributions. 相似文献
957.
Sometimes, in industrial quality control experiments and destructive stress testing, only values smaller than all previous ones are observed. Here we consider nonparametric quantile estimation, both the ‘sample quantile function’ and kernel-type estimators, from such record-breaking data. For a single record-breaking sample, consistent estimation is not possible except in the extreme tails of the distribution. Hence replication is required, and for m. such independent record-breaking samples the quantile estimators are shown to be strongly consistent and asymptotically normal as m-→∞. Also, for small m, the mean-squared errors, biases and smoothing parameters (for the smoothed estimators) are investigated through computer simulations. 相似文献
958.
959.
960.
This paper describes a medical social worker's efforts over one and a half years to help a client adjust to a neurological disorder. Prior to social work services, the young woman had never discussed her disability, which began in adolescence, with anyone outside the family, and communication within the family was seriously compromised by their perception of disability as a stigma. Lacking the opportunity to mourn the loss of her physical abilities, she became isolated and depressed, and acted out aggressive thoughts and fantasies within the family system. Social work intervention helped the client to re-work the original trauma of diagnosis, which led to the development of a healthier defensive structure and new coping mechanisms. 相似文献