首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   11963篇
  免费   209篇
管理学   1699篇
民族学   58篇
人才学   2篇
人口学   1231篇
丛书文集   61篇
教育普及   1篇
理论方法论   1041篇
现状及发展   1篇
综合类   142篇
社会学   5662篇
统计学   2274篇
  2023年   83篇
  2021年   63篇
  2020年   183篇
  2019年   240篇
  2018年   276篇
  2017年   400篇
  2016年   302篇
  2015年   201篇
  2014年   258篇
  2013年   2058篇
  2012年   402篇
  2011年   332篇
  2010年   279篇
  2009年   267篇
  2008年   301篇
  2007年   287篇
  2006年   261篇
  2005年   260篇
  2004年   255篇
  2003年   233篇
  2002年   262篇
  2001年   297篇
  2000年   302篇
  1999年   281篇
  1998年   193篇
  1997年   176篇
  1996年   173篇
  1995年   170篇
  1994年   142篇
  1993年   158篇
  1992年   178篇
  1991年   151篇
  1990年   160篇
  1989年   184篇
  1988年   155篇
  1987年   139篇
  1986年   158篇
  1985年   180篇
  1984年   171篇
  1983年   164篇
  1982年   124篇
  1981年   108篇
  1980年   106篇
  1979年   137篇
  1978年   91篇
  1977年   91篇
  1976年   95篇
  1975年   87篇
  1974年   82篇
  1973年   75篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
Recent studies demonstrating a concentration dependence of elimination of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) suggest that previous estimates of exposure for occupationally exposed cohorts may have underestimated actual exposure, resulting in a potential overestimate of the carcinogenic potency of TCDD in humans based on the mortality data for these cohorts. Using a database on U.S. chemical manufacturing workers potentially exposed to TCDD compiled by the National Institute for Occupational Safety and Health (NIOSH), we evaluated the impact of using a concentration- and age-dependent elimination model (CADM) (Aylward et al., 2005) on estimates of serum lipid area under the curve (AUC) for the NIOSH cohort. These data were used previously by Steenland et al. (2001) in combination with a first-order elimination model with an 8.7-year half-life to estimate cumulative serum lipid concentration (equivalent to AUC) for these workers for use in cancer dose-response assessment. Serum lipid TCDD measurements taken in 1988 for a subset of the cohort were combined with the NIOSH job exposure matrix and work histories to estimate dose rates per unit of exposure score. We evaluated the effect of choices in regression model (regression on untransformed vs. ln-transformed data and inclusion of a nonzero regression intercept) as well as the impact of choices of elimination models and parameters on estimated AUCs for the cohort. Central estimates for dose rate parameters derived from the serum-sampled subcohort were applied with the elimination models to time-specific exposure scores for the entire cohort to generate AUC estimates for all cohort members. Use of the CADM resulted in improved model fits to the serum sampling data compared to the first-order models. Dose rates varied by a factor of 50 among different combinations of elimination model, parameter sets, and regression models. Use of a CADM results in increases of up to five-fold in AUC estimates for the more highly exposed members of the cohort compared to estimates obtained using the first-order model with 8.7-year half-life. This degree of variation in the AUC estimates for this cohort would affect substantially the cancer potency estimates derived from the mortality data from this cohort. Such variability and uncertainty in the reconstructed serum lipid AUC estimates for this cohort, depending on elimination model, parameter set, and regression model, have not been described previously and are critical components in evaluating the dose-response data from the occupationally exposed populations.  相似文献   
72.
This is a review of "the limited and scant contributions made to immigration theory in the context of the evolution of economic thought over a protracted historical time span." The economic theories considered include those of the mercantilists, Adam Smith, the classical economists, and J. M. Keynes. (SUMMARY IN FRE AND SPA)  相似文献   
73.
The expanding knowledge and skill bases within the interdisciplinary family therapy profession pose a significant challenge for evolving practitioners, at whatever stage along the professional development process they find themselves. This challenge raises a basic question regarding whether there are any constraining forces to the level of eclecticism in practice towards which one can aspire. This paper empirically explores the role played by the personality attributes of the family therapist in facilitating and/or inhibiting one's adherence to a variety of approaches to family practice.  相似文献   
74.
Research on family therapy training has produced very little data regarding the kinds of trainees that do best in family therapy training programs. This study attempts to provide some rough and preliminary data on that issue. One hundred and seventy trainees, drawn from seven different structural!strategic training experiences, were evaluated as to how much they learned by taking the Family Therapy Assessment Exercise pre- and posttraining. Their performance was correlated using a hierarchical regression analysis with a number of trainee variables such as amount of conjugal family experience, amount of experience doing family or individual therapy, or prior knowledge of family therapy. The results indicate that, as predicted, conjugal family experience was positively related, and prior knowledge was negatively related to performance. Prior experience doing individual therapy was also positively related to performance.  相似文献   
75.
Working with a treatment and observing team at the same time, behind the oneway mirror, offers a variety of ways to: (a) generate multiple realities; (b) work with two different models of family therapy simultaneously; and (c) provide feedback on the teams' own roles, rules and group process. The process that 6 trainees and two supervisors used with T and O teams to examine their own coevolution as a therapeutic system using the Milan model of family therapy and Ericksonian hypnotherapy is described. The article concludes with a discussion of the advantages and pitfalls of this type of dual supervision.  相似文献   
76.
An estimated 200,000-500,000 men, women, and children work in prostitution in the Philippines in a variety of venues, including brothels, nightclubs, pubs, massage parlors, and other legitimate entertainment establishments. Few, however, are voluntary prostitutes. Many people who work as prostitutes have been recruited from the provinces, kept in conditions similar to slavery, and forced to earn money from prostitution to pay for their transportation, board, and lodging. Many prostitutes work in urban centers and tourist resorts in the countryside. During the 1970s, then President Ferdinand Marcos promoted tourism as a major industry, effectively marketing attractive Filipinas to tourists. Sex tourism has flourished in the country ever since. Thousands of prostitutes are also located in Olongapo and Angeles, 2 cities north of Manila, from where they serve the sexual desires of US military personnel. The presence of US military personnel in the Philippines has always been associated with prostitution. The country's social hygiene centers, prostitutes in Manila and Davao, and AIDS education are briefly discussed.  相似文献   
77.
The internalization of clinical nursing research values, norms, and attitudes via orientation and research development, along with the introduction of research tools (artifacts), constitutes the birthing phase of the acculturation process. The development of unit and individual research agendas and the implementation of research rounds illustrates a "bonding phase," in that nurses are bonding or weaving research into the fabric of their clinical practice. The final phase, stabilization, occurs when clinical nursing research is core to clinical nursing practice as illustrated by rewards or sanctions via performance evaluations, and provisions for release time for research participation.  相似文献   
78.
Recent literature on migration, international relations, and foreign policy is reviewed in this article, stressing applications of global systems paradigms, studies of state entry and exit rules, and anatomies of domestic policy-setting processes on migration. After a concise assessment of the contemporary theory of global political economy, the paper argues for seeking mid-range generalizations on the international relations of migration. It also suggests that analysis begin with the policy-setting processes of the state. Especially through the use of comparative perspectives available from domestic policy making studies and from the field of international comparative public policy, this approach offers the opportunity to fix empirically the political roles of transnational social forces, which often present themselves as participants in domestic policy contests. Promising future directions in the study of state-to-state relations are also evaluated, with the anticipation that verifying regional or other intermediate patterns of world migration politics may contribute to more general theories of international political economy.  相似文献   
79.
2 evaluative views of worker remittances draw opposite conclusions. The negative one posits that remittances increase dependency, contribute to economic and political stability and development distortion, and lead to economic decline that overshadows a temporary advantage for a fortunate few. The positive view sees remittances as an effective response to market forces, providing a transition to an otherwise unsustainable development. They improve income distribution and quality of life beyond what other available development resources could deliver. The implications are tested for labor supply countries to Europe and the Middle East. The implications of the negative are not supported. Although the dire predictions of the pessimistic view have not materialized, the converse - contributions of remittances to economic performance - should not be overstated due to a lack of data.  相似文献   
80.
This paper clarifies and interprets some basic quantitative concepts of value, utility and utility function from a utilitarian point of view. First, I discuss the question as to whether value is objective or subjective. I hold that value is subjective and statistical in nature (although from the various subjective values of a certain object a norm can usually be obtained). Second, I emphasize the distinction between use value and exchange value in relation to utility. Third, I propose a law of diminishing incremental interest, which refers to the incremental (marginal) utility of money. Fourth, I identify the utility of money with the von Neumann-Morgenstern utility. Fifth, I question the necessity of the usual normalization of utility functions and the restricted linear transformation (and the consequent concept of strategic equivalence). Sixth, I discuss in detail the terminal values and utilities of a utility function from a philosophical rather than mathematical point of view, particularly the boundedness of a utility function and the magnitudes of V 0 and U 0. Finally, I conclude that, in order to be able to have interpersonal comparisons of utility, utility should have the same dimension as value rather than no dimension, and the normalization problem should be reconsidered in the light of terminal values and utilities.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号