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:从到   被引次数:从到   他引次数:从到 提示：输入*表示无穷大
全文获取类型
  收费全文   317篇
  免费   2篇
专业分类
各国政治   28篇
工人农民   5篇
世界政治   3篇
法律   258篇
中国政治   12篇
政治理论   12篇
综合类   1篇
出版年
  2024年   39篇
  2023年   151篇
  2021年   36篇
  2020年   3篇
  2017年   2篇
  2016年   1篇
  2015年   3篇
  2013年   21篇
  2012年   8篇
  2011年   8篇
  2010年   11篇
  2009年   10篇
  2008年   5篇
  2007年   1篇
  2006年   4篇
  2005年   1篇
  2004年   3篇
  2001年   1篇
  2000年   2篇
  1998年   1篇
  1997年   2篇
  1991年   3篇
  1989年   1篇
  1984年   1篇
  1983年   1篇
排序方式： 共有319条查询结果，搜索用时 0 毫秒
211.
    
The medicolegal system relies on the ability of experts and non-experts alike to make judgments about expertise and use those judgments to reach consequential decisions. Given the lack of standard criteria, mandatory certification, or licensure for establishing expertise required to practice forensic anthropology and testify as an expert witness, we sought to understand how individuals assess and identify expertise in forensic anthropology by using a social science tool called the Imitation Game. This tool assesses immersion in a specific area of study via discourse, with the premise that some individuals lacking expertise themselves imitate or attempt to pass as experts. For this project we recruited volunteers with varying expertise in forensic anthropology to participate in interviews which asked questions about the practice and structure of the discipline. Those interviews were transcribed, anonymized, and evaluated by other recruited individuals with varying expertise in forensic anthropology. Results found that judges who were experts in forensic anthropology performed better than non-expert judges in determining who was not an expert in forensic anthropology based on their anonymized responses; however, nearly half of the non-experts were still able to pass as experts in forensic anthropology. The difficulties in assessing expertise based on discourse interactions demonstrates the value and need for well-defined credentials and mandatory certification to practice forensic anthropology. This study demonstrates that accurately identifying expertise in forensic anthropology may be challenging for both experts and non-experts, especially when relying solely on interactional expertise rather than formal assessments of competency which directly elucidate contributory expertise.  相似文献   
212.
    
Bone samples are valuable for examining the cause of death and circumstance leading up to death when body fluids are not available for forensic toxicological analysis. Examined were heat-induced changes in methamphetamine and amphetamine concentrations in femurs removed from methamphetamine-injected mice to determine if the burned bones could be used for toxicology testing. The femurs were heated at 100°C, 300°C, or 500°C for 10 or 30 min. The tissue structure of the heated femurs was preserved at 100°C for 30 min but was destructed at higher temperatures. Methamphetamine and amphetamine were detected in femurs heated at 100°C for 10 min, 100°C for 30 min, and 300°C for 10 min (with methamphetamine and amphetamine concentrations ranging from 0.36 to 35 μg/g and 0.54 to 47 μg/g, respectively). Methamphetamine and amphetamine were detectable when heated above their decomposition temperature as a result of limited heat transfer do to protection provide by the femoral muscle. Thus, the bone could be a useful analytical sample in cases of burn-related deaths, where it is difficult to collect body fluids.  相似文献   
213.
More than two decades ago, Marmarou published a valid model for producing diffuse axonal injury (DAI) in rats. Since then, both mild and severe injuries have been obtained by researchers using the original method and a weight of 450 g. However, the diffuse brain injuries produced in rats were only similar to those seen in humans when the rats sustained severe brain injuries. In these cases, rat mortality in the original article was around 50%, and the cause of death was prolonged apnea post-impact. Rat survival after impact is critical for studying the progression of DAI. In order to explain the cause of death in human victims with cranial trauma who do not show gross brain injury, testing for the presence of DAI is essential. Thus, in order to minimize local and cervical injuries to increase rat survival, attention should be paid to the following aspects: a wider head protector disc should be used, the head of the rat should be elevated at the time of impact, and the foam bed should be soft enough to allow the movement caused by acceleration. With our modified method, rat survival increased by 30% compared to the original model (80% versus 50%). Moreover, 85.7% of rats demonstrated DAI after 24 h of survival. With these modifications, injuries appear in the same locations as in humans; thus, the method is suitable for the study of traumatic DAI in humans.  相似文献   
214.
    
Definitive identification of fentanyl analogs based on mass spectral comparison is challenging given the high degree of structural and, hence, spectral similarity. To address this, a statistical method was previously developed in which two electron-ionization (EI) mass spectra are compared using the unequal variance t-test. Normalized intensities of corresponding ions are compared, testing the null hypothesis (H0) that the difference in intensity is equal to zero. If H0 is accepted at all m/z values, the two spectra are statistically equivalent at the specified confidence level. If H0 is not accepted at any m/z value, then there is a significant difference in intensity at that m/z value between the two spectra. In this work, the statistical comparison method is applied to distinguish EI spectra of valeryl fentanyl, isovaleryl fentanyl, and pivaloyl fentanyl. Spectra of the three analogs were collected over a 9-month period and at different concentrations. At the 99.9% confidence level, the spectra of corresponding isomers were statistically associated. Spectra of different isomers were statistically distinct, and ions responsible for discrimination were identified in each comparison. To account for inherent instrument variations, discriminating ions for each pairwise comparison were ranked based on the magnitude of the calculated t-statistic (tcalc) value. For a given comparison, ions with higher tcalc values are those with the greatest difference in intensity between the two spectra and, therefore, are considered more reliable for discrimination. Using these methods, objective discrimination among the spectra was achieved and ions considered most reliable for discrimination of these isomers were identified.  相似文献   
215.
    
Touch DNA has become increasingly important evidence in todays' forensic casework. However, due to its invisible nature and typically minute amounts of DNA, the collection of biological material from touched objects remains a particular challenge that underscores the importance of the best collection methods for maximum recovery efficiency. So far, swabs moistened with water are often utilized in forensic crime scene investigations for touch DNA sampling, even though an aqueous solution provokes osmosis, endangering the cell's integrity. The aim of the research presented here was to systematically determine whether DNA recovery from touched glass items can be significantly increased by varying swabbing solutions and volumes compared with water-moistened swabs and dry swabbing. A second objective was to investigate the possible effects of storage of swab solutions prior to genetic analysis on DNA yield and profile quality when stored for 3 and 12 months, as is often the case with crime scene samples. Overall, the results indicate that adapting volumes of the sampling solutions had no significant effect on DNA yield, while the detergent-based solutions performed better than water and dry removal, with the SDS reagent yielding statistically significant results. Further, stored samples showed an increase in degradation indices for all solutions tested, but no deterioration in DNA content and profile quality, allowing for unrestricted processing of touch DNA samples stored for at least 12 months. One further finding was a strong intraindividual change in DNA amounts observed over the 23 deposition days which may be related to the donor's menstrual cycle.  相似文献   
216.
The most highly cited forensic practitioners in the United States were identified using a publicly available citation database that used six different citation metrics to calculate each person's composite citation score. The publication and citation data were gleaned from Elsevier's SCOPUS database, which contained information about ~7 million scientist each of whom had at least five entries in the database. Each individual was categorized into 22 scientific fields and 176 subfields, one of which was legal and forensic medicine (LFM). The database contained citation records for 13,388 individuals having LFM as their primary research discipline and 282 of these (2%) were classified as being highly cited. Another 99 individuals in the database had LFM as their secondary discipline, making a total of 381 highly cited forensic practitioners from 35 different countries. The career-long publication records of each individual were compared using their composite citation scores. Of the 381 highly cited scientists, 93 (24%) had an address somewhere in the United States. The various branches of forensics they specialized in were anthropology, criminalistics, DNA/genetics, odontology, pathology, statistics/epidemiology, and toxicology. The two most highly cited scientists, according to their composite citation score, were both specialists in DNA/genetics. Bibliometric methods are widely used for evaluating research performance in academia and a similar approach might be useful in jurisprudence, such as when an expert witness is instructed to testify in court and explain the meaning of scientific evidence.  相似文献   
217.
    
In order to detect latent fingerprints that could be damaged by liquid or powder reagents, non-destructive processes such as gaseous reagents have been developed. In this report, we propose the use of fine mist generated when hot vapor of high-boiling-point liquids is rapidly cooled by surrounding air for fingermark detection. Octyl acetate (OA), 2-phenoxyethanol (2PE), and methyl decanoate (MD) were found to efficiently produce mist when heated to 230°C. By combining these liquids with p-dimethylaminocinnamaldehyde (DMAC) and cyanoacrylate (CN), our team demonstrated effective fluorescence staining of cyano-treated fingermarks using DMAC/OA misting or DMAC/2PE misting, and one-step fluorescence detection of latent fingermarks without cyanoacrylate treatment using DMAC/OA/CN misting or DMAC/MD/CN misting. Fingermark fluorescence was efficiently observed by excitation with a blue LED light (max. wavelength 470 nm) equipped with an interference filter and passing through a 520 nm long-pass filter. We successfully obtained fluorescent images from fingermarks on several substrate materials using the developed misting method.  相似文献   
218.
    
Drawing forensic conclusions from an image or a video is known as “photographic content analysis.” It involves the analysis of an image, as well as objects, actions, and events depicted in images or video. In recent years, photographic depictions of objects suspected as illegal firearms have substantially increased, appearing on CCTV surveillance footage, captured by mobile phones and shared on social media. However, the law in Israel states that a person can be charged with illegally possessing a firearm only if it can be proven that the object is capable of shooting with lethal bullet energy. This becomes more challenging in cases where the firearm was not physically seized, and the evidence exclusively consists of images and video. In this study, photographic content analysis was applied to images and video where objects suspected as commercial or improvised firearms had been depicted. An image and event sequence reconstruction video databases of both firearms and replicas were created in order to better define firearm-specific functional morphological features. We demonstrate that it is possible to classify an object as a firearm by analyzing the functional, and not only the esthetic, morphology in images and video. It is also shown that event sequence reconstruction in video may be used to infer that an object suspected as a firearm has the capacity to shoot by confirming the occurrence of a shooting act or shooting process. Thus, photographic content analysis may be used to forensically establish that an object depicted in an image or a video is a firearm by ruling out other known scenarios, and without physically seizing it.  相似文献   
219.
    
While denial of pregnancy and neonaticide are rare, they are potentially associated and share some risk factors. Neonaticide has been proposed as the extreme outcome of a denial of pregnancy. However, the process leading to such a possible outcome is not yet fully understood. The primary goal of this essay is to examine the various definitions and ambiguities surrounding the denial of pregnancy. The case of a young woman with a history of two denied pregnancies with diverse characteristics and outcomes, the latest of which resulted in neonaticide, is then reported and examined. A forensic psychiatric evaluation was also performed to reconstruct the woman's mental state at the time of the crime. The forensic pathological analysis of the newborn, abandoned near the sea while still alive, is described. The victim's body showed signs of shaken baby syndrome. We contend that differing levels of awareness during a denial of pregnancy might not be predictive of the potential delivery outcome in terms of threat to the newborn's survival, according to the forensic pathological and psychopathological data of the current case. Early identification of women affected by denial of pregnancy who pose a danger of committing infanticide is hampered by both intrinsic traits (dissimulation, unawareness, low propensity to seek assistance) and environmental factors (isolation, low socioeconomic level, poor education.). A previous history of denial of pregnancy should activate health and support services to reduce the potential risks for the mother and the child.  相似文献   
220.
    
The last few years have witnessed the change in the modalities of smuggling of synthetic cannabinoid receptor agonists (SCRAs) by impregnating them in mail envelopes and fast parcels. Considering the aforementioned scenario, it is important to develop a portable technique to identifying SCRAs through packages. The purpose of this research was to detect SCRAs impregnated into substrates of paper using attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy. Three SCRAs that included 5F-PB-22, AB-FUBINACA and AKB-48 were purchased from Sigma Aldrich. The three SCRAs and four cutting agents were impregnated into paper of variable thickness at four concentrations (10, 15, 20, and 25 mg/mL). Spectra were collected over the wavenumber range of 650–4000 cm−1 using ATR-FTIR spectroscopy and were exported to Matlab 2020b where data analysis was applied. The FTIR spectral data was able to show the three SCRAs could be detected on paper using ATR-FTIR spectroscopy and quantitatively modeled using the partial least squares regression algorithm. Principal component analysis showed separate clustering for the compounds that crystallized (5F-PB-22, AB-FUBINACA and caffeine) onto the papers surface from those impregnated into the bulk of the paper (AKB-48 and procaine) with the latter situated near blank papers in score plots. In summary, ATR-FTIR spectroscopy has proven to be a successful non-destructive technique in detecting and quantifying a selection of SCRAs impregnated into paper.  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