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排序方式: 共有278条查询结果,搜索用时 15 毫秒
21.
目的建立测定血液中美西律(mexiletine)的液相色谱-串联质谱联用法(LC-MS/MS)。方法采用简便的乙腈蛋白沉淀法对血液进行预处理,应用Allure PFP Propyl液相柱分离,用电喷雾正离子模式离子化,多反应监测模式对美西律进行分析。结果美西律与内标纳洛酮分离良好,在0.02~10.00μg/mL内线性关系良好,相关系数为0.9999,回归方程为y=0.0283x-0.0151,日内与日间精密度的RSD均小于15%,最低检测限为0.01μg/mL。结论建立的LC-MS/MS方法简单、灵敏、可靠,可同时适用于美西律临床药物监测和法医毒物分析的需要。 相似文献
22.
杨黎华 《广西警官高等专科学校学报》2012,(1):28-30
吸毒驾车已成为一个巨大的交通安全隐患,具有较大的社会危害性。目前,中国对于吸毒驾车的管制存在法律不完备、主体不明确、检测吸毒困难等问题。有效管制吸毒驾车,可以借鉴国外的查处方法,同时要加快立法,建立制约机制、相关数据库和预警平台,适时集中进行专项整治,推广新型吸毒检测方法。 相似文献
23.
Schäffer M Gröger T Pütz M Dieckmann S Zimmermann R 《Journal of forensic sciences》2012,57(5):1181-1189
Abstract: The chemical profiling of illicit drugs is an important analytical tool to support the work of investigating and law enforcement authorities. In our work, comprehensive two‐dimensional gas chromatography–time‐of‐flight mass spectrometry (GC × GC‐TOFMS) combined with nontargeted, pixel‐based data analysis was adapted for the chemical profiling of 3,4‐methylenedioxymethamphetamine (MDMA). The validity and benefit of this approach was evaluated by analyzing a well‐investigated set of MDMA samples. Samples were prepared according to a harmonized extraction protocol to ensure the comparability of the chemical signatures. The nontargeted approach comprises preprocessing followed by analysis of variances as a fast filter algorithm for selection of a variable subset followed by partial least squares discriminant analysis for reduction to promising marker compounds for discrimination of the samples according to their chemical profile. Forty‐seven potential marker compounds were determined, covering most of the target impurities known from the harmonized one‐dimensional profiling as well as other compounds not previously elucidated. 相似文献
24.
近年来,苯丙胺类兴奋剂的β酮(bK)策划药相继在许多国家的毒品市场中出现,由于该类物质潜在的依赖性和已经导致的死亡事件,许多国家已经将其列为管制的物质。本文介绍了通过GC/MS和LC/MS方法对苯丙胺类兴奋剂的衍生物4-甲基甲卡西酮、bk-MDMA、bk-MBDB和bk-MDEA检测的相关研究结果,以说明其主要代谢途径。以期为临床医学、法庭毒理学以及禁毒机构监控该类物质提供参考。 相似文献
25.
This study takes the first step toward in situ analysis of powder drugs which does not require any alteration of the samples. A fast, inexpensive analytical method based on reflectance near-infrared (NIR) spectrometry and multivariate calibration was applied. A diode-array fiber-optic portable spectrometer in the 900-1700 nm range was employed. Samples were laboratory-prepared ternary powders (diacetylmorphine, caffeine, and paracetamol). Partial least squares regression was applied. The choice of the standard samples for calibration and validation was performed through a D-optimal experimental design. The explained variance was higher than 90%, and the relative root mean square errors were <2%. The number of principal components (6) was very low when compared with the number of raw variables (356 absorbance values). Response plots showed slopes and intercepts were very close to optimal values. Correlation coefficients ranged between 0.909 and 0.989. The method here proposed proved to be competitive with Fourier transform NIR spectrometry. 相似文献
26.
《Justice Quarterly》2012,29(4):517-537
Analyses of the impact on sentencing when alcohol and drug‐related mitigation is used in the sentencing phases of capital murder trials is virtually absent from the existing literature. The present study addresses this by exploring the effect of having mitigation with alcohol and drug themes accepted in a large sample (n = 804) of capital murder trials in North Carolina. Logistic regression analyses that include a number of relevant control variables reveal no substantive impacts of having alcohol mitigation accepted by capital murder juries, but drug mitigators that were either accepted or rejected by juries were associated with an increased risk of receiving a death sentence. Possible reasons for the results and their implications are discussed and suggestions are made for further study of the effects of alcohol/drug mitigation in capital trials. 相似文献
27.
The case of a 22‐year‐old male Caucasian driver is presented. He was involved in a traffic collision. At the roadside, he displayed blank stare and mellow speech with a barely audible voice. A DRE found low body temperature, rigid muscle tone, normal pulse, lack of horizontal and vertical gaze nystagmus, nonconvergence of the eyes, dilated pupil size, and normal Pupillary reaction to light. A standard toxicology DUID protocol was performed on the driver's whole blood including ELISA and GC‐MS drug screens with negative results. Additional drug screening was undertaken for bath salts and synthetic cannabinoid receptor agonists by LC‐MS/MS by a commercial laboratory and identified the synthetic cannabinoid receptor agonist XLR‐11 in the driver's blood. XLR‐11 was subsequently quantified at 1.34 ng/mL. This is the first documented case involving a driver operating a motor vehicle under the influence of the synthetic cannabinoid receptor agonist XLR‐11. 相似文献
28.
液相色谱-质谱联用同时检测17种常见毒品的定性分析方法 总被引:3,自引:0,他引:3
目的 建立同时检测17种常见毒品的液相色谱-质谱联用定性分析方法.方法 对海洛因、吗啡、冰毒、氯胺酮等17种毒品的色谱行为进行了研究,对流动相梯度程序和质谱参数进行了细致考察和优化.采用岛津Shim-pack XR-ODS(100mm×2.0mm,2.2μm)色谱柱,流动相A:0.3%甲酸;流动相B:0.3甲酸乙腈,梯度洗脱程序0min~3min~8min~15min~20min,3%B~18%B~23%B~93%B~93%B,雾化电压5kV,扫描速度3750u/sec,雾化气流量1.5L/min,干燥气流量10L/min.结果 所测17种毒品的21种组分均获得了良好的分离效果和质谱响应,scan模式下检测限(S/N≥3)1.9pg/μL~40.0pg/μL.结论 该方法快速、简便、高效,适合公安办案中对未知毒品进行定性检测. 相似文献
29.
30.
Organic impurity profiling of fentanyl samples associated with recent clandestine laboratory methods
Steven G. Toske PhD Jennifer R. Mitchell MS James M. Myslinski PhD Andrew J. Walz PhD David B. Guthrie PhD Elizabeth M. Guest PhD Charlotte A. Corbett PhD Emily D. Lockhart MS 《Journal of forensic sciences》2023,68(5):1470-1483
Nearly a decade ago, fentanyl reappeared in the United States illicit drug market. In the years since, overdose deaths have continued to rise as well as the amount of fentanyl seized by law enforcement agencies. Research surrounding fentanyl production has been beneficial to regulatory actions and understanding illicit fentanyl production. In 2017, the Drug Enforcement Administration (DEA) began collecting seized fentanyl samples from throughout the United States to track purity, adulteration trends, and synthetic impurity profiles for intelligence purposes. The appearance of a specific organic impurity, phenethyl-4-anilino-N-phenethylpiperidine (phenethyl-4-ANPP) indicates a shift in fentanyl production from the traditional Siegfried and Janssen routes to the Gupta-patent route. Through a collaboration between the DEA and the US Army's Combat Capabilities Development Command Chemical Biological Center (DEVCOM CBC), the synthesis of fentanyl was investigated via six synthetic routes, and the impurity profiles were compared to those of seized samples. The synthetic impurity phenethyl-4-ANPP was reliably observed in the Gupta-patent route published in 2013, and its structure was confirmed through isolation and structure elucidation. Organic impurity profiling results for illicit fentanyl samples seized in late 2021 have indicated yet another change in processing with the appearance of the impurity ethyl-4-anilino-N-phenethylpiperidine (ethyl-4-ANPP). Through altering reagents traditionally used in the Gupta-patent route, the formation of this impurity was determined to occur through a modification of the route as originally described in the Gupta patent. 相似文献