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291.
We confirm the existence of oviposition-deterring, fruit-marking pheromones inRhagoletis pomonella andR. fausta and demonstrate their existence in five additional species:R. cingulata, R. indifferens, R. mendax, R. cornivora andR. tabellaria. Individuals from (1) different species belonging to different species groups did not recognize each other's marking pheromones,
(2) different species within the same species group varied in reaction from complete to no cross-recognition, (3) different
wild populations of the same species always recognized each other's marking pheromones, and (4) a laboratory population ofR. pomonella cultured on apples for ca. fifteen generations deposited a marking pheromone less deterrent to oviposition than that from
a wild population. Finally, the watersoluble marking pheromones ofR. indifferens andR. cornivora proved effective deterrents to oviposition when collected and reapplied in aqueous solution to uninfested fruit in laboratory
cages.
Zusammenfassung Bei fünfRhagoletisarten wird der Nachweis von Eiablage-abschreckenden, Frucht-markierenden Pheromonen zum ersten Mal geführt:R. cingulata, R. indifferens, R. mendax, R. cornivora undR. tabellaria. Damit erh?ht sich die Zahl vonRhagoletisarten auf neun und die Zahl von pflanzenparasitischen Insektenarten auf zehn, bei denen derartige Pheromone bekannt sind. Wenn Glieder dieser fünf Arten und zus?tzlich vonR. pomonella undR. fausta untersucht wurden auf den Grad des Interpopulation-und innerartlichen Erkennens der Markierungspheromone, so ergab sich: 1. Verschiedene Populationen der selben Art erkennen untereinander die Pheromone, unabh?ngig von Wirt und Herkunft; 2. Verschiedene Arten innerhalb der gleichen Artengruppe variieren in ihrer Reaktion zwischen vollst?ndigem, teilweisem und fehlendem krouzweisen Pheromon-Erkennen; und 3. Verschiedene Arten von verschiedenen Artengruppen erkennen nicht gegenseitig ihre Pheromone, auch wenn sie von Wirten gleicher Gattung oder Art kommen. — Die bisher nicht identifizierten, wasserl?slichen Markierungspheromone vonR. indifferens undR. cornivora erwiesen sich als stark Eiablage-abschreckend, wenn sie von markierten Früchten gewonnen und in w?ssriger L?sung bei unbefallenen Früchten in Labork?figen wieder angewendet wurden.相似文献
292.
Ronald John Hy Douglas Feig Robert M. Regoli 《American Journal of Criminal Justice》1984,8(2):195-213
Most criminal justice administrators can no longer rely on a single problem solving technique. Consequently, effective administrators
must become familiar with (though no experts in) various techniqes. Linear programming (LP) is a powerful managerial technique
which provides narrow-range solutions to problems in which the impact of key variables is both linear and certain. LP is especially
useful when applied to problems involving the allocation of limited resources. This article discusses a simple how-to appraoach
to LP, which is a mathematical problem solving computation that provides solutions which can be applied under conditions of
certainty. Besides defining the key characteristics of LP, this article illustrates the procedures used to calculate the simplex
method, the most widely used method for calculating a set of LP equations. The simplex method is mathematically efficient
because it considers only the best solutions with a minimum number of solutions computed. Once the solution is computed, it
is relatively easy to interpret the computer output. 相似文献
293.
Gay W. Seidman Ronald H. Chilcote Stanley A. Kochanek Raymond Clémencon Roderic A. Camp Wilfred L. David Stephen M. Smith Theodore Panayotou Norman Rask David G. Abler Richard L. Clinton Hooshang Amirahmadi Charles D. Brockett 《Studies in Comparative International Development (SCID)》1989,24(3):70-96
294.
295.
Ronald N. Kostoff 《The Journal of Technology Transfer》1997,22(3):3-8
Conversion of science to technology typically represents a transition across cultures, organizations, time scales, perspectives, personal motivations and philosophies. The purpose of this special issue is to address the specific problem of efficient and effective conversion of science to technology. This special issue will focus on the ideas, concepts and principles (for improving the science to technology conversion) that can be derived from past and present practices, and will complement recent special journal issues on Research Impact Assessment (Evaluation Review, February 1994) and Performance Measures for Government Sponsored Research (Scientometrics, July–August 1996). The theme that permeates this special issue is that efficient science to technology conversion is a contact sport. It is critical that interested parties (from each side of the science-technology barrier) develop early awareness of, and subsequent early involvement in, each other's culture, problems, and potential to maximize opportunities for removing impediments to successful transition. Awareness and involvement can be greatly enhanced through the use of the latest findings and tools resulting from advances in information science and technology. The various papers in this special issue present concepts and successful examples for enhancing mutual awareness and deepening the breadth and period of involvement that eventually result in transition obstacle removal. 相似文献
296.
This paper describes the Graphical Modeling System, a computer-based process for generating roadmaps. The system offers the following advantages and capabilities: (1) Graphically portraying relationships between research and potential applications; (2) Helping accelerate science conversion by promoting champion interest in further research development; (3) Showing the node-link relationships of a project/capabilities/requirements network; (4) Treating nodes (projects/capabilities/requirements) as multi-valued (multi-attributed) quantities which are allowed to exist in many different research-requirement pathways simultaneously. This multiple perspectives capability provides a more accurate depiction of the multi-application nature of most research and technology, and the software enables the user to highlight just those specific node-link subnetworks of interest (the desired researchrequirement. pathways) without being overwhelmed by all possible node-links which constitute the larger network; (5) Promoting communications; (6) Identifying science and technology gaps; and (7) Identifying obstacles to rapid and low-cost technology development. 相似文献
297.
Ronald Weitzer 《Crime, Law and Social Change》2005,43(4-5):211-235
This article critically evaluates the theoretical and empirical literature on contemporary prostitution. Most research focuses
exclusively on street prostitution and female workers, with much less attention devoted to indoor prostitution, male and transgender
workers, customers, and managers. Drawing on the sparse literature available on these underexamined topics, the article demonstrates
how further research will yield a more nuanced and multifaceted understanding of contemporary prostitution. 相似文献
298.
Low self-control is at the heart of Gottfredson and Hirschi's (1990) general theory of crime and had been extensively investigated with the Grasmick, Tittle, Bursik, and Arneklev (1993) self-control scale. An advanced analytical tool, confirmatory techniques, had been recently applied to elucidate the underlying theoretical structure of the self-control construct. Most of these studies were limited, as they did not compare competing factorial measurement models. Furthermore, measures such as the Grasmick et al. scale had been used widely with diverse population groups and it was essential that the invariance of the measure be examined. The few studies that had performed this had addressed the invariance of the scale's factorial structure, but neglected to examine the invariance of the latent means structures. Testing the invariance of the latent means eliminates spurious results that may be artifacts of biased responding. The purpose of the current study was to investigate the structure of self-control by comparing three measurement models using confirmatory factor analysis and to explore the invariance of self-control across multiple groups from New Zealand. Two male groups were used: prison inmates and university students. The overall findings supported the Grasmick et al. scale as usefully represented by both a hierarchical order and a multidimensional structure. The measure was found to be generalizable across disparate groups, although differences in latent means were found between the two groups on the self-control dimensions. 相似文献
299.
Ronald T. Brown Steven L. Jaffe Jeffrey Silverstein Harry Magee 《Journal of youth and adolescence》1991,20(5):501-518
The effects of methylphenidate on hospitalized conduct-disordered (CD) adolescents were examined by using teacher ratings of behavior, a measure of classroom learning, and a test of impulsivity. Twenty-two male adolescents with CD, 12–18 years of age, participated in a double-blind, placebo-controlled, within-subject (crossover) design in which each adolescent received three doses of methylphenidate (10 mg, 15 mg, and 20 mg) and a placebo in a randomly assigned, counterbalanced order. Seven of the adolescents had a comorbid diagnosis of attention deficit hyperactivity disorder. Significant overall medication effects were shown on teacher ratings of conduct, and on number of arithmetic questions correctly completed and time spent. Within the limitations of this study, stimulant actions may be effective for some aspects of CD in the absence of attention deficit hyperactivity disorder, although only for specific measures.This project was supported by BRSG S 07 RR 05364 awarded to Ronald T. Brown by the Biomedical Research Support Grant Program, Division of Research Resources, National Institutes of Health, and by an award from the Emory University Research Fund.Portions of this paper were presented at the 96th annual meeting of the American Psychological Association, Atlanta, Georgia, August 1988.Received his Ph.D. from Georgia State University. His research include attention deficit disorders, psychopharmacology, and pediatric psychology.Received his M.D. from Albert Einstein School of Medicine. His research interests include adolescents and attention deficit disorder.Received his M.Ed. degree from Georgia State University. His research interests are in the area of attention deficit disorder.Received his M.D. from the University of West Virginia. His research interests include autism and attention deficit disorder. 相似文献
300.