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321.
目前,欧洲民众对美国的评价跌到了历史最低点。从短期看,这次美国在欧洲的民意危机主要是来自两方面:布什总统和美国出兵伊拉克。2004年夏,仅有不到五分之一的欧洲人对美国总统有好感,而四分之三多的欧洲人认为伊拉克战争是个错误。美国士兵虐俘的骇人图片进一步恶化了美在欧洲人心目中的形象。但是此外还存在着更深刻和长期的政治、经济、社会发展等方面的因素。这些因素影响着跨大西洋的关系和欧美相互的看法。2004年6月,布什三访欧洲:参加诺曼底登陆日的六十周年纪念活动、出席爱尔兰欧美峰会和伊斯坦布尔北约峰会。当他被问及欧洲及其他地区对其支持率不高  相似文献   
322.
When submitting samples for analysis, maintaining sample integrity is essential. Appropriate packaging must be used to prevent damage, contamination or loss of sample. This is particularly important for stable isotope analysis by isotope ratio mass spectrometry as this technique is capable of detecting subtle differences in isotopic composition with great precision. In a novel study, scalp hair and fingernail samples were placed in five different types of packaging, routinely used in forensic laboratories and stored for 6 weeks and 6 months. Samples were subsequently cleaned and submitted for (13)C/(12)C, (15)N/(14)N, (2)H/(1)H and (18)O/(16)O analysis. Results from (13)C analysis indicate that type of packaging can cause slight changes in (13)C abundance over time. Differences were noted in the (15)N isotope signatures of both hair and nail samples after 6-week storage, but not after 6 months. This apparent discrepancy could be a result of the packaging not being properly sealed in the 6 weeks study. Fewer differences were noted when analyzing samples for (2)H and (18)O abundance.  相似文献   
323.
Abstract:  Following implementation of our automated process incorporating the Promega DNA IQTM system as a DNA extraction method, a large number of blood-containing exhibits failed to produce DNA. These exhibits had been tested with the Hemastix® reagent strip, commonly used by police investigators and forensic laboratories as a screening test for blood. Some exhibits were even tainted green following transfer of the presumptive test reagents onto the samples. A series of experiments were carried out to examine the effect of the Hemastix® chemistries on the DNA IQTM system. Our results indicate that one or more chemicals imbedded in the Hemastix® reagent strip severely reduce the ability to recover DNA from any suspected stain using the DNA IQTM magnetic bead technology. The 3,3',5,5'-tetramethylbenzidine (TMB) used as the reporting dye appears to interact with the magnetic beads to prevent DNA recovery. Hydrogen peroxide does not seem to be involved. The Hemastix® chemistries do not interfere in any way with DNA extraction performed using phenol-chloroform. The incompatibility of the Hemastix® chemistries on the DNA IQTM system forced us to adopt an indirect approach using filter paper to carry out the presumptive test.  相似文献   
324.
The objective of this study was to compare urinary excretion patterns of two cannabinoid metabolites in subjects with a history of chronic marijuana use. The first metabolite analyzed was nor-9-carboxy-delta9-tetrahydrocannabinol (delta9-THC-COOH), the major urinary cannabinoid metabolite that is pharmacologically inactive. The second metabolite 11-OH-delta9-THC is an active cannabinoid metabolite and is not routinely measured. Urine specimens were collected from four subjects on 12-20 occasions > or = 96 h apart in an uncontrolled clinical setting. Creatinine was analyzed in each urine specimen by the colorimetric modified Jaffé reaction on a SYVA 30R biochemical analyzer. All urine specimens analyzed for 11-OH-delta9-THC had screened positive for cannabinoids with the EMIT II Plus cannabinoids assay (cut-off 50 ng/mL) on a SYVA 30R analyzer and submitted for delta9-THC-COOH confirmation by GC-MS (cut-off concentration 15 ng/mL). Eleven-OH-delta9-THC was measured by GC-MS with a cut-off concentration of 3 ng/mL. Both GC-MS methods for cannabinoid metabolites used deuterated internal standards for quantitative analysis. The mean (range) of urinary delta9-THC-COOH concentration was 1153 ng/mL (78.7-2634) with a cut-off of 15 ng/mL. The mean (range) of delta9-THC-COOH/creatinine ratios (ng/mL delta9-THC-COOH/mmol/L creatinine) was 84.1 (8.1-122.1). The mean (range) urinary of 11-OH-delta9-THC concentration was 387.6 ng/mL (11.9-783) with a cut-off of 3 ng/mL, and the mean (range) of 11-OH-delta9-THC/creatinine ratio (ng/mL 11-OH-delta9-THC/mmol/L creatinine) was 29.7 (1.2-40.7). Of the 63 urine specimens submitted for delta9-THC-COOH confirmation by GC-MS, 59/63 urine specimens (94%) were positive for delta9 -THC-COOH and 51/63 (81%) were positive for 11-OH-delta9-THC. Overall, the concentrations of 11-OH-delta9-THC in urine specimens collected > or = 96 h apart were lower than delta9-THC-COOH concentrations in 50/51 of the urine specimens in this population. Further urinary cannabinoid excretion studies are needed to assess whether 11-OH-delta9-THC analyses have a role when assessing previous marijuana or hashish use in chronic users whose urine specimens remain positive for delta9-THC-COOH for an extended period of time after last drug use.  相似文献   
325.
In forensic medicine, there is a need for more sensitive biochemical markers for the post-mortem diagnosis of acute myocardial infarction. A study of the distribution of biochemical markers in different fluids is of great significance in post-mortem diagnosis, because their distribution depends on the location of tissue damage and release kinetics. The aim of this study is to compare the sensitivities and specificities of creatine kinase-MB (CK-MB), myoglobin and cTnI in serum and pericardial fluid for the post-mortem diagnosis of acute myocardial infarction (AMI). We studied 188 cadavers selected during 1 year from medicolegal autopsies. The groups were as follows: (1) myocardial infarction (n = 52); (2) asphyxia (n = 59); (3) multiple trauma (n = 41); (4) natural deaths excluding myocardial infarction (n = 36). We obtained statistically significant differences in pericardial fluid for all the biochemical markers, the highest levels being obtained in the group of cadavers who had died from myocardial infarction. A common factor is the high negative predictive value found in biochemical markers, which is contrary to the findings obtained in clinical practice, when the percentages of sensitivity are very high.  相似文献   
326.
Subjects with a history of chronic marijuana use were screened for cannabinoids in urine specimens with the EMIT((R)) II Plus cannabinoids assay with a cut-off value of 50 ng/ml. All presumptively positive specimens were submitted for confirmatory analysis for the major urinary cannabinoid metabolite (Delta(9)-THC-COOH) by GC-MS with a cut-off value of 15 ng/ml. Creatinine was analyzed in each specimen as an index of dilution. Huestis and Cone [J. Anal. Toxicol. 22 (1998) 445] reported that serial monitoring of Delta(9)-THC-COOH to creatinine ratios in paired urine specimens collected at least 24h apart could differentiate new drug use from residual Delta(9)-THC-COOH excretion. The best accuracy (85.4%) for predicting new marijuana use was a Delta(9)-THC-COOH/creatinine ratio > or =0.5 (dividing the Delta(9)-THC-COOH to creatinine ratio of specimen 2 by the specimen 1 ratio). In a previous study in this laboratory [J. Anal. Toxicol. 23 (1999) 531], urine specimens were collected from chronic marijuana users at least 24h apart and dilute urine specimens (creatinine values <2.2 micromol/l) were excluded from the data analysis. The objective of the present study was to determine whether creatinine corrected urine specimens positive for cannabinoids could differentiate new marijuana use from the excretion of residual Delta(9)-THC-COOH in chronic users of marijuana based on the Huestis 0.5 ratio. Urine specimens (N=946) were collected from 37 individuals with at least 48h between collections. All urine specimens were included in the data review irrespective of creatinine concentration. The mean urinary Delta(9)-THC-COOH concentration was 302.4 ng/ml, mean Delta(9)-THC-COOH/creatinine ratio (ng/ml Delta(9)-THC-COOH/(mmol/l) creatinine) was 29.3 and the Huestis ratio calculation indicated new drug use in 83% of all sequentially paired urine specimens. The data were sub-divided into three groups (A-C) based on the mean Delta(9)-THC-COOH/creatinine values. Interindividual Delta(9)-THC-COOH/creatinine mean values ranged from 2.2 to 13.8 in group A (264 specimens, N=15 subjects) where 80.7% of paired specimens indicated new drug use. In group B, mean Delta(9)-THC-COOH/creatinine values ranged from 15.3 to 37.8 in 444 specimens (N=14 subjects) and 83.3% of paired specimens indicated new drug use. In group C, individual mean Delta(9)-THC-COOH/creatinine values were >40.1 (41.3-132.5) in 238 urine specimens (N=8 subjects) and 85.3% of paired urine specimens indicated new marijuana use. Correcting Delta(9)-THC-COOH excretion for urinary dilution and comparing Delta(9)-THC-COOH/creatinine concentration ratios of sequentially paired specimens (collected at least 48h apart) provided an objective indicator of new marijuana use in this population.  相似文献   
327.
1,4-Dihydropyridines calcium channel antagonists (1,4-DHP CCAs) are photolabile and the products of their photodecomposition have no pharmaceutical activity. In our previous work we have presented a screening procedure for eleven 1,4-DHPs in plasma by LC-MS-MS using multiple reaction motoring. The laboratory process includes preparation and storage of stock solutions, plasma storage, solid-phase extraction, reconstitution of extracts and storage time in an autosampler for LC-MS-MS analysis. Prior to validation of the analytical procedure, we have tested the stability of these compounds by exposure to light. Methanolic solutions have been exposed to laboratory and UV light and the stability of the compounds in plasma was tested by exposure of spiked plasma samples to laboratory light at room temperature. Stability during freeze-thaw cycles and stability during 2 month storage at -20 degrees C have been tested as well. Products of photodecomposition have been identified after forced degradation and the degree of degradation has been quantified using LC-UV-DAD and LC-MS-MS, respectively. A 96% degradation after only 2h has been observed when solutions of nifedipine or nisoldipine were exposed to laboratory light in clear glass vials. In plasma samples degradation was 25% in only 2h for both compounds. The main degradation product was produced by oxidation of the dihydropyridinic ring resulting in the pyridine analogue that has been described as the first metabolite in the metabolic pathway. Only minor degradation was found for the other tested compounds after 2h light exposure in methanolic solutions. Furthermore, lercanidipine and nicardipine were also degradated by esterhydrolysis. Several additional minor degradation products were found for the other tested 1,4-DHPs, however, some of them could not be identified. Preconditions for storage and handling of plasma samples prior to and during analysis for 1,4-DHP CCAs are suggested in order to avoid photodecomposition of the analytes.  相似文献   
328.
Much of the criminal justice literature indicates that people’s support for harsh criminal sanctions such as the death penalty is strongly related to their beliefs about deterrence and their beliefs about retribution. In this paper, using social dominance theory as our organizing framework, we expand upon this literature by showing that social dominance orientation (SDO) is also related to support for harsh criminal sanctions, as well as to deterrence and retribution beliefs. In addition, we show that the relationships between SDO, on the one hand, and support for various forms of severe criminal sanctions, on the other, are mediated by deterrence and retribution beliefs.
Jim SidaniusEmail:
  相似文献   
329.
Most Australian jurisdictions have mandatory reporting legislation to compel members of selected professional groups, including nurses, to report suspicions that a child has been or is likely to be subjected to abuse or neglect. This article details the legal obligations of nurses in each jurisdiction, and highlights differences between jurisdictions. Problematic features of the laws are identified, including the use of ambiguous concepts like "reasonable" suspicion and "significant" harm. Literature is reviewed to identify what is known about nurses' legal knowledge, actual reporting practice, and the practical problems that arise for nurses in this context. It is concluded that empirical research needs to be conducted, because it is not known if the laws are practically effective, whether nurses have sufficient training in, and knowledge of, their reporting duties, or what factors influence sound reporting. Such research can inform both the development of sound training systems and recommendations for legal reform.  相似文献   
330.
In the following discussion we approach the issue of police legitimacy inNorthern Ireland through Habermas's theory of legitimacy and the shiftinglocus of conflict from the economic to the cultural sphere. It is argued thatthe cultural sphere is often a major site of conflict in divided societies suchas Northern Ireland. The process of economic globalisation – a crucialfactor in the emergence of identity based movements elsewhere – has hadthe effect of intensifying conflict over identity and its symbolicrepresentation. The debate on the reform of the RUC in the wake of thePatten Commission Report has focused principally on the recommendationthat the symbolism of the police be changed. Although this conflict oversymbols condenses the central problem of the exclusion and misrecognitionof nationalists it also has the effect of distracting attention from the moreuniversal theme of the Report: the relationship between citizens, police andthe state.  相似文献   
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