全文获取类型
收费全文 | 19444篇 |
免费 | 346篇 |
国内免费 | 1篇 |
专业分类
管理学 | 2787篇 |
民族学 | 75篇 |
人才学 | 1篇 |
人口学 | 1886篇 |
丛书文集 | 78篇 |
教育普及 | 2篇 |
理论方法论 | 1738篇 |
现状及发展 | 1篇 |
综合类 | 260篇 |
社会学 | 9427篇 |
统计学 | 3536篇 |
出版年
2021年 | 113篇 |
2020年 | 283篇 |
2019年 | 382篇 |
2018年 | 445篇 |
2017年 | 608篇 |
2016年 | 476篇 |
2015年 | 353篇 |
2014年 | 458篇 |
2013年 | 3028篇 |
2012年 | 642篇 |
2011年 | 617篇 |
2010年 | 449篇 |
2009年 | 371篇 |
2008年 | 446篇 |
2007年 | 463篇 |
2006年 | 458篇 |
2005年 | 446篇 |
2004年 | 413篇 |
2003年 | 385篇 |
2002年 | 424篇 |
2001年 | 519篇 |
2000年 | 532篇 |
1999年 | 464篇 |
1998年 | 341篇 |
1997年 | 311篇 |
1996年 | 329篇 |
1995年 | 303篇 |
1994年 | 285篇 |
1993年 | 289篇 |
1992年 | 346篇 |
1991年 | 316篇 |
1990年 | 285篇 |
1989年 | 291篇 |
1988年 | 290篇 |
1987年 | 252篇 |
1986年 | 244篇 |
1985年 | 278篇 |
1984年 | 266篇 |
1983年 | 252篇 |
1982年 | 216篇 |
1981年 | 180篇 |
1980年 | 165篇 |
1979年 | 195篇 |
1978年 | 177篇 |
1977年 | 159篇 |
1976年 | 135篇 |
1975年 | 157篇 |
1974年 | 118篇 |
1973年 | 116篇 |
1972年 | 93篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
891.
This paper presents the Ergonomic Work Analysis method in a Brazilian Dentist's office. Through the study, the constraints and the strategies in avoiding them were identified. It was found that dentists hardly use the position most indicated by the International Organization for Standardization (ISO) and the Federation Dentaire Internacionale (FDI) for both the patient and the dentist, which is respectively supine and 9 o'clock, due to the limited space and layout. Five types of treatments performed by the professional have been studied. The frequency and duration of actions in these treatments were accounted for and the standard positions adopted were identified. The AET was found to be a very suitable method to grasp the dentist's activity and build a point of view of the profession, which is characterized as: stressful, perfectionist and restrictive. Time management is presented as an important strategy to control the tension arising from performing the treatments. 相似文献
892.
Comfort is an issue that has gained relevance within the aeronautical industry due to the necessity of manufacturers and airline companies of differentiating themselves in a market that has become more and more competitive each day. This study's aim is to analyze the comfort/discomfort of passengers, based on the analysis of the activities performed in the aircrafts' cabin during real flights, in order to create ergonomics requirements and a methodology of comfort analysis. The study has been performed during domestic commercial flights, and the adopted data collection techniques have been: the application of 219 questionnaires to passengers, 44 registrations of postures and actions through filmings and 12 semistructured interviews. The method has made possible the reconstruction of the user's action course in performing activities in real flight situations, and the calculation of the area occupied by the passenger during his or her actions. The integrated analysis of the results corroborates data from previous studies in which both the space made available to each passenger and the activity performed interfere in their perception of comfort. From this study it has been concluded that the method constitutes itself as an innovative tool within the process of aircrafts' cabins project enabling the calculation of the action space based on the reconstructed course. 相似文献
893.
Sexual abuse of children has been a topic of scientific investigation for the past few decades. Research in this area, however, is rarely initiated, conceptualized, and conducted by victims themselves. Apart from possibly having painted a one-sided picture of sexual abuse, this presumed dominance of nonvictims might also have marginalized victims in a research area central to their lives. This study was conducted by a victims interest group as an effort to meet the need to add victims' perspectives to our current understanding of this topic. The online survey focused on investigating victims' psychosocial impairment, which was found to be extensive. Results indicated that an intact social support system facilitates better health, especially when offered early on. 相似文献
894.
Jørgen Drud Hansen Hassan Molana Catia Montagna Jørgen Ulff-Møller Nielsen 《Journal of Socio》2012,41(3):317-326
We examine how openness interacts with the coordination of consumption–leisure decisions in determining the equilibrium working hours and wage rate when there are leisure externalities (e.g., due to social interactions). The latter are modelled by allowing a worker's marginal utility of leisure to be increasing in the leisure time taken by other workers. Coordination takes the form of internalising the leisure externality and other relevant constraints (e.g., labour demand). The extent of openness is measured by the degree of capital mobility. We find that: coordination lowers equilibrium work hours and raises the wage rate; there is a U-shaped (inverse-U-shaped) relationship between work hours (wages) and the degree of coordination; coordination is welfare improving; and, the gap between the coordinated and uncoordinated work hours (and the corresponding wage rates) is affected by the extent and nature of openness. 相似文献
895.
Natalia V. Czap Hans J. Czap Marianna Khachaturyan Gary D. Lynne Mark Burbach 《Journal of Socio》2012,41(5):642-653
This paper further tests dual interest theory and the metaeconomics approach to environmental choice, recognizing a possible role for empathy–sympathy (the basis for an internalized, shared other-interest) in tempering and conditioning the more fundamental tendency to pursue self-interest. To test, we focus on rivers flowing through agricultural areas carrying sediments, chemicals, and fertilizers which are making their way into downstream rivers and lakes. We conduct a framed laboratory experiment modeling this problem: farmers decide on the usage of conservation technology to lessen impacts on the water quality (i.e. on the commons, the capacity to absorb these wastes) in downstream areas, which is more costly than the alternative intensive technology. The results confirm our hypotheses, demonstrating that Upstream Farmers who practice conservation are tempering profit maximization with empathy-based, environmentally conscious behavior. Such behavior better serves the farmers’ own-interest, and also helps Downstream Water Users. Environmental economics models need to explicitly include empathy–sympathy and the moral–ethical context it produces, providing a more scientific basis for conservation policy and programs. 相似文献
896.
Neeta S. Bijoor Heather R. McCarthy Dachun Zhang Diane E. Pataki 《Urban Ecosystems》2012,15(1):195-214
In semi-arid cities, urban trees are often irrigated, but may also utilize natural water sources such as groundwater. Consequently,
the sources of water for urban tree transpiration may be uncertain, complicating efforts to efficiently manage water resources.
We used a novel approach based on stable isotopes to determine tree water sources in the Los Angeles basin, where we hypothesized
that trees would rely on irrigation water in the soil rather than develop deep roots to tap into groundwater. We evaluated
the oxygen (δ18O) and hydrogen (δD) isotope ratios of xylem water, irrigation water, soil water, and groundwater in a study of temporal patterns
in water sources at two urban sites, and a study of spatial patterns at nine urban sites and one “natural” riparian forest.
Contrary to our hypothesis, we found that despite frequent irrigation, some trees tap into groundwater, although in most species
this was a small water source. Some trees appeared to be using very shallow soil water at <30 cm depth, suggesting that these
mature urban trees were quite shallowly rooted. In the natural site, trees appeared to be using urban runoff in addition to
shallow soil water. We were able to identify tree uptake of precipitation at only 3 sites. The results show that some irrigated
trees utilize groundwater and do not rely solely on irrigation water, which may make them able to withstand drought and/or
water conservation measures. However, some irrigated trees may develop very shallow root systems, which may make them more
susceptible. 相似文献
897.
LAURENT C. GLIN ARTHUR P. J. MOL PETER OOSTERVEER SIMPLICE D. VODOUHÊ 《全球网;跨国事务杂志》2012,12(3):333-354
In this article, we attempt to conceptualize the historical development and the governance structure of the transnational organic cotton network from Benin. We aim to discover how the organic cotton production‐consumption network is governed locally and internationally. Existing bodies of literature on international agricultural production networks, in particular the Global Value Chains (GVC) perspective, focus on economic dimensions, but find it difficult to incorporate the sustainability dimension. We favour widening the concept of GVCs beyond economics by acknowledging and including environmental rationalities and the representatives of their interests, not as external elements, but rather as co‐governing or co‐structuring factors (or actors) of sustainable value chains. Our findings reveal that beyond the traditional producer versus buyer dualism, intermediate stakeholders, namely transnational and local environmental NGO networks, are instrumental in the construction, maintenance and transformation of the organic cotton network. It is also apparent that farmers' leaders play an important role in mediating and (re)building trust among organic farmers, though they exert insufficient vertical power in the organic cotton network to control it. 相似文献
898.
899.
Non-hormonal approaches to premenstrual syndrome (PMS) treatment such as selective serotonin reuptake inhibitors are by no means effective for all women and frequently we must resort to endocrine therapy. During many of the hormonal approaches, PMS-like symptoms can be introduced or re-introduced during the necessary cyclical or continuous progestogen component of the therapy. This is seen with combined oral contraception, progestogen only contraception, progestogen therapy for heavy menstrual bleeding and endometriosis, sequential hormone replacement therapy and any therapeutic strategy for premenstrual syndrome where it is necessary to provide endometrial protection, including estrogen suppression of ovulation or add-back during gonadotrophin releasing hormone suppression. The link to progestogen is very often missed by health professionals. When the pattern of symptoms mimics the cyclicity of PMS, it is termed progestogen-induced premenstrual disorder. The need to use progestogen to protect the endometrium from the proliferative actions of estrogen can pose insurmountable difficulties in managing premenstrual disorders. In the absence of any really useful evidence, nearly all practice in this area depends on clinician experience. We cannot afford to wait for adequate research evidence to be produced - it never will - and so we must rely on empirical findings, clinical experience, theoretical strategies and common sense. 相似文献
900.
Janevic MR Janz NK Kaciroti N Dodge JA Keteyian SJ Mosca L Clark NM 《Journal of women & aging》2010,22(4):255-272
Using behavioral self-regulation processes may facilitate exercise among older women with heart disease. Data from women in a heart disease-management program (n = 658, mean 73 years), was used to explore associations among exercise self-regulation components (i.e., choosing to improve exercise and observing, judging, and reacting to one's behavior) and exercise capacity. General linear models showed that choosing exercise predicted higher exercise self-regulation scores postprogram and 8 months later. In turn, these scores predicted greater improvements in exercise capacity concurrently and 8 months later. Interaction analyses revealed that the effect of self-regulation on exercise capacity was stronger among women who chose to work on exercise. 相似文献