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The development of methodologies using inexpensive, fast, and reliable instrumention is desirable in illicit drug analysis. The purpose of this study was based on cyclic voltammetry technique to differentiate the electrochemical behavior of ?9‐THC, the psychoactive substance in marijuana, and five different extract plants to yield false positive results after analysis protocol for cannabinoids using thin‐layer chromatography and Fast Blue B salt. After applying a deposition potential of ?0.5 V in a glassy carbon working electrode, the results indicated an anodic peak current at 0.0 V versus Ag/AgCl after addition of ?9‐THC solution in the electrochemical cell, and limits of detection and quantification were 1.0 ng mL?1 and 3.5 ng mL?1, respectively. Other interfering plants showed distinct amperometric responses. This methodology was useful to detect ?9‐THC even in the presence of the Fast Blue B salt, which avoided false positive results for all the studied extract plants.  相似文献   
194.
Lesions of the digestive tract due to barotrauma resulting from compressed air application are not common, are rarely lethal, and largely affect the sigmoid and descending colon. Moreover, their pathogenic mechanism is a topic of discussion because these lesions have multiple characteristics. Here, the authors describe an autoptic case of death from lesions of the ascending and transverse segments, with perforations and bleeding suffusions as well as ischemic areas covered the colonic wall that was extremely thinned, congested, and hemorrhagic, with considerable flattening leading to disappearance of the mucosal folds and with numerous petechial hemorrhages. The pathological framework of lung congestion made it possible to identify the mechanism responsible for this death as depletion of the heart's pumping function, which contributed significantly to the acute respiratory failure due to respiratory distress as well as to reduced mobility of the diaphragm due to intestinal distension. Acute heart failure played an important role in this death.  相似文献   
195.
Previous research has revealed a strong association between moral disengagement (MD) and criminal behaviour. However, few studies have attempted to examine the contribution of dark personalities to MD. This study aims to first analyse the differences between forensic and community samples in the use of MD strategies and then replicate the factorial structure of the Dark Triad Dirty Dozen scale in an incarcerated sample as a pre-condition to examine the relationship between dark triad (DT) traits (i.e. Machiavellianism, psychopathy and narcissism) and MD. The sample comprised 160 incarcerated and 160 community adults. Comparisons between these two groups demonstrate that the incarcerated sample scored higher in MD and DT than the community sample. Furthermore, different MD strategies were related to each of the DT traits in the forensic and community samples. The results of exploratory factor analysis for the incarcerated sample indicate adequate fit indices for a bifactorial model of the DT (a latent factor of the shared variance of these constructs named the global DT and three specific latent factors for each component of the DT). The SEM analysis for this bifactorial model and MD disclosed direct and significant relationships between the global DT and MD in the incarcerated adults, while the Machiavellianism factor was directly and significantly related to MD in the community adults. These results highlight the relevance of cognitive (i.e. MD) strategies in forensic contexts, especially in incarcerated adults who present high levels of this DT profile.  相似文献   
196.
Craniofacial superimposition is a technique potentially useful for the identification of unidentified human remains if a photo of the missing person is available. We have tested the reliability of the 2D‐3D computer‐aided nonautomatic superimposition techniques. Three‐dimension laser scans of five skulls and ten photographs were overlaid with an imaging software. The resulting superimpositions were evaluated using three methods: craniofacial landmarks, morphological features, and a combination of the two. A 3D model of each skull without its mandible was tested for superimposition; we also evaluated whether separating skulls by sex would increase correct identifications. Results show that the landmark method employing the entire skull is the more reliable one (5/5 correct identifications, 40% false positives [FP]), regardless of sex. However, the persistence of a high percentage of FP in all the methods evaluated indicates that these methods are unreliable for positive identification although the landmark‐only method could be useful for exclusion.  相似文献   
197.
The Middle East is one of the world regions that has frequently suffered from armed conflicts that resulted in mass burials. However, the detection of clandestine graves in such an arid environment by deploying remote sensing payload on unmanned aerial vehicles (UAVs) has received little attention. The present study used a UAV equipped with a thermal sensor aimed at narrowing down the search area of possible gravesites in the arid climate of Kuwait. The enclosed research area, which includes both control and experimental mass graves, was imaged for 18 months. The variation in topsoil temperature and soil moisture between the graves and their surroundings was evaluated. The results of the analysis demonstrated the effectiveness of thermal imaging techniques in detecting heat produced from buried sheep carcasses and detecting the change in grave soil moisture for our research environment for 7 and 10 months, respectively. The buried animals significantly influenced the topsoil temperature (p = 0.044), while the height from which the images were captured had an insignificant effect on the measured temperature within the range tested (p = 0.985). Furthermore, there was a negative correlation (−0.359) between grave temperature and the calculated soil moisture. The results from these cost- and time-effective search methods presented in this study confirm their potential for the detection of burial sites in an arid environment.  相似文献   
198.
Fentanyl, fentanyl analogs, and other novel synthetic opioids (NSO), including nitazene analogs, prevail in forensic toxicology casework. Analytical methods for identifying these drugs in biological specimens need to be robust, sensitive, and specific. Isomers, new analogs, and slight differences in structural modifications necessitate the use of high-resolution mass spectrometry (HRMS), especially as a non-targeted screening method designed to detect newly emerging drugs. Traditional forensic toxicology workflows, such as immunoassay and gas chromatography mass spectrometry (GC–MS), are generally not sensitive enough for detection of NSOs due to observed low (sub-μg/L) concentrations. For this review, the authors tabulated, reviewed, and summarized analytical methods from 2010–2022 for screening and quantification of fentanyl analogs and other NSOs in biological specimens using a variety of different instruments and sample preparation approaches. Limits of detection or quantification for 105 methods were included and compared to published standards and guidelines for suggested scope and sensitivity in forensic toxicology casework. Methods were summarized by instrument for screening and quantitative methods for fentanyl analogs and for nitazenes and other NSO. Toxicological testing for fentanyl analogs and NSOs is increasingly and most commonly being conducted using a variety of liquid chromatography mass spectrometry (LC–MS)-based techniques. Most of the recent analytical methods reviewed exhibited limits of detection well below 1 μg/L to detect low concentrations of increasingly potent drugs. In addition, it was observed that most newly developed methods are now using smaller sample volumes which is achievable due to the sensitivity increase gained by new technology and new instrumentation.  相似文献   
199.
Forensic science professionals are routinely exposed to potentially traumatizing evidence. This study aimed to estimate the prevalence of occupational posttraumatic stress disorder (PTSD) among forensic science professionals, identify job-related correlates of PTSD symptoms, and examine the role of social support in mitigating PTSD symptomology. In response to recruitment through the American Academy of Forensic Sciences, the American Society of Crime Laboratory Directors, and Evidence Technology Magazine, 449 forensic science professionals participated in the current study. Results found that 73.5% (n = 330) of the overall sample experienced at least one work-related traumatic event consistent with meeting Criterion A for PTSD, and these rates were higher for field-based respondents (n = 203, 87.9%). The prevalence of past-month provisional PTSD was 21.6% for the full sample. Disaggregated PTSD rates were 29.0% and 14.5% for field-based and non-field-based respondents, respectively. These rates were 6- to 8-fold higher than the past-year prevalence of PTSD in the general US population, estimated to be 3.5%, and were found to be at least as high as those observed in prior epidemiological research with non-treatment seeking members of the US military deployed to war zones in Iraq and Afghanistan. Results further showed that social support was protective against PTSD symptomology. The high rates of occupational exposure to trauma and consequent PTSD symptomology observed in this large sample of forensic science professionals highlight the under-acknowledged psychological risks of these occupations and the need for enhanced attention to mental health resources for these professionals.  相似文献   
200.
In the absence of surface indications of burial sites, law enforcement or humanitarian organizations are faced with the difficult task of focusing large-scale ground searches to a manageable excavation area. A geoforensic-based survey may exclude parts of the landscape for reasons such as diggability or viewshed analysis but leave areas still too large for invasive exploration. This work examines how drone-based remote sensing, geophysics, and search dogs may be combined to narrow such searches. Here, we ask the reader to consider two examples where forensic geomorphology and land use provided a range of possible burial locations. Following this is a multi-proxy approach to similar dilemma, with a search-to-scene case study using remote sensing (drone photography), geophysics, ground probes, and search dogs. This approach is not presented as a definitive guide, but serves as an example of the conjunctive use of well-studied methods to approach a common problem in geoforensics.  相似文献   
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