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排序方式: 共有491条查询结果,搜索用时 15 毫秒
91.
目的 采用超高效液相色谱-四级杆飞行时间质谱(ultra-performance liquid chromatogra-phy/quadrupole time-of-flight-tandem mass spectrometry,UPLC-Q-TOF/MS)对复方守宫散中化学成分及其血中移行成分进行定性分析,为该制剂的...  相似文献   
92.
Testing for drugs in hair raises several difficulties. Among them is the interpretation of the final concentration(s). In a post‐mortem case, analyses revealed the presence of furosemide (12 ng/mL) in femoral blood, although it was not part of the victim's treatment. The prosecutor requested our laboratory to undertake an additional analysis in hair to obtain information about the use of furosemide. A specific method was therefore developed and validated to identify and quantify furosemide in hair by UHPLC‐MS/MS. After decontamination of 30 mg of hair, incubation in acidic condition, extraction with ethyl acetate, the samples were analyzed by UHPLC‐MS/MS. Furosemide was found in the victim's hair at 225 pg/mg. However, it was not possible to interpret this concentration due to the absence of data in the literature. Therefore, the authors performed a controlled study in two parts. In order to establish the basis of interpretation, several volunteers were tested (four after a single 20 mg administration and twenty‐four under daily treatment). The first part indicated that a single dose is not detectable in hair using our method. The second part demonstrated concentrations ranging from 5 to 1110 pg/mg with no correlation between dosage and hair concentrations. The decedent's hair result was interpreted as repeated exposures. In the case of furosemide analysis, hair can provide information about its presence but cannot give information about dosage or frequency of use.  相似文献   
93.
The Nanospec 10S microspectrophotometer has been used to produce reflectance spectra over the 380–900 nm range from coloured thin-layer chromatography spots. The method has been applied to extracted paint pigments and to dyes from other materials examined in forensic science.  相似文献   
94.
用GC/ECD方法分析海洛因中毒尿液吗啡代谢物   总被引:2,自引:2,他引:0  
目的 考查尿检材中海洛因的代谢物吗啡和单乙酰吗啡的液液萃取条件、三氟乙酰化和气相色谱电子捕获检测 (GC/ECD)条件。方法 以烯丙吗啡为内标 ,氯仿∶异丙醇 (9∶1)为液相萃取剂萃取尿中的吗啡和单乙酰吗啡 ,采用MBTFA衍生化 (三氟乙酰化 ) ,GC/ECD检测。结果 尿中加样相对回收率吗啡 89% ,单乙酰吗啡 75 % ,最小检测量吗啡 5 0ng ,单乙酰吗啡 10 0ng。通过实验兔的中毒实验 ,对尿检材进行了分析。 结论 所建立的萃取与检测方法分析海洛因中毒尿检材中的吗啡准确、灵敏 ,可用于海洛因的吸毒检验  相似文献   
95.
目的建立人血、尿中地芬尼多的气相色谱快速分析方法。方法用氯仿提取血、尿中的地芬尼多,采用气相色谱法进行定性、定量分析。以正常人血浆、尿液为空白样本,分别添加标准地芬尼多及SKF525(内标物)对方法进行考察和优化,并对1例大剂量误服地芬尼多中毒者体液浓度进行快速测定和检测。结果所建方法分析血、尿中地芬尼多的线性范围均为5.0~200.0μg/mL;最低检测限均为1.0μg/mL(S/N≥3);日内、日间精密度RSD≤5.6%(n=5);回收率:血≤(106.23±2.05)%;尿≤(104.19±5.51)%。结论该分析方法操作便捷、实用,适用于地芬尼多的临床血药浓度快速监测和法医毒物鉴定。  相似文献   
96.
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   
97.
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   
98.
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   
99.
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   
100.
随着大麻走私的日益猖獗,对大麻进行快速准确的定性定量分析,为司法部门量刑提供准确可靠的依据显得尤为重要。本文对大麻的化学成分、检材种类、滥用方式进行介绍,并对气相色谱分析方法中涉及的检材提取方法、内标物、色谱柱和质谱图等进行综述。  相似文献   
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