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   40篇
  免费   3篇
各国政治   1篇
工人农民   2篇
世界政治   2篇
法律   27篇
政治理论   11篇
  2023年   1篇
  2020年   4篇
  2019年   3篇
  2018年   6篇
  2017年   1篇
  2016年   3篇
  2013年   3篇
  2011年   2篇
  2008年   2篇
  2007年   1篇
  2006年   1篇
  2005年   1篇
  2004年   2篇
  2001年   1篇
  2000年   1篇
  1998年   1篇
  1993年   3篇
  1991年   1篇
  1987年   1篇
  1985年   1篇
  1981年   1篇
  1979年   1篇
  1972年   1篇
  1967年   1篇
排序方式: 共有43条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
DNA is one of the fastest growing tools in forensic sciences, increasing reliability in forensic reports and judgments. The use of DNA has increased in different areas of the forensic sciences, such as investigation of plant species, where plastid DNA has been used to elucidate and generate evidence in cases of traceability of genetically modified and controlled plants. Even with several advances and the practice of using DNA in forensic investigations, there are just few studies related to the identification of genetic tools for the characterization of drug and nondrug-types of Cannabis. Herein, the whole plastomes of two drug-type Cannabis are presented and have their structures compared with other Cannabis plastomes deposited in the GenBank, focusing in the forensic use of plastome sequences. The plastomes of Cannabis sativa “Brazuka” and of the hybrid Cannabis AK Royal Automatic presented general structure that does not differs from the reported for other C. sativa cultivars. A phylogenomic analyses grouped C. sativa “Brazuka” with the nondrug C. sativa cultivars, while the hybrid Cannabis AK Royal Automatic placed isolated, basal to this group. This suggests that the analysis of plastomes is useful toward genetic identification of hybrids in relation to C. sativa.  相似文献   
5.
The secondary dentin deposition that occurs after the tooth formation process results in a decrease in pulp cavity volume in adolescents and adults. The purpose of this critical review was to correlate pulpal and/or dental volume on cone-beam computed tomography (CBCT) with chronological age approximation. A subobjective was to investigate which methodology and CBCT technical parameters would be most appropriate to evaluate this correlation. This critical review followed the PRISMA guidelines, and it was conducted by a search through PubMed, Embase, SciELO, Scopus, Web of Science, Cochrane Library databases, as well as gray literature. Primary studies that used pulp volume, or pulp chamber to tooth volume ratio measured using CBCT were included. Seven hundred and eight indexed and 31 non-indexed records were identified. A qualitative analysis was performed including 25 selected studies with a total of 5100 individuals, age ranging from 8 to 87 years without sex predilection. The most used method was pulp volume/tooth volume. CBCT voxel size ranged between 0.09 and 0.5. Manual segmentation associated with threshold algorithms was used in most of the studies. Correlation between the pulp volume/tooth volume ratio was moderate: −0.66 for the upper central incisors, −0.59 for upper canines and −0.56 for lower canines. High heterogeneity was observed among the studies. It is concluded that pulp volume should be used with caution in age estimation. Evidence supports the preferable use of upper incisors with pulp volume/tooth volume ratio for age estimation. There is not enough evidence that voxel size interferes in age estimation by pulp volume.  相似文献   
6.
Three spectrometric methods, that is, spectrofluorimetry (SF), atomic absorption spectrometry with electrothermal atomization (ET-AAS), and atomic fluorescence spectrometry with hydride generation (HG-AFS) were used for the determination of total selenium in biological samples taken from postmortem material in a case of acute selenium compound poisoning. The precision of the SF, ET-AAS, and HG-AFS methods (RSD, n=10) was found to be in the ranges of 10.0-15.0, 3.0-6.0 and 1.0-1.5%, respectively, and the detection limit was 10.0, 4.0, and 0.1 μg/L of Se, respectively. In the case of HG-AFS, the analytical procedure takes less time and is less laborious than the other methods considered. The obtained results show the usefulness of the HG-AFS method as a supplementary analytical tool to the SF and ET-AAS methods with respect to the determination of selenium as well as the possibility of using this method as a primary one in forensic toxicology practice.  相似文献   
7.
The objective was to investigate color change and surface damage in dental resin composites exposed to high temperatures over different time intervals for comparative purposes. Samples were prepared using two resins - Z100(R) (R1) and Charisma (R2), heated at the following temperatures: 200 degrees C, 400 degrees C, 600 degrees C, 1000 degrees C, for 15, 30 and 45 min (n = 104 for each resin sample). Color (DeltaE) and brightness (DeltaL) changes were analyzed by spectrophotometry using the CIE Lab system and surface changes by Scanning Electron Microscopy (SEM). R1 showed more intense color changes after heat exposure than R2. DeltaL values were found to be the best parameter for evaluation of light and color change. A biphasic pattern after thermal exposure was detected, from dark brown to light white. SEM showed more intense alterations in R2 than in R1. These results indicate that the parameters observed in both resins are useful as a guide in forensic analyses.  相似文献   
8.
Trace DNA analysis is a significant part of a forensic laboratory's workload. Knowing optimal sampling strategies and item success rates for particular item types can assist in evidence selection and examination processes and shorten turnaround times. In this study, forensic short tandem repeat (STR) casework results were reviewed to determine how often STR profiles suitable for comparison were obtained from “handler” and “wearer” areas of 764 items commonly submitted for examination. One hundred and fifty‐five (155) items obtained from volunteers were also sampled. Items were analyzed for best sampling location and strategy. For casework items, headwear and gloves provided the highest success rates. Experimentally, eyeglasses and earphones, T‐shirts, fabric gloves and watches provided the highest success rates. Eyeglasses and latex gloves provided optimal results if the entire surfaces were swabbed. In general, at least 10%, and up to 88% of all trace DNA analyses resulted in suitable STR profiles for comparison.  相似文献   
9.
Love is not often the explicit subject of legal discussion but when it is, it appears as a negative phenomenon that leads us to make bad decisions. This view of love is amplified in the context of commercial and economic transactions, where love, intimacy, and economic exchange are seen as operating under opposing principles. This article questions the accuracy and efficiency of law when it operates under both of these assumptions, and argues for a view that resonates more closely with the more realistic and complex relationship that exists between love and economic exchanges.  相似文献   
10.
The article analyzes the realm of family business to see what a difference the gender of the owner makes. Through the lens of the author's rapid appraisal and/or survey data from field studies in Ecuador, the Dominican Republic, Guatemala, Swaziland, and Guinea-Bissau, three main issues are examined: (1) the use of family in the family business by women and men microentrepreneurs (MEs) — i.e., differential involvement of family members in different work patterns and differential reliance on home-based businesses; (2) similarities and differences in men's vs. women's ventures (type of economic activities, gender composition of employees, loan repayment, reinvestment of profits, etc.); and (3) the impact of the business' income on the ME and his/her family well-being (using hypotheses from my general theory of gender stratification). Finally, implications are extracted concerning the consequences of women's economic empowerment, as well as for Third World microenterprise credit and savings programs.  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