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891.
892.
Anne C. Petersen Pamela A. Sarigiani Robert E. Kennedy 《Journal of youth and adolescence》1991,20(2):247-271
Although there has been evidence for some time of a sex difference in depression, relatively little research has examined the developmental process by which women come to be at greater risk than men for depression. In this paper, the developmental pattern of depressed affect is examined over early and middle adolescence, with a special focus on the patterns of boys as compared to girls. In addition, a developmental model for mental health in adolescence is tested for its power in explaining the emergence of gender differences in depression. Longitudinal data on 335 adolescents randomly selected from two school districts were used to test the hypotheses. Results revealed that girls are at risk for developing depressed affect by 12th grade because they experienced more challenges in early adolescence than did boys. The sex difference in depressed affect at 12th grade disappears once early adolescent challenges are considered.This research was supported in part by grants MH30252/38142 to A. Petersen. We gratefully acknowledge the contributions of study participants and staff. Portions of this material were presented in a symposium at the 1988 meeting of the Society for Research on Adolescence, and one at the 1989 meeting of the Society for Research in Child Development.Received Ph.D. from University of Chicago in 1973. Research interest in biopsychosocial development in adolescence, with a focus on sex differences in mental health.Research interests include adolescent mental health, and parent and peer relationships.Received Ph.D. in psychology from The Pennsylvania State University. Research interests include development of affective and conduct disorders, especially sex differences in these problems. 相似文献
893.
894.
Transactions costs and the optimal instrument and intensity of air pollution control 总被引:2,自引:0,他引:2
Robert E. Kohn 《Policy Sciences》1991,24(4):315-332
Conclusions To what extent do the transactions costs of implementing alternative instruments for pollution control affect the choice of the optimal instrument and the efficient intensity of control under that instrument? In a comparison of Least-Cost Regulatory Standards and Revenue-Neutral Pigouvian Taxes, it is the higher transactions costs of implementing the taxes that make Pigouvian Taxes the more costly of the two instruments. However, a more practical comparison of instruments is between Politically Feasible Standards, Marketable Discharge Permits, and Revenue-Raising Pigouvian Taxes. Here, the relationship between the transactions costs of implementation and total pollution costs are in an almost linear inverse relationship. The lower the pollution costs associated with a particular instrument, and therefore the more desirable the instrument, the higher the transactions costs of implementation. Other factors such as political distortion and welfare gains prove to be more important than the transactions costs of implementation.Assuming that variable transactions costs decrease with the optimal level of pollution for regulatory standards but increase with the optimal level for market oriented instruments, an accounting of transactions costs results in less stringent control in the case of regulatory standards and more stringent control in the case of market oriented instruments. However, the percentage effect is very small. Moreover, it is smaller in both cases if marginal pollution damage rises with the level of pollution, as it is usually presumed to do, rather than remain constant as assumed in this paper for purposes of aggregation. A major conclusion of this paper is that Pigouvian Taxes are the superior instrument for pollution control when the raising of public revenues is a desired objective. However, the various conclusions of this paper should be viewed as tentative because the data on which they are based are no longer current. Moreover, the critical estimates of transactions costs are somewhat dubious. It is hoped that new data will be collected for answering the questions raised in this paper. When this is done, a more powerful approach, one that obviates the need for the artificial, one-dollar-damaging, aggregate pollutant, would be an expanded linear programming model in which the transactions costs are treated as separate coefficients of the individual pollution control methods. Separate sets of such coefficients, each corresponding to a different policy instrument such as Least-Cost Regulatory Standards, Revenue-Neutral Pigouvian Taxes, etc., would enable the investigator to directly derive solutions that specify the optimal policy instrument as well as the optimal set of pollution control method activity levels.I am grateful to William Ascher, Murray Weidenbaum, and two anonymous referees for helpful guidance on the paper. 相似文献
895.
The boundaries between selves and within selves are notions that have been subject to constant readjustment in the debates between liberals and communitarians. Through the archetype theories of Rawls, Nozick, Sandel and Parfit this essay re-enacts the deconstruction of one of the intuitive certainties of earlier liberal thought. Counterintuitive alliances are struck across the liberal-communitarian divide in demonstrating that the impersonality required by any theory of justice puts pressure on every notion of personality within it. Parfit radicalizes the problem of identity for everyone, permitting us to view old problems from new perspectives. 相似文献
896.
897.
A. J. Fischer 《Electoral Studies》1991,10(4)
It is usual for electoral analysts to calculate the swing necessary at the next election to unseat a government, assuming that the swing is a uniform one. However, swings are not uniform. The non-uniform swing which would, on average, unseat a government is shown to be different from the uniform swing. For example, at the next Australian election for the House of Representatives, a uniform swing of 1.5 per cent against the current government would cause it to lose five seats, leaving it in a minority of 73 out of 148 seats, but a non-uniform swing of only 0.8 per cent would, on average, have the same effect. Implications of this variability for the size of the majority, the possibilities of a Parliament with an even number of seats being equally-divided, and the use of this analysis to detect gerrymandering and to correct for it, are considered. 相似文献
898.
899.
900.