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   656篇
  免费   117篇
各国政治   1篇
工人农民   1篇
世界政治   3篇
外交国际关系   67篇
法律   461篇
中国共产党   4篇
中国政治   42篇
政治理论   8篇
综合类   186篇
  2024年   1篇
  2023年   19篇
  2022年   11篇
  2021年   17篇
  2020年   32篇
  2019年   30篇
  2018年   23篇
  2017年   28篇
  2016年   31篇
  2015年   29篇
  2014年   44篇
  2013年   75篇
  2012年   49篇
  2011年   40篇
  2010年   39篇
  2009年   37篇
  2008年   49篇
  2007年   50篇
  2006年   41篇
  2005年   34篇
  2004年   23篇
  2003年   16篇
  2002年   15篇
  2001年   11篇
  2000年   7篇
  1999年   2篇
  1997年   3篇
  1996年   3篇
  1992年   5篇
  1991年   1篇
  1990年   2篇
  1988年   1篇
  1987年   2篇
  1985年   2篇
  1984年   1篇
排序方式: 共有773条查询结果,搜索用时 31 毫秒
1.
Cyanide is a highly toxic agent that has been frequently used for suicide in South Korea. It is also used in various industrial fields, such as metal plating, in which many accidental cyanide intoxications have occurred. To overcome the disadvantages of conventional cyanide analysis methods, a simple and fast method for the analysis of cyanide in whole blood using ion chromatography (IC) with amperometric detection was developed in this study. Whole blood samples were deproteinized, diluted, and analyzed using an IC–amperometric detection system. The limits of detection and quantitation were 0.1 and 0.2 mg/L, respectively. The method showed good linearity in the range of 0.2 to 50 mg/L with R2 > 0.99. The intra- and inter-assay precision and accuracy values were <10%. The established method was successfully applied to analyze whole blood samples from three cyanide intoxication cases.  相似文献   
2.
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   
3.
过敏性休克导致死亡的案例在法医学实践中常有发生,然而由于缺少特异的病理形态学指征,导致过敏性休克死亡的法医学鉴定面临一定的困难。IgE作为介导I型超敏反应的关键介质,其死后生化学检测对过敏性休克死亡案例的法医学鉴定具有辅助作用。但在实际应用中,血液等检材常受溶血等死后变化因素影响,尤其我国尸体保存以冷冻为主,溶血程度更加严重,对IgE等生化学指标的检测造成极大干扰。本文就目前IgE死后生化学检测的研究现状、生物学检材的选取及检测方法进行综述,并对现实应用中所面临的问题进行探讨。  相似文献   
4.
我国对犯罪嫌疑人的权利保护与过去相比已经有所改善,但仍存在不少问题,刑讯逼供、超期羁押、违反平等比例原则、侵犯犯罪嫌疑人获得帮助和救济的权利等现象时有发生.文章主要针对上述现象提出一些相应的对策.  相似文献   
5.
针对已有资料中对于以DNA为靶基因序列的原位 PCR介绍较多,而对于原位反转录PCR的介绍很少,但在实际研究工作中有很多检测的靶基因是 RNA(病毒的或基因组的 RNA)的实际情况,就原位反转录PCR技术的基本原理、影响试验结果的关键因素和步骤,如组织细胞的固定、引物和探针的选择、蛋白酶及DNA酶消化、假阳性及假阴性的产生等进行了概述,旨在通过探讨上述问题,对该技术的实际应用有所指导。  相似文献   
6.
A method has been developed on reverse phase high performance liquid chromatography for simultaneous determination of methyl, ethyl and isopropyl alcohols under refractive index detection using pure water as the mobile phase. A good separation has been achieved between these alcohols. Detector response was linear with a detection limit of 5 mg/100 ml. Recovery studies were performed by adding known amounts of methyl and ethyl alcohols to blood, lung and liver within the range 80–90%. The reproducibility of the results was always >90%. The quantitative distribution of methyl alcohol in postmortem body tissues and fluids has been reported in three cases of poisoning.  相似文献   
7.
Blood previously acidified with aqueous saturated ammonium chloride solution was extracted with ethyl acetate. The dried extract was subjected to acetonitrile–hexane partition. The acetonitrile portion was analysed for the presence of acidic and neutral drugs by HPLC–DAD (200 mm×2.1 mm I.D. microbore ODS-Hypersil column) and GC–FID (25 m narrow-bore×0.25 mm I.D. HP-5 column with 0.33 μm film thickness). The protocol was found to be suitable for both clinical toxicology (including emergency toxicology) and postmortem toxicology. At least 66 drugs of interest were unequivocally identified by RRTs (HPLC) and UV spectra (DAD) match while another 12 were unequivocally identified by double RRTs match (HPLC and GC). Quantitation was facilitated by incorporating calibration blood standards in each assay batch. The five drugs most commonly encountered in clinical blood specimens (1150 cases) were: paracetamol (47.4% of the cases); chlormezanone (6.6%), theophylline (1.74%), naproxen (1.65%) and mefenamic acid (1.56%). The following drugs were detected in toxicologically significant quantities in postmortem blood specimens (245 cases): phenobarbitone (1.22% of the cases), naproxen (0.82%), chlormezanone (0.82%), theophylline (0.82%), carbamazepine (0.41%) and paracetamol (0.41%).  相似文献   
8.
We show that the probability of apprehension and punishment is usually reduced in a framework with asymmetric information, leading to more offenses being committed. A positive correlation between crime and asymmetry of information in the enforcement process is established. Some suggestions concerning the efficiency of private versus public enforcement are drawn.  相似文献   
9.
Dutch criminality and its relation to the performance of police and justice have only recently been analyzed at the macro level (e.g., at the level of municipalities or the whole country). This type of approach is a useful supplement to analyses at the micro level (that of individuals), which are more common in Dutch empirical criminological research. The main results of such a macro approach are presented in this article. We conclude that the per capita numbers of youth, divorced people, and unemployed contribute significantly to the crime rate. The police strength and solving rates are important factors as well. Analysis of the production process of the police reveals that detecting one more case of driving under the influence is far more expensive than solving one more other crime or handling one more traffic accident. The results are combined to sketch a cost-benefit approach of different strategies in allocating more resources to the police. Allocating extra resources to solving more cases of vandalism gives the best cost-benefit ratio.  相似文献   
10.
建立了一种绵羊血浆中阿维菌素 (AVM )荧光高效液相色谱 (HPLC)检测法。用甲醇提取绵羊血浆中的AVM ,并用ODS C18固相萃取法进行纯化 ,纯化后的AVM经干燥处理后 ,用三氟乙酸酐和N 甲基咪唑对其进行荧光衍生化 ,用荧光HPLC进行检测。本方法的最低检测限为 0 .1ng/mL ,在血浆AVM含量 2 .5~ 5 0 .0ng/mL范围内 ,标准曲线方程为Y =2 72 12x -10 412 (r =0 .9995 ) ,样品的平均回收率为 92 .0 2 %± 6.3 3 %。批内变异系数 1.98%~ 6.2 2 % ,批间变异系数 2 .3 1%~ 8.94%。检测结果显示 ,本方法灵敏度高 ,干扰少 ,重复性好。  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