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991.
对以M .2 7EMLA、M .2 6EMLA和Mark为砧的Liberty、NY7541 4— 1、NY74 82 8— 1 2、NY6570 7— 1 9和McShay等苹果品种的生长、早熟性、产量和果实大小等项目进行的研究表明 ,Liberty、McShay、NY74 82 8— 1 2的树体大于NY7541 4— 1、NY6570 7— 1 9的树体最小。就砧木而言 ,以Mark为砧的苹果品种树体大于以M .2 6为砧的 ,以M .2 7为砧的树体最小。本文中的品种和砧木对树体的生长的影响没有交互作用。NY74 82 8— 1 2在定植后第 3、4年花量最大 ,NY6570 7— 1 9的最少。 1 993年时以Mark为砧的树花量比以M .2 6的为最多 ,以M .2 7为砧的开花量最少。Liberty、NY7541 4— 1和NY74 82 8— 1 2的累计产量比McShay和NY6570 7— 1 9的高。以Mark为砧的树累计产量多于以M .2 6为砧的 ,以M .2 7为砧的品种产量最低。NY6570 7— 1 9果形最大 ,NY74 82 8— 1 2的最小。以M .2 7为砧的树所结果实比以M .2 6和Mark为砧的小。NY7541 4— 1的树势中庸 ,早熟 ,高产 ,产量效率高 ,果实大小适度。NY74 82 8— 1 2在本试验中的表现也较好 ,但它对苹果黑星病只具Vm抗性而不具Vf抗性 ,故不可能作为新品种定名。在这些抗病品种中 ,根据早熟性、树势、产量和果形大小来看 ,Liberty和NY7541 4— 1具最佳的商品生产潜力。以  相似文献   
992.
993.
本文论述了研究型大学在知识经济中的作用 ,阐述了研究型大学如何利用其自身优势通过协作及参与振兴企业文化以推动地区经济的进一步发展  相似文献   
994.
This study contributes to our knowledge on the association between parenthood and psychological well-being by examining whether pre-parenthood lifestyles (leisure and paid work) moderate the transition to parenthood. We expected that people with less active lifestyles would find it easier to adapt to the demands of parenthood. Using eleven waves of the Swiss Household Panel (N = 1332 men and 1272 women; 1999–2008, 2010), fixed effects models are estimated for men and women separately. Results show that—on average—parenthood was not associated with well-being for men, whereas it increased well-being for women. As expected, the well-being premium/cost to parenthood was contingent upon individuals’ lifestyle before the transition to parenthood. For men, parenthood reduced well-being, but only if they frequently participated in leisure before the birth of the child. For women, motherhood had a beneficial effect on well-being but this effect was weaker for women who combined leisure with working long hours before motherhood.  相似文献   
995.
现代国际贸易理论中的国内和国际规模收益   总被引:1,自引:0,他引:1  
在二战后的国际贸易中,工业化国家之间的制造业产品的交易量巨大,这种产业内贸易现象的出现,在一定程度上对传统的赫克歇尔-俄林-萨缪尔逊贸易模型产生了冲击和质疑。经济学家从多个角度寻求对这种现象的理论解释,并开始注意产品差别化及其对规模经济的影响,但是,这些研究对贸易理论的影响很小,并且解释现实的能力也很弱。因此,把差别化的生产资料作为研究的重点,在国际收益的框架下,建立模型以推出国际规模收益,并且运用这一模型得出了国际规模收益、传统的国内规模收益和要素禀赋论之间的关系。  相似文献   
996.
Leaders form different quality leader–member exchange (LMX) relationships with their subordinates. This variable treatment termed LMX differentiation can have negative effects on individuals' behavior and attitudes. In this study, we examined the cross-level main effect of justice climate on task performance and the moderating role of justice climate on the relationship between LMX differentiation and task performance. We tested these two hypotheses using a field study of 90 subordinates nested under 27 supervisors. Procedural justice climate, not distributive justice climate, was found to positively influence subordinate task performance. Further, distributive justice climate, not procedural justice climate, was found to moderate the LMX differentiation–task performance relationship; such that the relationship was positive when distributive justice climate was high and negative when distributive justice climate was low. Findings and future directions are discussed.  相似文献   
997.
The vast majority of research on the relationship between corporate governance and strategic management focuses on the impact of corporate governance on strategic management. In this article we propose a cyclical model, highlighting that strategic decisions can also affect corporate governance through shaping firm ownership structure. We discuss the impacts of strategic decisions on firm ownership structure and corporate governance in the contexts of publicly traded firms, private firms, and the privatization of state-owned enterprises. We hope that our cyclical model can promote researchers to develop a more complete view about the relationships between strategic management, ownership structure, and corporate governance.  相似文献   
998.
This paper provides a contemporary and comprehensive review of work in the marketing channel field that is based on French and Raven's power‐base theory. It traces the development of theoretic, conceptual and methodological orthodoxies from the 1970s. Mirroring the movement towards the relationship marketing paradigm, the paper considers the theory's empirical contribution to knowledge of power, conflict, trust and commitment in marketing channels. Limitations relating to inconsistency of treatment, contradictory findings and the simplification of complex phenomena are identified. Nevertheless, current work extends power‐base theory to other cultures, other styles of research and to the area of supply chains. The review raises questions about the value of contribution made using this theory and notes the surprising absence within the channels literature of the broader, current debate about power. To illustrate, the paper shows how Clegg's (1989. Frameworks of Power. London: Sage) circuits of power framework, if applied to channel contexts, could address forms of power that are invisible, anonymous and not necessarily negative. Applications and methods are discussed, opening a space wherein a broadened understanding of power is integrated within a focus upon cooperative channels.  相似文献   
999.
1000.
The use of thimerosal preservative in childhood vaccines has been largely eliminated over the past decade in the United States because vaccines have been reformulated in single‐dose vials that do not require preservative. An exception is the inactivated influenza vaccines, which are formulated in both multidose vials requiring preservative and preservative‐free single‐dose vials. As part of an ongoing evaluation by USFDA of the safety of biologics throughout their lifecycle, the infant body burden of mercury following scheduled exposures to thimerosal preservative in inactivated influenza vaccines in the United States was estimated and compared to the infant body burden of mercury following daily exposures to dietary methylmercury at the reference dose established by the USEPA. Body burdens were estimated using kinetic parameters derived from experiments conducted in infant monkeys that were exposed episodically to thimerosal or MeHg at identical doses. We found that the body burden of mercury (AUC) in infants (including low birth weight) over the first 4.5 years of life following yearly exposures to thimerosal was two orders of magnitude lower than that estimated for exposures to the lowest regulatory threshold for MeHg over the same time period. In addition, peak body burdens of mercury following episodic exposures to thimerosal in this worst‐case analysis did not exceed the corresponding safe body burden of mercury from methylmercury at any time, even for low‐birth‐weight infants. Our pharmacokinetic analysis supports the acknowledged safety of thimerosal when used as a preservative at current levels in certain multidose infant vaccines in the United States.  相似文献   
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