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171.
目的基于变性高效液相色谱技术,建立一种不需测序和杂交的新的mtDNA控制区多态性分析系统。方法mtDNA控制区序列(包括HVⅠ,HVⅡ和HVⅢ)被分为4个扩增片段,采用配对分析突变检测模式进行DHPLC分析。对DHPLC检测条件(包括柱温和洗脱梯度等)进行优化。对100个不同类型差异序列的组合配对以检验该方法的检测效力。结果10组序列相同的样本配对DHPLC图谱均只显示1个样品峰。对序列相差1个碱基~7个碱基、插入(/缺失)1个碱基、插入(/缺失)2个碱基等类型的90个扩增片段组合,用DHPLC进行分析,均得到≥2个样本峰的DHPLC图谱,序列差异检出率达100%。该技术可检测的异质性DNA成分的最小百分含量为10%。结论DHPLC-mtDNA控制区多态性分析系统快速、经济和实用,在检测mtDNA异质性方面较直接测序更灵敏。 相似文献
172.
甲醛处理后人脊髓中的利多卡因和布比卡因的同时测定 总被引:2,自引:0,他引:2
目的建立经甲醛防腐处理后人脊髓中利多卡因和布比卡因同时定量测定的HPLC分析法,以满足法医学鉴定的需要。方法以空白人脊髓经甲醛防腐处理后添加标准利多卡因和布比卡因,对样品的前处理方法及仪器测试条件、方法的线性范围、检测限、精密度、回收率进行系统考察。结果所建方法中两药物的线性范围为0.5~10.0ug.g-1(利多卡因r=0.9999;Bupivacaine r=0.9998),检测限利多卡因为15ng布比卡因为20ng,日内、日间分析的相对标准偏差均在4.3%以内,加样回收率在97.3%~100.3%之间。结论经甲醛防腐处理后的脊髓可同时进行利多卡因和布比卡因定量测定。所建方法准确、实用,适用于法医学鉴定及相关研究。 相似文献
173.
Abstract: A 15‐year‐old male orally consumed an unknown but fatal amount of sustained release hydromorphone. He was naïve to opioid use. No other drugs or alcohol were involved. The cause of death was acute aspiration‐related bronchopneumonia, secondary to hydromorphone ingestion; the manner of death was accidental. Hydromorphone and hydromorphone‐3‐glucuronide were quantified in postmortem fluids by tandem liquid chromatography–mass spectrometry. The hydromorphone concentrations in the peripheral blood, urine, and vitreous humor were 57, 4460, and 31 ng/mL, respectively. The hydromorphone‐3‐glucuronide concentrations in the corresponding three fluids were 459, 36,400, and 40 ng/mL. Hydromorphone‐3‐glucuronide accumulation probably did not contribute significantly to the opiate toxicity. The proposed minimum lethal hydromorphone blood concentration in the nontolerant user is in the vicinity of 60 ng/mL. 相似文献
174.
Andrew J. Schweighardt Ph.D. Amanda Battaglia M.S. Margaret M. Wallace Ph.D. 《Journal of forensic sciences》2014,59(1):15-33
A bead‐based liquid hybridization assay, Luminex® 100?, was used to identify four pathogenic bacteria, Bacillus anthracis, Clostridium botulinum, Francisella tularensis subsp. tularensis, and Yersinia pestis, and several close relatives. Hybridization between PCR‐amplified target sequences and probe sequences (located within the 23S ribosomal RNA gene rrl and the genes related to the toxicity of each bacterium) was detected in single‐probe or multiple‐probe assays, depending on the organism. The lower limits of detection (LLDs) for the probes ranged from 0.1 to 10 ng. Sensitivity was improved using lambda exonuclease to digest the noncomplementary target strand. All contributors in 33 binary, ternary, and quaternary mixtures in which all components were present in a 1:1 ratio were identified with an 80% success rate. Twenty‐eight binary mixtures in which the two components were combined in various ratios were further studied. All target sequences were detected, even when the minor component was overshadowed by a tenfold excess of the major component. 相似文献
175.
Sarah Kerrigan Ph.D. Ashley Mott M.S. Breanna Jatzlau M.S. Francisco Ortiz M.S. Laura Perrella M.S. Sarah Martin M.S. Kelsie Bryand M.S. 《Journal of forensic sciences》2014,59(1):175-183
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
176.
Meredith D. Murrell M.S. Dianne A. Cruz M.S. Martin A. Javors Ph.D. Peter M. Thompson M.D. 《Journal of forensic sciences》2014,59(3):683-689
Venlafaxine (VEN) and its metabolite O‐desmethylvenlafaxine (ODV) inhibit reuptake of serotonin and norepinephrine. This study examines whether VEN is differentially distributed in postmortem brain and examines relationships between brain and femoral blood concentrations from donors prescribed VEN for treatment of depression. Using high‐pressure liquid chromatography‐ultraviolet detection, VEN and ODV concentrations were measured in temporal, occipital, and cerebellar cortex of six postmortem brains. The ODV/VEN ratio was calculated as a relative measure of drug metabolism within each region where higher ratios indicated a greater conversion of VEN to ODV. Compared to the other regions examined, the cerebellum showed decreased VEN (p = 0.056), ODV (p = 0.006), and ODV/VEN (p = 0.027) ratios. In parts per million, VEN was higher in temporal and occipital cortex, but not cerebellum, as compared to femoral blood concentration. These observations suggest that VEN and ODV are differentially distributed in the brain, and metabolism of VEN to ODV may vary across brain regions. 相似文献
177.
Jérémy Carlier M.Sc. Emmanuel Escard M.D. Michel Péoc'h M.D. Ph.D. Baptiste Boyer M.D. Ludovic Romeuf M.Sc. Thierry Faict M.D. Ph.D. Jérôme Guitton Pharm.D. Ph.D. Yvan Gaillard Pharm.D. Ph.D. 《Journal of forensic sciences》2014,59(3):859-864
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
178.
目的建立了鸦片中吗啡、可待因、蒂巴因、罂粟碱、那可汀5种常量生物碱和牛心果碱、劳丹宁、劳丹素等12种痕量生物碱同时分离鉴定的超高效液相色谱-高分辨四极杆飞行时间串联质谱(UPLC/Q-TOF)方法。方法采用Agilent Eclipse Plus C18RRHD(2.1 mm×100 mm,1.8μm)色谱柱,以10 mM甲酸铵溶液和乙腈体系梯度洗脱,使用ESI离子源,正离子模式下采集数据。结果借助UPLC的快速分离和Q-TOF-MS测定的精确分子量和二级碎片信息,实现了17种生物碱的检测。应用SIMCA-P软件对78份国产鸦片和200份缅甸产鸦片进行偏最小二乘法判别分析(partial least squaresdiscriminate analysis,PLS-DA),比较不同地区鸦片样品中生物碱的差异,建立了区分国产鸦片和缅甸产鸦片的判别方法。结论所建立的方法用于鸦片样品中常量和痕量生物碱的检测及鸦片样品的产地判别,具有快速、高效、灵敏、准确的特点。 相似文献
179.
Munchelou M. Gomonit BS Britni Skillman PhD Madeleine J. Swortwood PhD 《Journal of forensic sciences》2024,69(2):678-687
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
180.