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261.
Determination of Nitrite in Whole Blood by High‐Performance Liquid Chromatography with Electrochemical Detection and a Case of Nitrite Poisoning 下载免费PDF全文
Hui Yan M.Sc. Xiangyi Zhuo B.Sc Baohua Shen M.Sc. Ping Xiang Ph.D. Min Shen M.Sc. 《Journal of forensic sciences》2016,61(1):254-258
Although nitrite is widely used in meat processing, it is a major toxicity hazard to children and is responsible for the blue‐baby syndrome. A simple and effective method to determine nitrite in whole blood has been devised using ion chromatography with suppressed conductivity detection. The blood sample was deproteinized by adding acetonitrile and purified with mini‐cartridges to remove hydrophobic compounds, chloride ions, and metal ions. An aliquot of the filtrate was injected onto the ion chromatography. The retention time for nitrite was 13.8 min and the detection limit of nitrite in whole blood was 0.4 μmol/L. The calibration curve was linear (r2 = 0.9999) over the concentration working range. The blood nitrite concentration of a victim who attempted suicide by ingesting sodium nitrite powder was determined using the present method. The basal levels for nitrite in human blood was determined with 7.1 ± 0.9 μmol/L (n = 12). 相似文献
262.
Measurement of Uncertainty for Aqueous Ethanol Wet‐Bath Simulator Solutions Used with Evidential Breath Testing Instruments 下载免费PDF全文
Rong‐Jen Hwang Ph.D. Jada Beltran B.A. Craig Rogers B.A. Jeremy Barlow M.S. Gerasimos Razatos M.B.A. B.S. 《Journal of forensic sciences》2016,61(5):1359-1363
Aqueous ethanol wet‐bath simulator solutions are used to perform calibration adjustments, calibration checks, proficiency testing, and inspection of breath alcohol instruments. The Toxicology Bureau of the New Mexico Department of Health has conducted a study to estimate a measurement of uncertainty for the preparation and testing of these wet‐bath simulator solutions. The measurand is identified as the mass concentration of ethanol (g/100 mL) determined through dual capillary column headspace gas chromatography with flame ionization detector analysis. Three groups were used in the estimation of the aqueous ethanol wet‐bath simulator solutions uncertainty: GC calibration adjustment, GC analytical, and certified reference material. The standard uncertainties for these uncertainty sources were combined using the method of root‐sum‐squares to give uc = 0.8598%. The combined standard uncertainty was expanded to U = 1.7% to reflect a confidence level of 95% using a coverage factor of 2. This estimation applies to all aqueous ethanol wet‐bath simulator solution concentrations produced by this laboratory. 相似文献
263.
目的研究服用藿香正气水后,大鼠体内乙醇含量及药代动力学参数的变化。方法将大鼠随机分为3组,分别按3.0 m L/kg剂量灌胃白酒、低浓度中药酒和高浓度中药酒,于给药前(0 min)和给药后5 min、10 min、15 min、30 min、1 h、2 h、3 h、4 h、5 h、6 h、8 h断尾采血,用顶空-气相色谱法测定大鼠血液中的乙醇含量,用DAS 2.0软件计算乙醇的药代动力学参数,SPSS 17.0软件对药代动力学参数进行分析。结果高浓度中药酒组与白酒组最大血药浓度相比,差异有统计学意义(P0.05);其他药代动力学参数在三组间差异均无统计学意义(P0.05)。结论藿香正气水中中药成分对大鼠体内乙醇代谢和消除无明显影响。本研究对涉及饮用藿香正气水导致的交通案(事)件的定性判定和处理以及药物间的相互作用研究具有参考意义。 相似文献
264.
265.
Arun S. Moorthy PhD Edward P. Erisman MS Anthony J. Kearsley PhD Yuxue Liang PhD Edward Sisco PhD William E. Wallace PhD 《Journal of forensic sciences》2023,68(5):1494-1503
Fentanyl analogs are a class of designer drugs that are particularly challenging to unambiguously identify due to the mass spectral and retention time similarities of unique compounds. In this paper, we use agglomerative hierarchical clustering to explore the measurement diversity of fentanyl analogs and better understand the challenge of unambiguous identifications using analytical techniques traditionally available to drug chemists. We consider four measurements in particular: gas chromatography retention indices, electron ionization mass spectra, electrospray ionization tandem mass spectra, and direct analysis in real time mass spectra. Our analysis demonstrates how simultaneously considering data from multiple measurement techniques increases the observable measurement diversity of fentanyl analogs, which can reduce identification ambiguity. This paper further supports the use of multiple analytical techniques to identify fentanyl analogs (among other substances), as is recommended by the Scientific Working Group for the Analysis of Seized Drugs (SWGDRUG). 相似文献
266.
反相高效液相色谱法测定人血浆中的吲哚美辛 总被引:2,自引:0,他引:2
建立血浆中吲哚美辛的高效液相色谱分析方法 ,扩大药 (毒 )物检测范围及手段 ,以适应法医学鉴定的特殊需要。以空白血浆标准添加吲哚美辛对样品处理方法、线性关系、回收率及精度进行考察 ,并以所建方法对健康受试者的血液浓度进行监测。方法的线性范围是 0 1~ 5 0 μg·ml-1,γ =0 9995 ,最小检出浓度为 0 0 2 μg·ml-1(S/N≥ 3)。日内、日间的方法精密度为 ( 1 1± 0 2 ) % (n =4)和 ( 2 7± 0 6 ) % (n =4) ,加样回收率为 97 5 %~10 4 2 %。所建方法准确、便捷、选择性好 ,可用于法医学鉴定及血液浓度监测 相似文献
267.
介绍了敌鼠和溴敌隆抗凝血杀鼠药的定性定量分析方法.在酸性条件下,选用液-液提取和C_(18)柱固相萃取方法处理生物样品,用高效液相色谱法和薄层色谱方法定性定量分析.方法适用于中毒案件的检验. 相似文献
268.
目的研究木瓜的薄层色谱鉴别特征,探索建立木瓜薄层色谱鉴别的的专属性方法。方法采用硅胶G板和聚酰胺薄膜分离鉴别木瓜中有机酸和鞣质成分。结果两种薄层色谱方法均能检出木瓜的有机酸以及鞣质类组分群,其中有机酸类成分的鉴别更具有应用意义。结论薄层色谱法简便、重现性好、专属性强,可用于木瓜的薄层鉴别。 相似文献
269.
The intention of this study was to differentiate liquid gasoline samples from casework by utilizing multivariate pattern recognition procedures on data from gas chromatography-mass spectrometry. A supervised learning approach was undertaken to achieve this goal employing the methods of principal component analysis (PCA), canonical variate analysis (CVA), orthogonal canonical variate analysis (OCVA), and linear discriminant analysis. The study revealed that the variability in the sample population was sufficient enough to distinguish all the samples from one another knowing their groups a priori. CVA was able to differentiate all samples in the population using only three dimensions, while OCVA required four dimensions. PCA required 10 dimensions of data in order to predict the correct groupings. These results were all cross-validated using the "jackknife" method to confirm the classification functions and compute estimates of error rates. The results of this initial study have helped to develop procedures for the application of multivariate analysis to fire debris casework. 相似文献
270.
目的建立血中杀参毒素类农药残留的快速分析方法。方法取一定量的Al2O3放入萃取池中做吸附剂,通过快速溶剂萃取仪萃取血液中杀参毒素类农药,同时达到在线净化的效果,后运用凝胶色谱净化联用仪进一步净化浓缩到2ml,提取液经LC/MS/MS进行检验。结果杀虫双在1.2×10g/ml~1.2×10^-6g/ml范围内线性关系良好,检出限为0.04ppb,杀虫眯为1.2×10^-6g/ml~7.2×10g/ml,检出限为0.34ppm。2种杀参毒素农药的平均回收率为89%、90%,相对标准偏差为1.9%、3%。结论整个方法简便、快速、准确、重现性好、灵敏度高,杂质干扰少。 相似文献