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541.
目的通过对甲拌磷急性中毒致死大鼠脏器中乙酰胆碱(ACh E)、丁酰胆碱(BCh E)、对氧磷酶1(PON-1)和原癌基因蛋白(FOS)m RNA的表达研究,筛选出表达变化有统计学意义的脏器和中毒相关基因,探讨其在死亡原因推断中的价值。方法健康成年雌性SD大鼠,随机分为空白对照组和急性中毒死亡组,分别取心、肝、肺、脑和肠,提取总RNA,加入目的基因ACh E、BCh E、PON-1、FOS和内标基因β-肌动蛋白(β-actin)引物逆转录成c DNA后,利用实时荧光定量PCR技术(RT-PCR)检测各组c DNA的相对表达量的变化,并对各组结果进行统计学分析。结果肝脏中ACh E、BCh E和FOS m RNA的表达均上调(P0.05),ACh E m RNA在肺和脑中的表达均下调(P0.05)。结论肝脏和ACh E分别可以作为甲拌磷急性中毒致死的靶器官和基因表达标志,能为今后急性甲拌磷中毒的临床诊断与死亡推断提供依据。  相似文献   
542.
Scientific content analysis (SCAN) is a technique that claims to enable the detection of deception in written statements. The underlying assumption is that statements of self-experienced events differ in several ways – such as liveliness and concreteness – from imaginary statements. It is used in many countries as an investigative tool. Nevertheless, little research on the reliability and validity of the SCAN technique is available. In this paper, two studies are presented. The first study focuses on the accuracy of SCAN to detect deception by three groups of raters with a different level of experience. This study shows a lack of validity of SCAN. Study 2 investigated the inter-rater reliability as a possible explanation for the poor validity results, and found little agreement between raters in identifying SCAN criteria. Overall, results indicate that the psychometric qualities of SCAN as an investigative tool is insufficient for use in police practice.  相似文献   
543.
The present study validates a novel version of the Reaction time-based Concealed Information Test (RT-CIT) adapted for young children (7–10 years). Their ability to deny the possession of relevant information was related to individual differences in intelligence, processing speed, executive functioning and affective problems. The comparison between the knowledgeable group of children (N = 84) who took part in a mock surprise scenario and the unknowledgeable group (N = 78) indicated that by early school-age the RT-CIT can be considered a relatively reliable diagnostic tool for detecting concealed information. We found evidence indicating that executive functions are predictors of children's proficiency in concealing information; however, the specific interrelations were complex (children with lower inhibition and spatial working memory, but with better shifting performance were easier to detect as possessing concealed information). Finally, we found limited evidence for a substantial association between parent-reported emotional problems and children's proficiency in concealing information. This investigation has practical implications for the development of rigorous protocols to detect children's concealed knowledge within legal environments.  相似文献   
544.
When passively attending to suspects, observers are poor at distinguishing lies from truths. Deception research has therefore shifted to examining interview styles aimed at eliciting and enhancing deception cues. Based upon a literature review and three empirical studies, ten Brinke, L., Khambatta, P., and Carney, D. R. [2015. Physically scarce (vs. enriched) environments decrease the ability to successfully tell lies. Journal of Experimental Psychology: General, 144, 982–992. doi:10.1037/xge0000103] recommend increasing pressure on interviewees as it would increase lie detection accuracy. In this comment, we argue that these authors (1) misinterpret the literature when concluding that lie detection benefits from increasing pressure on interviewees, and (2) their data do not show that lie detection is more accurate when pressure is increased. In absence of such data, we recommend that increasing pressure on interviewees should be avoided: it hampers the elicitation of valuable information and can lead to false confessions.  相似文献   
545.
Urea nitrate (uronium nitrate, UN) is a powerful, improvised explosive that can be easily made from urea and nitric acid. It is considered the most frequently used, illegal explosive in the Israeli arena, which is responsible for the loss of more than a hundred lives in terrorist incidents. Urea nitrate is a colorless, crystalline substance that looks very much like sugar. A sensitive color test for UN was developed recently. It is based on the formation of a red dye in the reaction between p-dimethylaminocinnamaldehyde and UN under neutral conditions. A similar reaction with p-dimethylaminobezaldehyde produces a yellow dye. The two dyes have been synthesized, and their structures determined by X-ray crystallography. Both dyes are protonated Schiff bases, prevailing in the crystal in a quinoid form. They are identical to the compounds, which are obtained in the colorimetric detection of urea with the same reagents, under strong acidic conditions, whose structures have been postulated in the literature, but never fully proved experimentally.  相似文献   
546.
A video can be manipulated using synthetic zooming without using the state-of-the-art video forgeries. Synthetic zooming is performed by upscaling individual frames of a video with varying scale factors followed by cropping them to the original frame size. These manipulated frames resemble genuine natural (optical) camera zoomed frames and hence may be misclassified as a pristine video by video forgery detection algorithms. Even if such a video is classified as forged, forensic investigators may ignore the results, believing it as part of an optical camera zooming activity. Hence, this can be used as an anti-forensic method which eliminates digital evidence. In this paper, we propose a method for differentiating optical camera zooming from synthetic zooming for video tampering detection. The features used for this method are pixel variance correlation and sensor pattern noise. Experimental results on a dataset containing 3200 videos show the effectiveness of the proposed method.  相似文献   
547.
There is an increasing demand for automated verbal deception detection systems. We propose named entity recognition (NER; i.e., the automatic identification and extraction of information from text) to model three established theoretical principles: (i) truth tellers provide accounts that are richer in detail, (ii) contain more contextual references (specific persons, locations, and times), and (iii) deceivers tend to withhold potentially checkable information. We test whether NER captures these theoretical concepts and can automatically identify truthful versus deceptive hotel reviews. We extracted the proportion of named entities with two NER tools (spaCy and Stanford's NER) and compared the discriminative ability to a lexicon word count approach (LIWC) and a measure of sentence specificity (speciteller). Named entities discriminated truthful from deceptive hotel reviews above chance level, and outperformed the lexicon approach and sentence specificity. This investigation suggests that named entities may be a useful addition to existing automated verbal deception detection approaches.  相似文献   
548.
Nowadays, surveillance systems are used to control crimes. Therefore, the authenticity of digital video increases the accuracy of deciding to admit the digital video as legal evidence or not. Inter‐frame duplication forgery is the most common type of video forgery methods. However, many existing methods have been proposed for detecting this type of forgery and these methods require high computational time and impractical. In this study, we propose an efficient inter‐frame duplication detection algorithm based on standard deviation of residual frames. Standard deviation of residual frame is applied to select some frames and ignore others, which represent a static scene. Then, the entropy of discrete cosine transform coefficients is calculated for each selected residual frame to represent its discriminating feature. Duplicated frames are then detected exactly using subsequence feature analysis. The experimental results demonstrated that the proposed method is effective to identify inter‐frame duplication forgery with localization and acceptable running time.  相似文献   
549.
550.
Environmental surface sampling is crucial in determining the zones of contamination and overall threat assessment. Viability retention of sampled material is central to such assessments. A systematic study was completed to determine viability of vegetative cells under nonpermissive storage conditions. Despite major gains in nucleic acid sequencing technologies, initial positive identification of threats must be made through direct culture of the sampled material using classical microbiological methods. Solutions have been developed to preserve the viability of pathogens contained within clinical samples, but many have not been examined for their ability to preserve biological agents. The purpose of this study was to systematically examine existing preservation materials that can retain the viability of Bacillus anthracis vegetative cells stored under nonpermissive temperatures. The results show effectiveness of five of seventeen solutions, which are capable of retaining viability of a sporulation deficient strain of B. anthracis Sterne when stored under nonrefrigerated conditions.  相似文献   
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