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241.
This paper describes some of the spinoff benefits that can result from R&D projects, and categorizes them in terms of the dimensions of market and technical newness. These dimensions are discussed with reference to two types of spinoffs: 1) alternative market applications, when the results of an R&D project are subsequently applied to a market or use that differs from the originally intended application, and 2) second-generation technologies, when the technology that was the subject of an R&D project is significantly altered or enhanced in unanticipated ways through subsequent R&D. Examples from the Department of Energy's Energy-Related Inventions Program are integrated into the results of literature review to illustrate key concepts, including core technologies, degrees of market and technology newness, technology robustness, and the nature of connections linking spinoffs to prior R&D investments. The paper concludes by discussing spinoffs as a managerial strategy. 相似文献
242.
243.
The “tragedy of the commons” is the familiar problem that open access to a common property resource leads to overexploitation and to zero profits. A commons model is applied to an example of state sponsored private violence, the practice of privateering or licensed piracy. It is predicted that the presence of uncertainty about the value of the prey will reduce the amount of exploitation effort, and that industry profits may be positive due to both uncertainty and heterogeneous exploiters. Using data from England's wars with France and Spain between 1625 and 1630, the model suggests that the commons, represented by enemy merchant shipping, was not overexploited and that privateering profits were positive. The dynamic paths of privateering effort, ships seized, and individual firm profits were, however, consistent with the normal expectation that commons exploitation will peak and fall, as competition drives down returns through entry. “England was never richer than when at war with Spain.” Sir Edward Coke 相似文献
244.
On 26 October 1992, a majority of Canadians in a majority ofprovinces rejected the Charlottetown Accord in a national referendum.The accord capped the "Canada round" of constitutional negotiationsand attempted to satisfy Quebec, while also addressing otherpan-Canadian issues. The accord was defeated for different reasonsin different parts of the country. In Quebec, the "No" sideargued that the agreement did not meet their demands for greaterjurisdictionalautonomy within the federation. In the rest of Canada, the "No"side was particularly successful in demonstrating that the agreementdeviated from the principle of equality in the treatment ofindividuals and provinces. These critiques, inspired by differentvisions of the federation, lead in different directions. Inlight of these divisions, many commentators have suggested thatintergovernmental elites ought to abandon efforts of wholesaleconstitutional change. However, political developments in Quebecmay force these questions back onto the agenda. 相似文献
245.
Gonzalez Cervera AS 《Estudios demográficos y urbanos》1993,8(2):287-306, 483-4
Data from the 1987 National Health and Fertility Survey were used to explore trends and differentials in unwanted fertility in Mexico. Women were classified in three educational categories: illiterate or incomplete primary, complete primary or some secondary, and complete secondary or more. The four urbanization categories were: under 2500; 2500 to 19,999; 20,000 and more; and metropolitan areas. The place of primary socialization was the place of residence until age 12. Two categories of employment of household head were included, agricultural or nonagricultural. The categories for mother's employment considered employment until the union and employment between the time of union and the birth of the first child. The proportion of births that were unwanted was estimated by calculating the total fertility rate for the year before the survey and comparing it to desired family size. The "total desired family size" was 2.4 for the entire sample. In other words, nearly 37% of the total fertility rate was undesired. The greatest differentials in percentages of undesired fertility were found in educational categories. 40.7% of the total fertility rate in the least educated groups vs. 13.6% in the most educated groups was undesired. Differentials in the other categories ranged from 1.9 for a history of employment before the birth of the first child to 8.8 for agricultural or nonagricultural employment of the household head. When effects of education were controlled, the percentage of undesired fertility declined as educational level increased for all rural or urban residence categories, places of socialization, and employment groups except women who worked before the first child was born. Women with more education, urban residence, and with histories of employment had the lowest levels of undesired fertility. 相似文献
246.
Wattelar C 《Estudios demográficos y urbanos》1993,8(2):415-425
The author reviews current demographic trends in the countries of the European Community in the light of the efforts to abolish frontiers and border controls among member countries. She shows that there has been a general trend toward commonality in many aspects of demographic behavior. 相似文献
247.
Flores C 《Estudios demográficos y urbanos》1993,8(2):361-76, 485
"Constitution of a trade bloc between Mexico, the United States and Canada through the North American Free Trade Agreement (NAFTA) in this decade has called attention to...the role of Mexico's southern border, Central American conflicts and migrations from that era. Relevant adjustments have been made to Mexico's policy in approaching problems regarding its southern neighbors. These changes respond largely to the perception held by larger economic blocs and migration generated by unequal development levels within these regions and countries." (SUMMARY IN ENG) 相似文献
248.
With Bill Clinton's new reforms only a month away, the health-care system is on the operating table--and the doctors are under the knife. Americans have a love-hate relationship with physicians: they like the care that doctors provide but hold them to blame for the nation's health-care mess. NEWSWEEK looks at how the culture of medicine may change, assesses doctors' fears--and examines the brave new world of HMOs. 相似文献
249.
250.
Measuring School-Related Stressors in Adolescents 总被引:2,自引:0,他引:2
Some 1620 high school students responded to 68 items that measure adolescent stressors. Thirty-five of the items were based on J. P. Kohn and G. H. Frazer's Academic Stress Scale [1(1986) An Academic Stress Scale: Identification and Rated Importance of Academic Stressors, Psychological Reports, Vol. 59, pp. 415–426] developed in the United States, while the remaining 33 items were developed from P. Strutynski's [(1985) A Survey of Queensland Year 10, 11 and 12 Student Attitudes to Schools and Schooling, State Planning Committee, International Youth Year, Brisbane] lists of the most frequently named problems of 2336 Australian high school students. Confirmatory Factor Analysis was used to test and develop a measurement model developed from an extensive review of previous scales. The High School Stressors Scale emerged from the analytic process and measures nine school-related stressors. For researchers focusing on school-related problems and stressors among adolescents, the HSSS promises to be a very useful instrument. It has sound construct and predictive validity and adequate reliability, as demonstrated by the goodness-of-fit indices the squared multiple correlations. 相似文献