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Declining profitability of agriculture and/or higher prices of forest products and services typically drive an increase in forest cover. This article examines changes in forest cover in Candelaria Loxicha, Mexico. Forest cover increased in the area as a result of coffee cultivation in coffee forest-garden systems. Dependence on forest products and services, and not prices of forest products, drive the process in our study site. Low international coffee prices and high labor demand outside the community might pull farmers out of agriculture, but they do not completely abandon the lands. A diversification in income sources prevents land abandonment and contributes to maintaining rural populations and coffee forest gardens. 相似文献
136.
Randy Gainey Mariel Alper Allison T. Chappell 《American Journal of Criminal Justice》2011,36(2):120-137
Fear of crime has long been considered a significant social problem, spurring decades of academic research and leading to
a variety of policy initiatives. Building on prior research, this study investigated the direct and indirect effects of demographic
characteristics, social and physical disorder, and prior victimization on fear of crime. Further, it assessed the direct and
indirect effects of perceived risk on fear. Finally, the research examined the extent to which social capital mediated the
impact of these variables on fear. Using data from a survey of residents in a southeastern city, analyses reveal that victimization
and disorder significantly predict fear of crime, and that risk perception and social capital mediate the relationship between
disorder and victimization on fear. Further, structural equation models show a number of interesting indirect effects. Policy
implications and directions for future research are discussed. 相似文献
137.
e-mail: spln{at}mail.rochester.edu Limited dependent variable (LDV) data are common in politicalscience, and political methodologists have given much good adviceon dealing with them. We review some methods for LDV "changepoint problems" and demonstrate the use of Bayesian approachesfor count, binary, and duration-type data. Our applicationsare drawn from American politics, Comparative politics, andInternational Political Economy. We discuss the tradeoffs bothphilosophically and computationally. We conclude with possibilitiesfor multiple change point work.
Author's note: This paper is a revised version of my "second-yearpaper" presented to the department in September 2005, and Ithank attendees for feedback. For comments on an earlier draft,I am grateful to Kevin Clarke, David Firth, Jeff Gill, KosukeImai, Tasos Kalandrakis, Andrew Martin, Kevin Quinn, Curt Signorino,Randy Stone, and two anonymous referees. Any remaining errorsand omissions remain mine and mine alone. 相似文献
138.
Arthur Spirling 《American journal of political science》2012,56(1):84-97
Native Americans are unique among domestic actors in that their relations with the U.S. government involve treaty making, with almost 600 such documents signed between the Revolutionary War and the turn of the twentieth century. We investigate the effect of constitutional changes to the treating process in 1871, by which Congress stripped the president of his ability to negotiate directly with tribes. We construct a comprehensive new data set by digitizing all of the treaties for systematic textual analysis. Employing scaling techniques validated with word‐use information, we show that a single dimension characterizes the treaties as more or less “harsh” in land and resource cession terms. We find that specific institutional changes to treaty‐making mechanisms had little effect on agreement outcomes. Rather, it is the relative bargaining power of the United States economically and militarily that contributes to worsening terms for Indians over the nineteenth century. 相似文献
139.
Lurie IS Berrier AL Casale JF Iio R Bozenko JS 《Forensic science international》2012,220(1-3):191-196
Methodology is presented for the profiling of fentanyl in seized drugs using ultra high performance liquid chromatography in combination with tandem mass spectrometry (UHPLC-MS/MS). Target analysis was performed for 40 fentanyl processing impurities, several of which are markers for a specific synthetic route (Siegfried or Janssen). For the separation of these solutes, an Acquity BEH C18 1.7 μm particle column (150 mm × 2.1 mm) with a binary 1% formic acid (pH 2.0)/acetonitrile gradient was used. For MS/MS detection, an atmospheric pressure positive electrospray source was employed with selected reaction monitoring (SRM). The coupling of the high separation power of UHPLC with the highly selective and sensitive detection of MS/MS is amenable to the determination of synthetic route and linking of drug seizures. The technology is also applicable to exhibits containing trace levels of fentanyl in the presence of significantly excess amounts of heroin and/or adulterants. 相似文献
140.
Molina DK Clarkson A Farley KL Farley NJ 《The American journal of forensic medicine and pathology》2012,33(4):344-348
ABSTRACT: It is essential that clinical physicians, medical personnel, medical examiners, and law enforcement agencies understand the types of injuries seen and demographics of children affected by intentional blunt force as this understanding can be crucial to the death and/or criminal investigations. An understanding of the injuries can also assist in drawing conclusions regarding how those injuries could have been sustained. This study discusses the types and patterns of injuries seen in blunt force homicides in children younger than 6 years. The study found that male infants are more often intentionally injured than are female infants and that fatal head injuries most frequently occur in the first year of life, whereas most fatal thoracoabdominal injuries occur in the first 3 years of life. In children with head injuries, subdural hemorrhage was the most common finding, followed by subarachnoid hemorrhage. In 2.5% of deaths due to head injury, concurrent neck injury was seen, a percentage far lower than previous literature would suggest if shaking was the primary mechanism of injury. Twelve legal confessions were also reviewed, none of which disclosed a pure mechanism of shaking the infant. 相似文献