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351.
In March 2009, the body of a 51‐year‐old man was found in the boot of his car. The body had been frozen before being dismembered at the abdomen. The autopsy failed to determine the cause of death. Systematic toxicological analyses of the victim's peripheral blood and urine showed the presence of atropine, a powerful anticholinergic. Atropine was therefore specifically detected and quantified throughout the victim's biologic samples by HPLC‐MS² in the biologic fluids and UHPLC‐MS² in the hair. The atropine concentrations were 887 ng/mL in the cardiac blood, 489 ng/mL in the peripheral blood, 6693 ng/mL in the gastric contents (1.1 μg), 6753 ng/mL in the urine, and 2290 pg/mg in the hair. The blood concentrations measured in the decedent were consistent with an overdose of atropine, which was determined as the cause of death. The manner of death was a homicide with criminal intent.  相似文献   
352.
目的 调查浙江宣城地区汉族人群5000例无关个体18个STR基因座多态性分布.方法 应用AmpFlSTR Identifiler荧光标记复合扩增系统检测,统计计算群体遗传学参数.结果 18个STR基因座的基因型分布均符合Hardy-Weinberg平衡(P>0.05),共检出270个等位基因,频率在0.0001~0.5260之间,共有1289种基因型,在13个基因座上检出共44个微变异等位基因.18个基因座的杂合度观察值(Ho)在0.6238~0.9120之间,杂合度理论值(He)在0.6961~0.9601之间,多态信息含量(PIC)在0.5578~0.9126之间,累计个人识别率(TDP)为0.999 999 999 999 999 999 999 953,三联体累计非父排除概率(CPE)为0.999 999 993487 306,二联体累计非父排除率(CPE*)为0.985819169.结论 本文调查结果与以往文献报道的不同地区民族的人群等位基因频率资料有一定程度的差异性.上述18个STR基因座适用于宣城地区汉族群体各类案件的法医学个体识别和亲权鉴定.  相似文献   
353.
《Science & justice》2020,60(3):253-262
Papaver somniferum, commonly known as opium poppy, is the source of natural opiates, which are used as analgesics or as precursors in the creation of semi-synthetic opioids such as heroin. An increase in opioid addiction in the United States has resulted in high rates of illicit opioid use and overdoses. It has recently been shown that P. somniferum DNA suitable for genetic analysis can be recovered from heroin samples. The development of a comprehensive genetic individualization tool for opium poppy could serve to link cases and strengthen programs such as the Drug Enforcement Administration’s (DEA) Heroin Signature Program, which seeks to combat rising opioid use.The purpose of this study was to develop a quantitative real-time PCR (qPCR) method for the quantification of opium poppy DNA, compare three commercial DNA extraction kits for their ability to isolate DNA from poppy seeds, and evaluate nineteen opium poppy short tandem repeat (STR) markers for their use in a forensic identification panel. Such a panel could be used for individualizing samples and determining the geographic origin in heroin or poppy seed tea cases. The qPCR method was proven to be reproducible and reliable, specific for P. somniferum, and sensitive enough for forensic case-type samples. Of the three kits tested, the nexttec™ one-step DNA Isolation Kit for Plants was the optimal method and facilitated rapid extraction of DNA from poppy seeds. The majority of evaluated STR primer sets were unreliable or had low discriminatory power, limiting their use for individualization of poppy samples. A six-locus STR multiplex was developed and evaluated according to Scientific Working Group on DNA Analysis Methods (SWGDAM) and International Society of Forensic Genetics (ISFG) guidelines, including the use of a sequenced allelic ladder. The multiplex was found to have low discriminatory power, with greater than two-thirds of samples analyzed having just two different genotypes. The multiplex was determined to be unsuitable for individualization; however, a genotype map was developed as a proof of concept that these markers may be useful for determining the biogeographical origin of samples. Searching the poppy genome for new STR markers and developing new primer sets may be necessary for the creation of a powerful genetic tool for the individualization of P. somniferum.  相似文献   
354.
目的应用相对和绝对定量同位素标记结合液相色谱-串联质谱法(isobaric tag for relative and absolute quantification-liquid chromatograph-mass spectrometer/mass spectrometer,iTRAQ-LC-MS/MS)筛选SD大鼠弥漫性轴索损伤(diffuse axonal injury,DAI)后脑组织差异表达的蛋白质,寻找诊断DAI的潜在生物标志物。方法参照Marmarou法建立DAI动物模型,分为空白对照组(n=4)、假打击组(n=4)和打击致死组(n=4),采用iTRAQ-LC-MS/MS技术对大鼠脑组织蛋白质进行检测,并对检测结果进行生物信息学分析及验证,筛选出差异表达的蛋白质。结果定量检测出2016种蛋白质,生物信息学分析显示其在细胞中分布广泛、功能多样,并且参与了多种生物过程,16种蛋白质在打击致死组具有差异表达,包括1种表达上调蛋白质和15种下调蛋白质;Western印迹法验证了iTRAQ-LC-MS/MS的结果。结论 iTRAQ-LC-MS/MS的检测技术筛选出大鼠DAI后脑组织中多个差异表达的蛋白质,不仅为深入探讨DAI后轴索损伤的发病机制提供了研究方向,也为DAI的诊断提供了潜在生物标志物。  相似文献   
355.
356.
A common problem in forensic DNA typing is PCR inhibition resulting in allele dropout and peak imbalance. In this paper, we have utilized the Plexor® real‐time PCR quantification kit to evaluate PCR inhibition. This is performed by adding increasing concentrations of various inhibitors and evaluating changes in melt curves and PCR amplification efficiencies. Inhibitors examined included calcium, humic acid, collagen, phenol, tannic acid, hematin, melanin, urea, bile salts, EDTA, and guanidinium thiocyanate. Results were plotted and modeled using mathematical simulations. In general, we found that PCR inhibitors that bind DNA affect melt curves and CT takeoff points while those that affect the Taq polymerase tend to affect the slope of the amplification curve. Mixed mode effects were also visible. Quantitative PCR results were then compared with subsequent STR amplification using the PowerPlex® 16 HS System. The overall results demonstrate that real‐time PCR can be an effective method to evaluate PCR inhibition and predict its effects on subsequent STR amplifications.  相似文献   
357.
目的建立24个基因座的复合扩增系统,并对其性能指标进行评价。方法选择24个基因座(包含D8S1179、D5S818、D2S1338、D18S51、D6S1043、D2S441、D3S1358、vWA、D19S433、D16S539、CSF1PO、Penta D、D22S1045、D13S317、D1S1656、D7S820、TPOX、Penta E、D10S1248、TH01、D12S391、D21S11、FGA等23个STR基因座及1个Amelogenin基因座);合成引物,上游端标记荧光染料;收集DNA数据库建库血痕及口腔拭子样本及相关11种动物样本,采用本文方法进行复合扩增;并对方法的准确性、灵敏度、稳定性、种属特异性、检材适用性、混合样本的检验等系统性能指标进行验证。结果本文复合扩增系统对最长保存9年的各种血痕检材完整分型成功率为100%,且均衡性良好,无非特异性扩增,口腔拭子的成功率为97.8%,灵敏度达125pg,对含有抑制剂样本,在血红素浓度≤600μmol/L,腐殖酸浓度≤50ng/μL时检出效果稳定,种属特异性好。结论本文24个基因座复合扩增系统在DNA数据库建设中具有较好的应用价值。  相似文献   
358.
观察福建地区亲权鉴定中常用STR基因座突变现象,分析福建汉族人群遗传突变率和一些常用位点的突变情况。在3702例亲权关系鉴定的案例中,观察到79例发生基因突变,D8S1179、D21S11、D7S820等15个位点发生突变。  相似文献   
359.
There has been burgeoning interest in psilocybin-use for the treatment of various neurological and neurodegenerative diseases. Psilocybin is mistakenly perceived as the principal pharmacologically active compound due to its high concentrations found in magic mushrooms; however, it is the prodrug of psilocin. Despite the expanding body of clinical research seeking to understand the pharmacodynamic/pharmacokinetic properties of psilocin, and its role in inducing dramatic changes to cognitive function, there has not been a corresponding increase in the development of sensitive analytical methods that can quantify psilocin in different biological fluids. Existing analytical methods have been developed using plasma, serum, and urine as the matrix of choice, but with the unknown blood-to-plasma ratio of psilocin, any pharmacokinetic conclusions drawn solely on plasma data may be misleading. Thus, the main objective of this study is to develop the first analytical method that utilizes SPE and LC–MS/MS to quantify psilocin in human whole blood. The SPE procedure yielded a high recovery efficiency (≥89%) with minimal matrix effects. The method was validated according to ANSI/ASB 036 guidelines. Linearity was between 0.7–200 ng/mL and encompassed previously reported ranges found in plasma/serum. Bias, within- and between-run precision for all quality controls met ANSI/ASB 036 acceptability criteria. Endogenous/exogenous interferences and carryover were negligible. Psilocin stability was assessed at 4°C over 48 h and was considered stable. Although a proof-of-concept study will need to be performed to characterize the method, this analytical workflow was able to detect and quantify psilocin in human whole blood at low limits of quantification.  相似文献   
360.
Designer psychostimulants are known by recreational drug users to produce a complex array of adrenergic and hallucinogenic effects. Many of these drugs are not targeted during routine toxicology testing and as a consequence, they are rarely reported. The purpose of this study was to develop a procedure for the detection of 15 psychostimulants in urine using liquid chromatography–tandem mass spectrometry (LC‐MS/MS), specifically 2,5‐dimethoxy‐4‐bromophenethylamine (2C‐B), 2,5‐dimethoxy‐4‐chlorophenethylamine (2C‐C), 2,5‐dimethoxy‐4‐methylphenethylamine (2C‐D), 2,5‐dimethoxy‐4‐ethylphenethylamine (2C‐E), 2,5‐dimethoxyphenethylamine (2C‐H), 2,5‐dimethoxy‐4‐iodophenethylamine (2C‐I), 2,5‐dimethoxy‐4‐ethylthiophenethylamine (2C‐T‐2), 2,5‐dimethoxy‐4‐isopropylthiophenethylamine (2C‐T‐4), 2,5‐dimethoxy‐4‐propylthiophenethylamine (2C‐T‐7), 2,5‐dimethoxy‐4‐bromoamphetamine (DOB), 2,5‐dimethoxy‐4‐chloroamphetamine (DOC), 2,5‐dimethoxy‐4‐ethylamphetamine (DOET), 2,5‐dimethoxy‐4‐iodoamphetamine (DOI), 2,5‐dimethoxy‐4‐methylamphetamine (DOM), and 4‐methylthioamphetamine (4‐MTA). Analytical recoveries using solid‐phase extraction were 64–92% and the limit of detection was 0.5 ng/mL for all drugs except 2C‐B (1 ng/mL). The assay was evaluated in terms of analytical recovery, precision, accuracy, linearity, matrix effect, and interferences. The technique allows for the simultaneous detection of 15 psychostimulants at sub‐ng/mL concentrations.  相似文献   
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