首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   11681篇
  免费   1189篇
各国政治   413篇
工人农民   376篇
世界政治   839篇
外交国际关系   282篇
法律   8993篇
中国共产党   1篇
中国政治   82篇
政治理论   1811篇
综合类   73篇
  2020年   338篇
  2019年   340篇
  2018年   386篇
  2017年   446篇
  2016年   461篇
  2015年   428篇
  2014年   418篇
  2013年   1167篇
  2012年   268篇
  2011年   358篇
  2010年   531篇
  2009年   485篇
  2008年   276篇
  2007年   246篇
  2006年   355篇
  2005年   239篇
  2004年   228篇
  2003年   224篇
  2002年   201篇
  2001年   439篇
  2000年   346篇
  1999年   296篇
  1998年   143篇
  1997年   129篇
  1996年   104篇
  1995年   131篇
  1994年   141篇
  1993年   115篇
  1992年   216篇
  1991年   235篇
  1990年   218篇
  1989年   230篇
  1988年   208篇
  1987年   178篇
  1986年   207篇
  1985年   226篇
  1984年   220篇
  1983年   185篇
  1982年   147篇
  1981年   131篇
  1980年   129篇
  1979年   150篇
  1978年   92篇
  1977年   79篇
  1976年   67篇
  1975年   71篇
  1974年   77篇
  1973年   64篇
  1972年   55篇
  1971年   56篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Riots are extreme events, and much of the early research on rioting suggested that the decision making of rioters was far from rational and could only be understood from the perspective of a collective mind. In the current study, we derive and test a set of expectations regarding rioter spatial decision making developed from theories originally intended to explain patterns of urban crime when law and order prevail—crime pattern and social disorganization theory—and consider theories of collective behavior and contagion. To do this, we use data for all riot‐related incidents that occurred in London in August 2011 that were detected by the police. Unlike most studies of victimization, we use a random utility model to examine simultaneously how the features of the destinations selected by rioters, the origins of their journeys, and the characteristics of the offenders influence offender spatial decision making. The results demonstrate that rioter target choices were far from random and provide support for all three types of theory, but for crime pattern theory in particular. For example, rioters were more likely to engage in the disorder close to their home location and to select areas that contained routine activity nodes and transport hubs, and they were less likely to cross the Thames River. In terms of contagion, rioters were found to be more likely to target areas that had experienced rioting in the previous 24 hours. From a policy perspective, the findings provide insight into the types of areas that may be most vulnerable during riots and why this is the case, and when particular areas are likely to be at an elevated risk of this type of disorder.  相似文献   
992.
MARK D. RAMIREZ 《犯罪学》2013,51(2):329-364
Scholarship has long noted the importance of understanding the changes that occur over time in aggregate public support for punitive criminal justice policies. Yet, the lack of a reliable and valid measure of this concept limits our understanding of this aspect of the criminal justice system. This research develops a measure of public support for punitive policies from 1951 to 2006 using 242 administrations of 24 unique survey indicators. It argues that punitive sentiment is politically constructed via frames focusing on the permissiveness of the criminal justice system. Punitive sentiment is estimated with an error‐correction model showing both the short‐ and long‐term relationships between punitive sentiment and presidential framing of crime, public dissatisfaction with social welfare policies, and perceptions of racial integration. The results highlight the complex dynamics responsible for the change over time in punitive sentiment as well as the possibilities of obtaining public support for alternative solutions to crime.  相似文献   
993.
This research explains the temporal clustering of hate crimes. It is hypothesized that many hate crimes are retaliatory in nature and tend to increase, sometimes dramatically, in the aftermath of an antecedent event that results in one group harboring a grievance against another. Three types of events are used to test and refine the argument: 1) contentious criminal trials involving interracial crimes, 2) lethal terrorist attacks, and 3) appellate court decisions concerning same‐sex marriage. The results from time‐series analyses indicate that contentious trial verdicts and lethal domestic terrorist attacks precede spikes in racially or religiously motivated hate crimes, whereas less evidence is found for antigay hate crimes after appellate court rulings that grant rights to same‐sex partners. The model put forth in this article complements prior work by explaining in part the timing of hate crime clusters.  相似文献   
994.
Forensic arthropod succession patterns are known to vary between regions. However, the northern habitats of the globe have been largely left unstudied. Three pig carcasses were studied outdoors in Whitehorse, Yukon Territory. Adult and immature insects were collected for identification and comparison. The dominant Diptera and Coleoptera species at all carcasses were Protophormia terraneovae (R‐D) (Fam: Calliphoridae) and Thanatophilus lapponicus (Herbst) (Fam: Silphidae), respectively. Rate of decomposition, patterns of Diptera and Coleoptera succession, and species dominance were shown to differ from previous studies in temperate regions, particularly as P. terraenovae showed complete dominance among blowfly species. Rate of decomposition through the first four stages was generally slow, and the last stage of decomposition was not observed at any carcass due to time constraints. It is concluded that biogeoclimatic range has a significant effect on insect presence and rate of decomposition, making it an important factor to consider when calculating a postmortem interval.  相似文献   
995.
The use of narrow‐banded visible light sources in improving the visibility of injuries has been hardly investigated, and studies examining the extent of this improvement are lacking. In this study, narrow‐banded beams of light within the visible light spectrum were used to explore their ability in improving the visibility of external injuries. The beams of light were induced by four crime‐lites® providing narrow‐banded beams of light between 400 and 550 nm. The visibility of the injuries was assessed through specific long‐pass filters supplied with the set of crime‐lites®. Forty‐three percent of the examined injuries improved in visibility by using the narrow‐banded visible light. In addition, injuries were visualized that were not visible or just barely visible to the naked eye. The improvements in visibility were particularly marked with the use of crime‐lites® “violet” and “blue” covering the spectrum between 400–430 and 430–470 nm. The simple noninvasive method showed a great potential contribution in injury examination.  相似文献   
996.
Locating exactly where trace explosive residue samples should be sought during sample collection at bomb scenes is not specified in the published literature or guidelines; in this area, it is generally acknowledged that forensic practices are based on tradition rather than evidence. This study investigated patterns in the spatial distribution of postblast 1,3,5‐trinitro‐1,3,5‐triazocyclohexane residue from a series of unconfined detonations, over a range of sampling sites, and at two different detonation heights. The amount of residue recovered from the sites decreased as a function of distance from the center of the explosion. [Correction added after online publication 27 December 2012: In the preceding sentence, “increased” was corrected to “decreased” to agree with the conclusion of the article.] As the height of the detonations increased, more residues were found from all sampling sites. The findings of this empirical study have a number of important practical implications including determining where residue samples are best sought at crime scenes.  相似文献   
997.
The authors report an unusual case of suicide of an anesthesiologist, in which the suicide manner and means depend upon the victim's occupation. This is the first case report published in Italy of a death involving propofol and other drugs. The anesthesiologist was found dead with an empty drip still inserted in the hand and another one near his body. Forensic and toxicological findings suggested that the cause of death was a respiratory depression due to a self‐administration of a rapidly infused lethal drug mixture. Analytical drug quantification was performed by gas chromatography‐mass spectrometry. Blood analysis revealed: zolpidem (0.86 μg/mL), propofol (0.30 μg/mL), midazolam (0.08 μg/mL), thiopental (0.03 μg/mL), and amitriptyline (0.07 μg/mL). Adipose tissue and hair analysis suggested a previous and repeated use of these drugs verifying the fact that in Italy recreational abuse of anesthetic and sedative agents in health care practitioners is becoming an increasing problem.  相似文献   
998.
The foot measurements are important in forensic field as they can be used as body height predictors for an individual. The morphology of human feet shows the variations and therefore the aim of this study was to find the relation between stature and foot measurements and to generate population‐specific equations. We measured the stature and bilateral foot measurements of 71 volunteers ranging in age between 18 and 27 years using standard measurements technique. The results revealed nonsignificant bilateral differences in all sex groups (< 0.05). Sex differences were found to be significant in all foot measurements (< 0.001). The highest significant and positive correlation coefficients with stature were observed for foot length in males (r = 0.759), in females (r = 0.722), and in the sex‐mixed group (r = 0.865). According to the nonsignificant sex effects on the relation between stature and foot dimensions, the regression equations were computed only for the pooled mixed‐sex group. Our study provides equations that can help to estimate stature from foot measurements among Slovaks.  相似文献   
999.
Fibers are a commonly encountered evidence type and fiber comparisons are routinely conducted. When the characteristics of questioned and known fibers correspond, the probative value is limited because the characteristics compared are determined by their manufacture. It would be valuable to test the hypothesis that questioned fibers originated from a specific carpet. One means of testing this is to analyze fine particles on the fibers. A procedure was developed for removing adhering particles from fibers and preparing them for scanning electron microscopy/ energy dispersive X‐ray spectrometry (SEM/EDS) analysis. The efficacy of several fluids (acetone, ethanol, hexanes, aqueous ethanol, aqueous sodium hexametaphosphate) and agitation methods (sonication and vortexing) for removing particles from fibers was evaluated. The most effective method evaluated was sonication in ethanol for 10 min. The recovered particles were filtered onto a polycarbonate filter and analyzed by automated SEM/EDS analysis to generate data on the particle assemblage. This method makes possible future research to test the within‐item and between‐item variability of particle assemblages on fibers.  相似文献   
1000.
Comparative analyses of 50 single‐layer white architectural paints were conducted to determine the discrimination power using standard techniques and to provide a basis for assessing significance when paints with limited features are not discriminated. Utilizing Fourier transform infrared spectroscopy (FTIR), 68 undifferentiated pairs resulted, yielding a discrimination of 94.45%. Adding stereomicroscopy, scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS) and backscatter electron (BSE) imaging, and pyrolysis‐gas chromatography/mass spectrometry (Py‐GC/MS), the overall discrimination was 99.35%. The study included blind verification replicates, which resulted in the only pairs without indications of physical or chemical differences. The remaining groups of undifferentiated samples contained subtle differences by at least one technique, but were considered undifferentiated for the discrimination power evaluations. This study demonstrates a high degree of discrimination of single‐layer white architectural paints using methods of analysis often encountered in forensic science laboratories.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号