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排序方式: 共有383条查询结果,搜索用时 15 毫秒
71.
目的 建立检测血液和尿液中头孢唑啉、头孢拉定、头孢哌酮和头孢噻肟的高效液相色谱法,并考察方法的适用性.方法 以乙酰苯胺为内标,血液和尿液用乙腈直接沉淀蛋白,采用Agilent Zorbax SB-Aq(250min×4.6mm,5 μm)色谱柱,流动相选用水(含0.12%三乙胺和0.12%乙酸)和乙腈的混合溶剂梯度洗脱,流速1 mL/min,检测波长254nm.结果 4种头孢菌素分离完全,工作曲线相关性均良好(r>0.9990),检出限为0.01μg/mL,回收率均不低于81.2%.结论 所建立的方法对血液和尿液中以上4种头孢菌素的检测快速、简便、准确,适用于实际检案中头孢菌素类药物的分析. 相似文献
72.
目的:建立三七及其制剂三七片中人参皂苷Rg1的含量测定方法。方法:采用反相高效液相色谱法,色谱柱为Teknokroma Kromasil C18(5μm,2.1 cm×15 cm),以乙腈∶0.5 g/L磷酸水溶液(21∶79)为流动相,流速为0.3 ml/min,检测波长为203 nm,柱温为30℃。结果:人参皂苷Rg1浓度为21.4~534μg/ml时,线性关系良好(r=0.9991);平均回收率为99.3%,RSD=1.47%(n=6)。结论:本方法准确、快速、稳定、重现性好,可用于三七药材及其制剂的质量控制。 相似文献
73.
Kenji Tsujikawa Kenji Kuwayama Hajime Miyaguchi Tatsuyuki Kanamori Yuko T. Iwata Takemi Yoshida Hiroyuki Inoue 《Forensic Science International Supplement Series》2008,180(2-3):105-109
Two major salvinorins, salvinorin A (SalA) and salvinorin B (SalB), in three Salvia divinorum dried leaf products and nine of its “concentrated extract” products circulated in Japan were determined. These ingredients were extracted twice with acetonitrile and decolored with graphite carbon powder. SalA and SalB were confirmed by liquid chromatography–tandem mass spectrometry in product ion scan mode, and quantified by high-performance liquid chromatography with UV detection (for SalA) and by mass spectrometry in single ion monitoring mode (for SalB). The SalA/SalB contents (μg/mg) were in the range of 3.2–5.0/0.10–0.17 in the dried leaf products and 4.1–38.9/0.26–2.42 in the “concentrated extract” products. These findings would be useful for analysis of S. divinorum-related products circulated in the drug market. 相似文献
74.
Céline Weyermann Ph.D. Claude Roux Ph.D. Christophe Champod Ph.D. 《Journal of forensic sciences》2011,56(1):102-108
Abstract: Determining the time since deposition of fingermarks may prove necessary to assess their relevance to criminal investigations. The crucial factor is the initial composition of fingermarks, because it represents the starting point of any aging model. This study mainly aimed to characterize the initial composition of fingerprints, which show a high variability between donors (inter‐variability), but also to investigate the variations among fingerprints from the same donor (intra‐variability). Solutions to reduce this initial variability using squalene and cholesterol as target compounds are proposed and should be further investigated. The influence of substrates was also evaluated, and the initial composition was observed to be larger on porous surface than nonporous surfaces. Preliminary aging of fingerprints over 30 days was finally studied on a porous and a nonporous substrate to evaluate the potential for dating of fingermarks. Squalene was observed to decrease in a faster rate on a nonporous substrate. 相似文献
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The organic peroxide explosive triacetone triperoxide (TATP) is regularly encountered by law enforcement agents in various stages of its production, storage, or usage. In a previous study, it has been demonstrated that isolated, rigorously purified, TATP may degrade to form a series of chlorinated acetones when directly treated with excess concentrated hydrochloric acid. The current study extends this work to examine whether this phenomenon may be measured during the more feasible scenario of aging of rudimentarily purified TATP contaminated with trace reaction mixture. It was demonstrated that solid-phase microextraction gas chromatography/mass spectrometry analyses of aged TATP that was synthesized utilizing hydrochloric acid catalyst may identify the presence of the degradation products chloroacetone and 1,1-dichloroacetone. Upon aging of TATP synthesized utilizing either sulfuric or nitric acid catalyst, no acid specific degradation products could be identified. These findings may be exploited by forensic chemists in the analyses of TATP samples. 相似文献
77.
Abstract: Indirect estimation methods of cocaine consumption may not reflect the real extent of cocaine use. Another approach is sewage epidemiology. This direct approach is based on analysis of a stable cocaine metabolite, benzoylecgonine (BE), in wastewater. Influent to the Lubbock (Texas) Water Reclamation Plant was sampled twice a week to assess weekly variations in estimates of cocaine consumption over a 5‐month period. BE was extracted from influent wastewater samples using solid phase extraction and analyzed using gas chromatography/mass spectrometry. Measured concentrations of BE were converted to cocaine equivalents; the estimated average daily consumption of cocaine during the study period was 1152 ± 147 g. Based on BE concentrations and sewage epidemiology, higher cocaine consumption was observed on weekends compared to weekdays (p < 0.0003). This method was effective in monitoring BE in wastewater and could be used to complement survey data in estimating cocaine use at a local level. 相似文献
78.
长期饮酒对急性中毒大鼠死后体液内MDMA再分布的影响 总被引:1,自引:0,他引:1
目的研究长期饮酒对急性中毒大鼠体液中亚甲基二氧甲基苯丙胺(MDMA)死后再分布的影响。方法 SD雄性大鼠360只,随机均分为A、B、C、D 4组;A、B组以白酒,C、D组以双蒸水为饮用液体,4周后各组按150mg/kg MDMA剂量灌胃,处死后分置于25℃、4℃条件下;以VARIAN CP-3800气相色谱仪分别检测处死时血乙醇含量和0~10d内体液样品中MDMA浓度。结果 0~10d不同条件下,大鼠血液、玻璃体液及尿液中MDMA的PMR浓度变化趋势均为先升高、后降低;各时间点A、B组和C、D组大鼠各体液样本MDMA浓度较0h均有显著性差异(P<0.05),各时间点A与C组、B与D组之间体液样本MDMA浓度有显著性差异(P<0.05);A与B组、C与D组之间体液样本MDMA浓度有显著性差异(P<0.05)。结论长期饮用乙醇会降低MDMA在体液样品中的再分布,其影响程度高低依次为血液、尿液及玻璃体液;低温也可减少体液中MDMA的再分布。 相似文献
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