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21.
The present paper describes a sensitive method developed in our laboratory for the simultaneous analysis of opiates (morphine, codeine and monoacetylmorphine), cocainics (cocaine and benzoylecgonine) and cannabinoids (Δ9-tetrahydrocannabinol and 11-nor-Δ9-tetrahydrocannabinol-9-carboxylic acid) in hair samples. After decontaminating the sample with dichloromethane, two consecutive hydrolyses were performed in order to achieve the best conditions for extracting the three kinds of drugs from the protein matrix. First the opiate and cocainic compounds were extracted by means of a soft acidic hydrolysis with 0.1 N HCl at 50 °C overnight and organic solvent extraction at pH 9.2. The cannabinoids need a stronger basic hydrolysis with 11.8 N KOH for 10 min at laboratory temperature. After adding maleic acid, the cannabinoids were extracted with an organic solvent. The derivatization was carried out with heptafluorobutyric anhydride and hexafluoropropanol. Calibration curves were linear between 0.5–100 ng/mg of hair. Recovery and reproducibility were assured. The quantification limits ranged between 0.04–0.26 ng/mg of hair. Seventy hair samples from known drug abusers were cut into 1-cm segments and analyzed by this method. The ranges of measured concentrations (ng/mg) were 0.31–89 for cocaine, 0.1–5.76 for benzoylecgonine, 0.34–45.79 for morphine, 0.45–39.59 for codeine, 0.09–48.18 for monoacetylmorphine, 0.06–7.63 for THC and 0.06–3.87 for THC---COOH. The results of sectional analyses agreed with the self reported drug histories. The usefulness of this method is in assessing earlier drug consumption, and also at the same time obtaining a chronological profile of the consumption of these three types of drugs.  相似文献   
22.
Phenobarbital analysis was performed in vertex hair of patients by gas chromatography mass spectrometry (GC/MS). After washing with dichloromethane, about 250 mg were ground to dust in a ball mill. A 50-mg sample was stirred mechanically for 10 min with 3 ml of NH4Cl/HCl buffer (pH 2.0) containing phenobarbital D5. A solid phase extraction was performed (extrelut Merck) and elution was achieved with chloroform/isopropanol/n-heptane (50:17:33; v/v). A full scan (40–240 uma) acquisition was realized by GC/MS with an ion trap (ITD 700 Finnigan) using a DB5-MS chromatographic column. Quantification was achieved by integrating dominants ions (phenobarbital, 204; phenobarbital D5, 209). Compared to serum, hair concentrates phenobarbital during anti-epileptic therapy (average value 36.4 ng/mg, n = 40 vs. 18.7 mg/l, n = 23). A group correlation exists between phenobarbital in hair and phenobarbital in serum, and between phenobarbital in hair and clinic observation in some typical cases. Phenobarbital in hair yields good information over a long period, especially when blood collection has not been made, when clinical disorders are observed on long-term therapeutic observance.  相似文献   
23.
Active cocaine use results in sequestration of parent drug in hair. In addition, hair has unique physicochemical properties that permit absorption of cocaine from the environment. When hair is tested for evidence of cocaine, it is important to consider whether the positive test resulted from active drug use or environmental contamination. In a series of laboratory experiments, it was found that exposure of ‘cut’ hair to cocaine vapor (‘crack’ smoke) and to aqueous solutions of cocaine hydrochloride resulted in significant contamination of hair samples. Similar results were obtained with two subjects who were exposed to cocaine vapor in an unventilated room. The amount of contamination adsorbed by hair depended upon both time and extent of exposure. Washing the hair samples with methanol removed >70% of the cocaine contaminant after cocaine vapor exposure, but was less effective (<50%) following contamination with aqueous cocaine. Shampoo treatment cycles (overnight soaking) progressively removed increasing amounts of cocaine from the contaminated hair, but residual cocaine remained after 10 cycles. Studies were also performed to determine the usefulness of benzoylecgonine as a marker of active cocaine administration. Small amounts of benzoylecgonine (ca. 1 ng/mg) were formed in hair as a result of environmental contamination with cocaine. Also, it was found that benzoylecgonine could be adsorbed from illicit cocaine contaminated with benzoylecgonine. It was concluded that positive hair test results should be interpreted cautiously due to the possibility of environmental contamination from cocaine and related constituents.  相似文献   
24.
Two direct ethanol metabolites, namely ethyl glucuronide (EtG) and cocaethylene (CE), in the hair of cocaine (COC) users were compared in this study. Hair samples (n=68) were submitted to the determination of EtG (by liquid chromatography-electrospray-tandem mass spectrometry) and of COC and metabolites, including CE (by gas chromatography-mass spectrometry). Quantitative and qualitative results were compared. No quantitative correlation was found between EtG and CE, as well as between EtG and the cocaethylene concentration divided by the concentration of COC and its metabolites (benzoylecgonine and ecgonine methylester, as COC equivalents). Nevertheless, many factors are supposed to affect the amount of the two substances incorporated in the hair matrix, such as the subject's habits in ethanol and COC use, genetic variability in the metabolism of both substances, and the different chemical and physical properties of EtG and CE. When establishing a cut-off of 4 pg/mg for EtG and of 200 pg/mg for CE, 47 samples tested positive for EtG and 41 samples tested positive for CE; 12 samples out of the 47 EtG-positives tested negative for CE (25%), whereas 6 samples out of the 41 CE-positives tested negative for EtG (15%). According to these data, EtG appears to be a more sensitive and specific marker of non-moderate alcohol users than CE.  相似文献   
25.
To validate information on cannabis use, we investigated human hair and pubic hair for cannabinoids (THC and THC-COOH) by gas chromatography/mass spectrometry. Samples (100 mg approximately) were decontaminated with methylene chloride, then pulverized and dissolved in 1 ml 1 N NaOH for 10 min at 95 °C in the presence of 200 ng of deuterated standards. After cooling, samples were extracted by n-hexane/ethyl acetate after acidification with acetic acid. After derivatization of the dry extract by PFPA/PFP-OH, the drugs were separated on a 30-m capillary column and detected using selected-ion monitoring (m/z 377 and 459 for THC and THC-COOH, respectively). Forty-three hair samples were obtained from fatal heroin overdose cases. Among them, 35% tested positive for cannabinoids. Hair concentrations ranged from 0.26 to 2.17 ng/mg (mean, 0.74 ng/mg) and 0.07 to 0.33 ng/mg (mean, 0.16 ng/mg) of THC and THC-COOH, respectively. As is generally the case for other drugs detected in hair, metabolite concentration was always lower when compared to the parent drug concentration. In pubic hair, THC concentrations ranged from 0.34 to 3.91 ng/mg (mean, 1.35 ng/mg) and THC-COOH concentrations from 0.07 to 0.83 ng/mg (mean, 0.28 ng/mg). In most cases, the highest cannabinoid concentration was found in pubic hair, suggesting that this sample may be the more suitable for cannabis testing.  相似文献   
26.
Testing human hair for drugs of abuse is a relatively new technique which requires control before being fully accepted in Justice applications. A consensus procedure was recently proposed to the four French Laboratories performing hair analysis for opiates and cocaine. Results of two independent controls have shown that the laboratories have performed very well quantitatively, using the recommended method. In order to compare these results with those obtained by other procedures, one sample was sent to 15 laboratories concerned with the analysis of human hair for drugs of abuse in Germany, Italy, Spain, and United States. Results from this study have indicated that the French recommended method is in accordance with the general procedures.  相似文献   
27.
6-Monoacetylmorphine (6-MAM) is a good indicator for the intake of heroin and can be detected in blood, urine and hair of heroin users. A new radioimmunoassay (RIA) designed specifically for 6-monoacetylmorphine (6-MAM) was tested for its usefulness for the quantitation of the drug in urine, serum and hair. Its cross-reactivity with heroin and its metabolites, and related compounds was also determined. Eighty-nine hair, six serum and 25 urine samples where 6-MAM had been previously identified by GC/MS were analysed for 6-MAM with the new RIA kit. A good correlation existed between the GC/MS and RIA results for the hair samples. However, the amount of 6-MAM found in serum and urine differed considerably between the two methods. This difference could be explained by the cross-reactivity of the antibody with morphine and morphine-6-glucuronide, which are present in much larger amounts in serum and urine, than in hair. To evaluate a new rationalisation procedure, some hair samples were split into two portions after incubation. One part was analyzed for 6-MAM by RIA, and the other portion by GC/MS.  相似文献   
28.
毛发常见机械性损伤形态的环境扫描电镜研究   总被引:2,自引:0,他引:2  
目的建立环境扫描电镜(ESEM)法推断毛发致伤物种类的新方法。方法应用ESEM观察分析不同锐器、钝器及致伤方式形成的毛发机械性损伤的微观形态特征。结果毛发锐器、钝器损伤的表面微观特征存在显著差异,同种类型致伤工具,其锋利程度、作用方式不同时,其损伤特征也明显不同。结论ESEM法能够真实、自然反映毛发机械性损伤表面微观特征,可应用于推断毛发致伤物种类。  相似文献   
29.
This work presents the validation of a new immunological assay, the One-Step™ enzyme-linked immunosorbent assay (ELISA) tests from International Diagnostic Systems Corp. for the screening of drugs of abuse (cannabis, amphetamines, opiates, and cocaine) in human hair, with subsequent GC–MS confirmation. After decontamination and segmentation into small pieces, 50 mg of hair sample were incubated in 1 ml of methanol during 16 h at 40 °C. A 100 μL aliquot was collected and evaporated to dryness in presence of 100 μL of methanol/hydrochloric acid (99:1, v/v) to avoid amphetamines loss. The dried extract was dissolved in 100 μL of the “sample and standard diluent” solution included in the kit. This solution was submitted to analysis according to the recommended instructions of the manufacturer. During the validation phase, GC–MS confirmations were conducted according to our fully validated and published methods for opiates, cocaine, cannabis, and amphetamines determinations in hair. In a last development step, these procedures were slightly modified to directly confirm ELISA results by GC–MS using the methanolic extract. Ninety-three specimens were simultaneously screened by the ELISA tests (103 for tetrahydrocannabinol (THC)) and confirmed by GC–MS. Twenty were found positive for cannabis (THC: 0.10–6.50 ng/mg), 21 for cocaine (0.50–55.20 ng/mg), 24 for opiates (6-acetylmorphine (6-AM): 0.20–11.60 ng/mg, MOR: 0.20–8.90 ng/mg, codeine (COD): 0.20–5.90 ng/mg), and 13 for amphetamines (AP: 0.20 and 0.27 ng/mg, methamphetamine (MAP): 0.30 and 1.10 ng/mg, methylenedioxymethamphetamine (MDMA): 0.22–17.80 ng/mg). No false negative results were observed according to the Society of Hair Testing's (SoHT) cutoffs (0.5 ng/mg for cocaine, 0.2 ng/mg for opiates and amphetamines, and 0.1 ng/mg for THC). The One-Step™ ELISA kits appear suitable due to their sensitivity and specificity for drug of abuse screening in hair. This technology should find interest in workplace drug testing or driving license regranting, especially when many samples have to be tested with a high rate of negative samples, as ELISA is an easy and high-throughput method.  相似文献   
30.
目的 建立测定单根毛发中吗啡含量的放免方法。方法 用卵清蛋白-琥珀酰吗啡作免疫原,免疫新西兰白兔获得高品质抗血清;HPLC纯化~(125)Ⅰ-吗啡,建立放射免疫方法,测定正常人和吸毒人员单根毛发。结果 抗体亲和常数为3.25×10~(11)L/M,放化纯度为95%,比放射性112μCi/μg;方法的灵敏度为0.01ng/ml。对5例正常人及5例戒毒所吸毒人员的单根毛发进行了检测。单根毛发长度9~24cm,重量为0.7~2.1mg,5例正常人测值为1.75±0.37ng/mg(x±s);5例吸毒人员测值为471±204ng/mg(x±s)。结论 所建方法可准确定量单根毛发中吗啡的含量。  相似文献   
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