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11.
An important component of crime scene reconstruction is bloodstain pattern analysis (BPA). Where BPA concerns impact patterns, estimating the area of origin is critical information for scene reconstruction. Traditionally, this is achieved by measuring individual bloodstains and performing trigonometric calculations; however, 3D scanning has been proposed as a viable alternative for overcoming logistical and practical concerns with the manual method. Therefore, this project aimed to establish whether the FARO Focus 3D scanner and FARO Zone 3D software can improve the accuracy of area of origin estimates relative to the manual method. We created a series of eight bloodstain impact patterns and performed paired analysis using the two methods to estimate areas of origin for each pattern. Our data suggested that FARO-derived estimates were generally more accurate than using the manual method. FARO-estimated heights of origin areas were generally closer to the true distance. Both methods underestimated the distance from the wall for most patterns originating 150mm or greater from the wall, but overestimated distances for patterns originating closer to the wall. The degree to which distances were underestimated increased significantly the further the blood source was from the wall and was greater for FARO-derived estimates. The results of this research contribute to the validation of these instruments for operational implementation for BPA and should be considered alongside the practical benefits of 3D scanning relative to manual methods. Further, 3D scanning can provide reliable BPA reconstruction documentation for technical review and court presentation.  相似文献   
12.
Minutiae are small distinguishing features found along every ridge flow, which make each friction ridge print unique. The most common friction ridge prints found at the crime scene are fingerprints; therefore, the most of the minutiae studies are focused exactly on this kind of prints. The authors believe that further examination and enlargement of the palm print database could result in better use of the palm prints for personal identification. We analyzed a total of 160 palm prints from 40 females and 40 males aged between 18 and 70 years from Slovakia. For the evaluation of the minutiae, the area of the hypothenar had to be marked out. The classification of the minutiae used for this study was based on a modified version of the classification system using the total of 13 types of minutiae. The frequency of every minutiae type was calculated and, using the chi-square test with Yates's correction, bilateral and sex differences were assessed. The relationship between the different types of minutiae was examined with Pearson's correlation test. During the initial phases of the identification process, the focus should be on the least common types of minutiae (Y or M and return), which were found not to correlate; thus, their mutual occurrence is random (e.g., overlap—Y or M, crossbar—return, or Y or M—dock). The results of the present study show which specific minutiae types are the most suitable for personal identification. These findings may be beneficial in more effective outcome of the identification process.  相似文献   
13.
Novel psychoactive substances (NPS) are synthetic drugs that pose serious public health and safety concerns. A multitude of NPS have been identified in the United States, often implicated in forensic investigations. The most common and effective manner for identifying NPS is by use of mass spectrometry and the true utility lies within nontargeted acquisition techniques. During this study, a liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) assay was developed, validated, and implemented for forensic toxicology testing. A SCIEX TripleTOF™ 5600 + with SWATH® acquisition was used. Resulting data were compared against an extensive library database containing more than 800 compounds. The LC-QTOF-MS assay was applied to the reanalysis of biological sample extracts to discover emergent NPS. More than 3,000 sample extracts were analyzed, and more than 20 emerging NPS were detected for the first time. Among these were isopropyl-U-47700, 3,4-methylenedioxy-U-47700, fluorofuranylfentanyl, N-methyl norfentanyl, 2F-deschloroketamine, 3,4-methylenedioxy-alpha-PHP, eutylone, and N-ethyl hexedrone.  相似文献   
14.
A simple, quick, selective, sensitive, and effective field-friendly method capable of being used by nonexperts has been developed for detecting mitragynine in Mitragyna speciosa (kratom) using surface-enhanced Raman spectroscopy (SERS). Over 100 samples and blanks (known to be either positive or negative for the presence of mitragynine) were examined in duplicate using five identical handheld Raman spectrometers, which provided a data set of over 1,000 examinations. Based on the results of these analyses, the method yielded a true-positive rate of 99.3%, a true-negative rate of 97.9%, a false-positive rate of 2.1%, and a false-negative rate of 0.7%. The average minimum detectable concentration (Cm) of mitragynine that reproducibly yielded a match for one of the library spectra on all five instruments was determined to be 342 ng/mL (ppb). This Cm value is a conservative estimate considering that the extraction process was not fully optimized by this study, which was not necessary since the Cm value achieved was well below typical mitragynine concentrations in kratom (1.3–2.3%). The method is ideal (i) for prioritizing samples for additional testing using other more time-consuming laboratory-based techniques needed to detect and quantify mitragynine and (ii) for field use at international mail facility (IMF) satellite laboratories to help interdict kratom and prevent this dangerous product from reaching the U.S. supply chain.  相似文献   
15.
Following 9/11, Al-Qaeda-orchestrated plots were considered the greatest threat to Western security and sparked the coalition’s war on terror. Close to a decade later, the post-9/11 threat landscape had shifted significantly, leading then CIA-director Leon Panetta to describe “the lone-wolf strategy” as the main threat to the United States. Subsequent lone-actor attacks across the West, including the cities of London, Nice, Berlin, Stockholm, Ottawa and Charleston, further entrenched perspectives of a transformed security landscape in the “after, after-9/11” world. The unique features of lone-actor terrorism, including the challenges of interdiction and potential of copycat attacks, mean that the media is likely to play a particularly important role in shaping the reactions of the public, affected communities and copycat attackers. This article presents findings from a content analysis of British and Danish newspaper reporting of lone-actor terrorism between January 2010 and February 2015. The study highlights that lone-actor terrorism is framed, with national variations, as a significant and increasing problem in both countries; that Islamist lone-actors are often represented as distinct from far-right lone-actors; and that some reporting, despite relatively limited amplification of specific terrorist messages, potentially aids lone-actors by detailing state vulnerabilities to attacks.  相似文献   
16.
ABSTRACT

Recently, “problem-solving” courts have been developed as an alternative to imprisonment. They are often called “specialty” courts because they process and divert into treatment programs offenders who are seen as different from the general criminal population, such as those with mental health or drug problems, those who are homeless or veterans, and those who engage in domestic violence. Based on a 2017 national survey of 1,000 respondents, the current study examines overall public support for rehabilitation as a goal of corrections and then focuses specifically on support for different types of specialty courts. The analysis reveals that the American public endorses not only the rehabilitative ideal but also the use of problem-solving courts. Further, with only minimal variation, strong support for these courts appears to exist regardless of political orientation and sociodemographic characteristics.  相似文献   
17.

Young adulthood represents a developmental period with disproportionately heightened risk of losing a job. Young adult unemployment has been linked to increased mental health problems, at least in the short term. However, their possible long-term impacts, often referred as “scarring effects,” have been understudied, possibly underestimating the magnitude of mental health burden that young adult unemployment generates. This longitudinal study examined whether duration of unemployment during young adulthood is associated with later mental health disorders, after accounting for mental and behavioral health problems in childhood. Furthermore, the current study investigated whether childhood neighborhood characteristics affect this association and if so, in what specific functional ways. Data were drawn from a longitudinal study of developmental outcomes in a community sample in Seattle. Data collection began in 1985 when study participants were elementary students and involved yearly assessments in childhood and adolescence (ages 10–16) and then biennial or triennial assessments (ages 18–39; N?=?677 at age 39; 47% European American, 26% African American, 22% Asian American, and 5% Native American; 49% female). The current study findings suggest that duration of unemployment across young adulthood increased mental health problems at age 39, regardless of gender. Childhood neighborhood characteristics, particularly their positive aspect, exerted independent impacts on adult mental health problems beyond unemployment experiences across young adulthood. The current findings indicate a needed shift in service profiles for unemployed young adults—a comprehensive approach that not only facilitates reemployment but also addresses mental health needs to help them to cope with job loss. Further, the present study findings suggest that childhood neighborhoods, particularly positive features such as positive neighborhood involvement, may represent concrete and malleable prevention targets that can curb mental health problems early in life.

  相似文献   
18.
Abstract

What is ‘relational theorizing’ in International Relations and what can it offer? This article introduces a thematic section that responds to these questions by showing two things. First, relational theorizing is not a doctrine or a method, but a set of analyses that begin with relations rather than the putative essences of constitutively autonomous actors. Second, relational theorizing has emerged from different geo-linguistic traditions, and a relational approach to International Relations (IR) can offer the language and space for increased and productive engagement beyond Anglophone scholarship. This thematic section takes a significant step in this direction by staging a dialogue between Sinophone and Anglophone scholarship on relational IR theorizing. Such an engagement shows points of comparison and contrast, convergence and divergence. In this way, the essays presented here contribute to developing a more ‘global’ IR.  相似文献   
19.
Governments are increasingly implementing smart and digital approaches to promoting citizen participation. However, whether online participation platforms are tools that improve inclusivity in citizen participation remains underexplored. To address this gap, this article focuses on the role of recruitment messages and their effect on participation in an online participation platform by gender and age. A field experiment with a neighborhood census sample (N = 6,066) shows that online participation dips for younger and older citizens and is equal among women and men. For the age groups between 60 and 75, differences in the control and intervention recruitment messages significantly impacted participation. These findings can help public managers tailor recruitment strategies to facilitate inclusive participation and represent a first step toward learning what types of messages are effective for whom.  相似文献   
20.
The optical and morphological properties of resveratrol were investigated. This nontoxic fluorescent natural material, emitting in the visible blue light, was used as an optical marker, enabling the enhancement of the image contrast coming from relief pictures marked on challenging surfaces. By applying appropriated imaging softwares, this marker was verified to be very useful in the latent fingerprint recognition deposited on different wood surface types, mainly those with high level of roughness, where conventional forensic materials do not allow effective fingerprint image visualization.  相似文献   
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