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61.
A case of suspected acute and lethal intoxication caused by colchicine has been reported. The woman was hospitalized after her suspicion of suicidal poisoning by a rare autumn crocus (Colchicum autumnale). Suspected colchicine poisoning was confirmed using a novel UHPLC method with a modern reversed‐phase stationary phase with a sub 2‐micron superficial porous particle size combined with a QTOF mass spectrometer. Sample preparation procedure included the addition of propiverine as internal standard, protein precipitation using methanol and solid phase extraction. High‐resolution MS only and targeted MS/MS modes are reported for the qualitative analysis and screening of other potential drugs of abuse in blood samples. All Ion MS mode was used for quantitative determination of colchicine afterward. The concentration of colchicine in the blood sample was approximately 41 ng/mL, and more than 200 μg/mL of the plant extract used for the suicide.  相似文献   
62.
Fentanyl deaths have increased with availability of transdermal patches. Interpretation of postmortem fentanyl levels may be complicated by postmortem redistribution and absorption of fentanyl from a patch. We applied an unused 100‐μg/h fentanyl patch onto the lower abdomen of a decedent with no premortem fentanyl exposure. Ocular fluid, blood, and urine were collected prior to placement, and the decedent was refrigerated for 23 h. Prior to the autopsy, urine, subcutaneous tissue under the patch, and samples from the same anatomic sites were obtained. We observed no fentanyl in any postpatch placement samples (LOD: 0.1 ng/mL for blood and vitreous fluid, 1.0 ng/mL urine, 2.0 ng/g for tissues). Although we observed no postmortem absorption of fentanyl, this was only a single case; therefore, we recommend that patches be removed after receipt of a cadaver before initiation of an autopsy, with the location of removed patch documented.  相似文献   
63.
Objective To develop a liquid chromatography-tandem mass spectrometry(LC-MS/MS) screening method for 45 poisonous alkaloids in blood. Methods Identification was based on the compound’s retention time and two precursor-to-production transitions. The method involved a liquid-liquid extraction(LLE) followed by LC-MS/MS with multiple-reaction monitoring(MRM). When 1 m L of blood was extracted with diethyl ether at p H=9.2 with SKF525 Aas the internal standard, the target compounds were analyzed with LC-MS/MS in the positive ionization mode. Results The target alkaloids had good linearity(r>0.995 1), both the intra-day precision and inter-day precision being less than 14.77%. The limits of detection ranged from 0.05 to 25 ng/m L in blood. Conclusion The method is selective and sensitive in detecting poisonous alkaloids with a total running time of 12 minutes; therefore it was successfully applied to some actual cases of suspected alkaloids poisoning.  相似文献   
64.
犯罪嫌疑人遗留在各种光滑平面上的新鲜或陈旧性汗液指印,由于潜在指印与背景之间的反射亮度差很小,加之背景颜色的干扰,一般光照条件下拍摄相当困难。运用定向反射照相法,能加强纹线与背景的亮度差异,消除背景颜色的干扰,取得较好的拍摄效果。  相似文献   
65.
目的研究采用中空纤维膜液相微萃取(hollowfiber liquid phase microextraction,HF-LPME)法提取水和生物体液中的哌替啶,氯胺酮,曲马多。方法样品调节至pH11.5和盐饱和,磁力搅拌器转速为600转/min,内标为盐酸萘福泮,取4μl甲苯,注入到聚偏氟乙烯中空纤维膜中,萃取20min,抽回1μl甲苯进入GC中进行分析。结果血浆、尿、水相关系数R2:哌替啶分别为0.9935、0.9981、0.9997,氯胺酮分别为0.9906、0.9913、0.9927,曲马多分别为0.9741、0.9913、0.9970;检测限:水、尿中哌替啶、氯胺酮、曲马多均为0.01μg/ml,血浆中哌替啶、氯胺酮、曲马多均为0.05μg/ml;血浆、尿、水日内RSD:哌替啶分别为13.0%、7.3%、4.6%,氯胺酮分别为15.1%、13.6%、1.4%,曲马多分别为3.7%、4.3%、9.0%;血浆、尿、水日间RSD:哌替啶分别为15.1%、13.5%、12.2%,氯胺酮分别为12.3%、5.3%、6.0%,曲马多分别为7.1%、15.5%、11.9%;血浆、尿、水相对回收率:哌替啶分别为109.80%、93.49%、97.57%,氯胺酮分别为91.09%、101.80%、100.40%,曲马多分别为106.40%、92.94%、113.32%。结论中空纤维膜液相微萃取用于水和生物体液中的哌替啶,氯胺酮,曲马多的分析,所需有机溶剂少,避免残留和交叉污染,集萃取,富集,进样于一步完成,简单,高效,实用。  相似文献   
66.
The illegal use of formalin (commercial formaldehyde) in cosmetic products harms the health of individuals exposed to this substance. Over the last years, the commercial availability of these products, especially those containing irregular dosage of formaldehyde, has increased in Brazil. This work analyzes some products for hair treatment available in the Brazilian market and verifies their safety. The adopted analytical methodology involved sample derivatization with 2,4‐dinitrophenylhydrazine, followed by high‐performance liquid chromatography with ultraviolet detection (UV–VIS) at λ = 365 nm. The limit of quantification is 2.5 × 10?3% w/w, and the recovery tests were around 93%. Some of the samples contained high and illegal formaldehyde levels ranging from 9% to 19% (w/w) and others presented suitable concentrations of the analyte. On the basis of the results, this work discusses the efficiency and practicality of this analytical method for forensic purposes.  相似文献   
67.
Opium is the raw material for the production of heroin, and the characterization of opium seizures through laboratory analysis is a valuable tool for law enforcement agencies to trace clandestine opium production and trafficking. In this work, a method for opium profiling based on the relative content of five principal and 14 minor opium alkaloids was developed and validated. UPLC‐Q‐TOF was adopted in alkaloid analysis for its high selectivity and sensitivity, which facilitated the sample preparation and testing. The authentic sample set consisted of 100 “Myanmar” and 45 “Afghanistan” opium seizures; based on the data set of the 19 alkaloid variables in them, a partial least squares discriminant analysis classification model was successfully achieved. Minor alkaloids were found to be vitally important for opium profiling, although combined use of both principal and minor alkaloids resulted in the best geographical classification result. The developed method realized a simple and accurate way to differentiate opium from Myanmar and Afghanistan, which may find wide application in forensic laboratories.  相似文献   
68.
Caffeine is the most widely consumed psychoactive agent worldwide and has the potential for abuse, but studies monitoring caffeine abuse in China are scarce. This study aims to estimate the prevalence of caffeine abuse in northwest China and investigate the correlation between caffeine and other drugs in hair and nails using an ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Fingernail clippings were collected from 376 participants in northwest China to detect caffeine and 13 other illicit psychoactive drugs and their metabolites. Paired hair and nail samples were collected from 39 participants to investigate the correlation between caffeine and other drugs in hair and nails. The samples were decontaminated, pulverized, and extracted by a high-throughput nail sample preparation method and analyzed by UPLC-MS/MS. The results showed a risk of caffeine abuse in northwest China, with concentrations ranging from 0.43 to 10.6 ng/mg for healthy volunteers, 0.49–246 ng/mg for caffeine abusers, and 0.25–363 ng/mg for drug addicts in community rehabilitation centers. Caffeine was detected together with other illicit psychoactive drugs and their metabolites. Furthermore, positive detection correlations were found between hair and nail samples. This study provides a current perspective on caffeine abuse in northwest China and demonstrates the practical use of UPLC-MS/MS for the simultaneous detection of caffeine and 13 illicit psychoactive drugs and their metabolites in hair and nails. The results highlight the potential of nails as a supplementary matrix when hair samples are unavailable and emphasize the need for handling caffeine carefully given its potential for abuse.  相似文献   
69.
A new, fast, and ultra-sensitive headspace sampling method using the Capillary Microextraction of Volatiles (CMV) device is demonstrated for the analysis of ignitable liquid residues (ILRs) in fire debris. This headspace sampling method involves the use of a heated can (60°C) to aid in the recovery of volatile organic compounds (VOCs) from medium and heavy petroleum distillates. Our group has previously reported the utility of CMV to extract gasoline at ambient temperature in less than 5 min in the field. This work evaluates the recovery and analysis of low mass loadings (tens of ng) of VOCs from charcoal lighter fluid, kerosene, and diesel fuel. Nonane, decane, undecane, tridecane, tetradecane, and pentadecane were selected for evaluation of recovery to represent these ILR classes. The face-down heated can headspace sampling technique was compared to the previously reported, non-heated, paper cup headspace sampling technique. Mass recovery improvements of 50%–200% for five of the six target compounds in diesel fuel were achieved compared to the non-heated sampling method. The average relative standard deviation (reported as % RSD) between the replicate trials decreased from an average of 28% to 6% when using the heated can method. Ignitable liquids were spiked onto burned debris in a live burn exercise and sampled using the heated can and paper cup headspace sampling techniques. The heated sampling technique reported here, for the first time, demonstrates an effective extraction method that when coupled to a portable GC–MS instrument allows for a sampling and analysis protocol in the field in less than 30 min.  相似文献   
70.
The effect of substrate interferences from high‐density polyethylene (HDPE) on the ability to associate an ignitable liquid residue with the corresponding liquid standard, using statistical procedures, is demonstrated. Gasoline, kerosene, and lighter fluid, at three different evaporation levels, were spiked onto HDPE and subsequently burned to generate simulated ignitable liquid residues (ILRs). Samples were extracted using a passive headspace procedure and analyzed by gas chromatography–mass spectrometry. The total ion chromatograms were subjected to data pretreatment procedures prior to principal components analysis and Pearson product moment correlation. Using the combination of these statistical procedures, simulated ILRs were successfully associated with the corresponding liquid type, despite the presence of compounds inherent to the HDPE substrate, as well as those resulting from pyrolysis of the substrate.  相似文献   
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