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991.
992.
A custom-built ion mobility spectrometer has been used to obtain the IMS spectra of cocaine, heroin, amphetamine sulfate and LSD at different drug concentrations and desorption temperatures. Practical detection limits for these four drugs were obtained as a function of desorber temperature and for heroin as a function of analysis time. Spectral and ionization interferences for each of the four drugs of interest were determined. Spectral interferences by innocuous materials are few; ionization interferences occur only at very high ratios of the mass of innocuous material to that of the drug of interest. 相似文献
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Hédouin V Bourel B Martin-Bouyer L Bécart A Tournel G Deveaux M Gosset D 《Journal of forensic sciences》1999,44(2):351-353
This study concerns the determination of morphine concentrations in fly larvae reared on rabbits administered different concentrations of morphine and a correlation between concentrations of the drug in larvae and tissues. Three rabbits (R1, R2 and R3) were given dosages of 12.5, 25.0 and 50.0 mg/h of morphine over a 3 h period via continuous ear artery perfusion. These dosages and time of perfusion were calculated to create tissue concentrations of morphine similar to those encountered in human death due to overdose. Morphine blood level plateau was attained after 1 h of perfusion. A fourth rabbit was used as a control. To evaluate drug concentrations, tissues were sampled using a coelioscopic technique. Approximately 400 eggs of Lucilia sericata, all of the same age category, were placed in eyes, nostrils and mouth of each rabbit carcass. Larvae and puparia were regularly collected from each rabbit for toxicological analysis. The concentrations of the drug in the tissues sampled were determined to be similar to those normally encountered in human overdoses and were correlated with the dosage of morphine that had been administered. Morphine was detected in all larvae and pupae fed on tissues from carcasses administered morphine, except for puparia from the colony fed on the R1 animal which received 12.5 mg/h dosage of morphine. All samples from the control rabbit were negative for morphine. Concentrations of morphine in larvae reared on rabbit carcasses containing morphine were 30 to 100 times lower than the concentrations found in the tissues. A correlation between the tissue concentrations and larval concentrations was found in only 3rd instar larvae (80 to 140 h following hatching). No correlations were found between administered dosages, tissue concentrations and younger larvae, prepuparial larvae or puparia. 相似文献
998.
Is local politics local? French evidence 总被引:2,自引:0,他引:2
Abstract. In advanced democracies, are local political decisions determined by local events? Or are they really shaped by national forces? For the United States case, the evidence on this question is mixed. For the French case, the focus here, the evidence is also mixed, but less hard. In fact, for cantonal elections, in many ways archtypical local affairs, relevant systematic findings are virtually absent. We ask whether the cantonal elections of the Fifth Republic can be better understood as national, rather than local, contests. Our analysis leads us to the conclusion that the basic answer is, ‘yes’. There appear several theoretical reasons for this, which we give an account of. Further, we go on to show that cantonal races can actually serve as barometers to forecast upcoming national races. 相似文献
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L'Honorable Jean Chrtien 《Canadian public administration. Administration publique du Canada》1976,19(1):112-120
Sommaire. L'un des principaux problèmes dans notre société dans les années à venir est celui des relations entre le gouvernement et les citoyens. Cette question est l'une des plus importantes au moment où on s'interroge de plus en plus sur le rôle des grandes institutions publiques et privées. L'un des moyens par lequel le gouvernement peut devenir plus souple et plus sensibiliséà certains besoins et à certains problèmes est par la décentralisation. Ceci implique premièrement le déplacement d'unités et de functions du gouvernement fédéral situées dans la Région de la Capitale nationale et dans d'autres centres urbains importants vers d'autres régions du pays; et, deuxièmement, l'attribution de plus d'autorité aux agents qui travaillent à l'extérieur de la Région de la Capitale nationale. La décentralisation physique peut aider l'unité nationale en assurant la présence du gouvernement fédéral dans toutes les régions du pays; elle peut aider l'expansion économique régionale par le déplacement judicieux d'opérations gouvernementales dans des régions moins avantagées du pays; elle peut contribuer à une croissance urbaine équilibrée en aidant le développement des communautés plus petites. La décentralisation d'autorité met l'accent sur la souplesse et l'efficacité de la réalisation des programmes et de la formulation des politiques. L'application d'une politique de décentralisation doit se faire dans le cadre de certaines contraintes. II est nécessaire de maintenir l'uniformité, à l'échelle nationale, d'un grand nombre de politiques et de programmes et il faut assurer que l'autorité ministérielle ne soit pas diluée; il est nécessaire d'assurer la responsabilité des programmes dont les objectifs et les critères de réussite ne sont pas faciles à quantifier; il faut maintenir l'efficacité opérationnelle d'une unité; et il faut assurer un traitement équitable pour les employés et leurs families. Abstract. One of the major issues which must be addressed in the years to come is that of the relationship between government and citizens. This is especially important at a time when the role of large organizations, whether public or private, is coming under increasing scrutiny. Decentralization is a means of increasing the sensitivity and responsiveness of big government. Decentralization involves both the relocation of federal government units and functions from the National Capital Region and other major urban centres towards other areas of the country and the delegation of more authority from headquarters to officers in the field. Physical decentralization can contribute to national unity by an increased federal presence throughout the country; it can contribute to regional economic expansion by the judicious location of units in disadvantaged areas; it can contribute to improved demographic patterns by setting precedents for relocation from major urban centres. Decentralization of authority can enhance the sensitivity and over-all effectiveness of both program delivery and policy formulation. The constraints on decentralization include the need to retain national consistency of many policies and programs, the need to ensure that ministerial influence is not diluted, the need to ensure accountability in programs in which the objectives and criteria for success are not easily quantifiable, the need to ensure the maintenance of operating effectiveness of a unit, and the need to ensure equitable and humane treatment of employees and their families involved in relocation. 相似文献