全文获取类型
收费全文 | 870篇 |
免费 | 9篇 |
专业分类
各国政治 | 77篇 |
工人农民 | 23篇 |
世界政治 | 103篇 |
外交国际关系 | 44篇 |
法律 | 517篇 |
中国共产党 | 1篇 |
中国政治 | 4篇 |
政治理论 | 99篇 |
综合类 | 11篇 |
出版年
2024年 | 3篇 |
2023年 | 26篇 |
2022年 | 10篇 |
2021年 | 24篇 |
2020年 | 40篇 |
2019年 | 39篇 |
2018年 | 48篇 |
2017年 | 52篇 |
2016年 | 56篇 |
2015年 | 30篇 |
2014年 | 37篇 |
2013年 | 166篇 |
2012年 | 45篇 |
2011年 | 23篇 |
2010年 | 25篇 |
2009年 | 36篇 |
2008年 | 34篇 |
2007年 | 37篇 |
2006年 | 20篇 |
2005年 | 10篇 |
2004年 | 18篇 |
2003年 | 18篇 |
2002年 | 15篇 |
2001年 | 12篇 |
2000年 | 12篇 |
1999年 | 10篇 |
1998年 | 4篇 |
1997年 | 3篇 |
1996年 | 3篇 |
1995年 | 3篇 |
1994年 | 3篇 |
1993年 | 1篇 |
1992年 | 5篇 |
1991年 | 2篇 |
1990年 | 1篇 |
1989年 | 3篇 |
1988年 | 1篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1983年 | 1篇 |
排序方式: 共有879条查询结果,搜索用时 31 毫秒
811.
目的建立生物样品中百草枯(paraquat,PQ)及其2种主要代谢物monoquat,paraquatmonopyridone(MP)的液相色谱-串联质谱(LC-MS/MS)检测方法,应用于百草枯中毒案件的法医学鉴定。方法生物样品经乙腈或甲醇沉淀蛋白,使用Agilent HILIC Plus(4.6×100mm,3.5μm)色谱柱,以0.1%甲酸水溶液~0.1%甲酸乙腈溶液(v/v)为流动相进行洗脱,在多反应监测模式下检测。结果百草枯及其代谢物在1~1000ng/mL内线性关系良好,相关系数(r)≥0.9996,最低检出限为0.34~6.00ng/mL,检测准确度为91.25%~113.44%,日内及日间精密度分别为1.51%~3.99%和1.92%~4.93%。结论本文建立的LC-MS/MS法具有灵敏度高、特异性好的特点,可应用于百草枯中毒相关案件的法医学鉴定。 相似文献
812.
Miguel de la Corte Rodríguez 《社会福利与家庭法律杂志》2018,40(3):376-393
The current European Union (EU) legislative framework on child-related leave is facilitating an imbalance in the take-up of leave by women over men. There is a consolidated EU right to maternity leave for mothers but there is no parallel EU right to paternity leave for fathers. The EU right to parental leave is for both working mothers and fathers, but its design does not encourage an equal take-up by women and men. The aim of this article is to gain insight into the effects of child-related leave on women’s labour market outcomes. On the one hand, it reviews and analyses economic literature which points to the adverse consequences of leave on women’s earnings, and even on women’s labour market participation when the absences from work are very prolonged. On the other hand, it underlines the new direction followed by the European Commission towards greater equality between men and women at home and at work. 相似文献
813.
At outdoor crime scenes, cadaver-detection and blood-detection dogs may be tasked with locating blood that is days, weeks or months old. Although it is known that the odour profile of blood will change during this time, it is currently unknown how the profile changes when exposed to the environment. Such variables must be studied in order to understand when the odour profile is no longer detectable by the scent-detection dogs and other crime scene tools should be implemented. In this study, blood was deposited onto concrete and varnished wood surfaces and weathered in an outdoor environment over a three-month period. Headspace samples were collected using solid phase microextraction (SPME) and analysed using comprehensive two-dimensional gas chromatography – time-of-flight mass spectrometry (GC×GC–TOFMS). The chemical odour profiles were compared with the behavioural responses of cadaver-detection and blood-detection dogs during training. Data interpretation using principal component analysis (PCA) and hierarchical cluster analysis (HCA) established that the blood odour could no longer be detected using SPME–GC×GC–TOFMS after two months of weathering on both surfaces. Conversely, the blood-detection dogs had difficulty locating the blood samples after one month of weathering on concrete and after one week of weathering on varnished wood. The scent-detection dogs evaluated herein had not been previously exposed to environmentally weathered blood samples during training. Given that this study was conducted to test the dogs' baseline abilities, it is expected that with repeated exposure, the dogs' capabilities would likely improve. The knowledge gained from this study can assist in providing law enforcement with more accurate training aids for blood-detection dogs and can improve their efficiency when deployed to outdoor crime scenes. 相似文献
814.
Michelle Wood Marleen Laloup Maria del Mar Ramirez Fernandez Kevin M. Jenkins Michael S. Young Jan G. Ramaekers Gert De Boeck Nele Samyn 《Forensic Science International Supplement Series》2005,150(2-3):227
We present a validated method for the simultaneous analysis of basic drugs which comprises a sample clean-up step, using mixed-mode solid-phase extraction (SPE), followed by LC–MS/MS analysis. Deuterated analogues for all of the analytes of interest were used for quantitation. The applied HPLC gradient ensured the elution of all the drugs examined within 14 min and produced chromatographic peaks of acceptable symmetry. Selectivity of the method was achieved by a combination of retention time, and two precursor-product ion transitions for the non-deuterated analogues. Oral fluid was collected with the Intercept®, a FDA approved sampling device that is used on a large scale in the US for workplace drug testing. However, this collection system contains some ingredients (stabilizers and preservatives) that can cause substantial interferences, e.g. ion suppression or enhancement during LC–MS/MS analysis, in the absence of suitable sample pre-treatment. The use of the SPE was demonstrated to be highly effective and led to significant decreases in the interferences. Extraction was found to be both reproducible and efficient with recoveries >76% for all of the analytes. Furthermore, the processed samples were demonstrated to be stable for 48 h, except for cocaine and benzoylecgonine, where a slight negative trend was observed, but did not compromise the quantitation. In all cases the method was linear over the range investigated (2–200 μg/L) with an excellent intra-assay and inter-assay precision (coefficients of variation <10% in most cases) for QC samples spiked at a concentration of 4, 12 and 100 μg/L. Limits of quantitation were estimated to be at 2 μg/L with limits of detection ranging from 0.2 to 0.5 μg/L, which meets the requirements of SAMHSA for oral fluid testing in the workplace. The method was subsequently applied to the analysis of Intercept® samples collected at the roadside by the police, and to determine MDMA and MDA levels in oral fluid samples from a controlled study. 相似文献
815.
816.
全血中度冷丁的气—联用法测定及代谢动力学的研究 总被引:1,自引:0,他引:1
应用气-质联用选择离子法测定全血中度冷丁的浓度。方法线性范围为0.002~1ng/ml(r=0.9997),变异系数小于10%,最低检测限过1ng/ml,无杂质干扰。本法已用于肌注80mg度冷丁后代谢动力学的研究。 相似文献
817.
Alf Gunvald Nilsen 《当代亚洲杂志》2015,45(4):574-595
AbstractFocusing on recent debates over the ways in which subaltern groups engage with the state in India, the article proposes that it is imperative to historicise our conceptions of subaltern politics in India. More specifically, the argument is made that it is imperative to recognise that subaltern appropriations of the institutions and discourses of the state have a longer historical lineage than what is often proposed in critical work on popular resistance in rural India. The article presents a detailed analysis of Adivasi rebellions in colonial western India and argues that these took the form of a contentious negotiation of the incorporation of tribal communities into an emergent “colonial state space.” The conclusion presents a sketch of a Gramscian approach to the study of how subaltern politics proceeds in and through determinate state–society relations. 相似文献
818.
Karim M. Abdel‐Hay Ph.D. Jack DeRuiter Ph.D. C. Randall Clark Ph.D. 《Journal of forensic sciences》2015,60(2):285-294
A number of N‐substituted piperazines have been described as drugs of abuse in recent years. This new drug category includes several series of aromatic ring substituted phenylpiperazines. The wide variety of available precursors makes regioisomerism a significant issue in these totally synthetic compounds. In this study, a complete series of regioisomeric dimethoxyphenylpiperazines were synthesized and evaluated using GC‐MS and FT‐IR. The EI mass spectra show fragments characteristic of both the dimethoxyphenyl and the piperazine portions of the molecules including the dimethoxyphenylaziridinium cation (m/z 180) and dimethoxyphenyl cation (m/z 137). The ion at m/z 56 for the C3H6N+ fragment is characteristic of the piperazine ring and was observed in all the spectra. The perfluoroacyl derivatives were resolved by GC, and their mass spectra showed some differences in relative abundance of ions. FTIR provides direct confirmatory data for differentiation between the regioisomeric dimethoxyphenylpiperazines, and GC separation was accomplished on an Rtx‐200 phase. 相似文献
819.
超高效液相色谱-MS/MS法测定血中11种苯丙胺类物质 总被引:1,自引:1,他引:0
目的应用超高效液相色谱-质谱法对全血中11种苯丙胺类毒品进行定量测定。方法全血样品经1%(v/v)甲酸-乙腈提取,采用Ostra磷脂过滤板净化处理,使用ACQUITY UPLC BEH Phenyl(100mm×2.1mm,1.7μm)色谱柱,以0.3%(v/v)甲酸溶液-乙腈为流动相进行梯度洗脱。在多反应监测模式下测定全血样本中苯丙胺、甲基苯丙胺、二亚甲基双氧苯丙胺、替苯丙胺、3,4-亚甲基二氧基乙基苯丙胺、N-甲基-1-(3,4-亚甲二氧基苯基)-2-丁胺、副甲氧基甲基苯丙胺、麻黄碱、甲基麻黄碱、卡西酮、甲卡西酮,并进行方法学考察。结果 11种苯丙胺类物质的检出限(S/N≥3)为0.01~0.4ng/m L,在0.5~50μg/L范围内线性关系良好(r0.999);回收率在75.8%~103.4%之间,相对标准偏差在1.6%~13.0%之间。结论本文建立的超高效液相色谱-质谱法快速、简便、灵敏,适用于中毒案件检验及吸毒人员排查。 相似文献
820.
目的探讨硫化氢(H2S)中毒者血中H2S的检测及特征鉴别;方法取新鲜空白血液和5℃下保存1月、1年的血液各2m L,经微波低火加热1min后,吸取顶空气体100μL进行GC/PFPD-S、GC/MS检测;取相同样本进行酸化处理后进行检测;取疑似为H2S中毒者血液直接加热后进行检测。结果新鲜血液和5℃下保存1月、1年的血液均可检出H2S成分,但保存1个月以上的血液可同时检出二硫化碳(CS2)成分;酸化处理后的血液,H2S和CS2成分检出的含量明显比未加酸化的血液高;中毒者血液中除了检出H2S成分外,还检出甲硫醚成分。结论血液样本同时检出H2S和较大量的CS2时,不宜判定为H2S中毒,提示可能为腐败所致,而同时检出H2S和较大量的甲硫醚,则可做出H2S中毒的判断。 相似文献