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251.
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   
252.
Emotional, physiological and physical stress is associated with increased rates of cerebrovascular events and sudden deaths. The pathophysiology of stress-induced cardiomyopathy is not well understood. Proposed mechanisms for catecholamine-mediated stunning in stress cardiomyopathy include epicardial vasospasm, microvascular dysfunction, hyperdynamic contractility with midventricular or outflow tract obstruction, and direct effects of catecholamines on cardiomyocytes. Studies show evidence of significant heritable influences on individual responses to adrenergic stimulation. Data from such studies may be of help for a more accurate comprehension of clinical and morphological alterations of the heart. Irrespective of the cause, patients with the classic stress-induced cardiomyopathy morphology deserve special attention because this extensive distribution of wall motion abnormalities has implications for potential associated complications. Cardiac response may be significantly coupled to genetic differences at candidate loci that encode components of catecholamine biosynthesis, storage, and metabolic pathway. Given the role of the sympathetic nervous system in responses to acute stress, it is reasonable to explore whether genetically determined alterations in catecholamine system functions contribute to acute and chronic cardiovascular disorders such as stress-induced cardiomyopathy.  相似文献   
253.
This study consisted of three parts to evaluate the performance of Lumicyano? on a variety of fabrics. One part assessed the impact of dye percentage (8%, 9% and 10%) on visualisation of fingermark detail and luminescent brightness in split grab marks. A 9% dye produced the highest quality detail of grab impressions with least interference from background fluorescence. The second part investigated the optimal relative humidity (RH, 75–84%) for certain fabric types using Lumicyano on split, six-series depletion fingermarks. It was concluded that the recommended RH of 80% remained the ideal cyanoacrylate fuming environment. The final and third part of this study determined the impact of sequential addition of Basic Yellow 40 (BY40) on Lumicyano compared to traditional cyanoacrylate (CA) followed with BY40 application. Results from this study demonstrated that Lumicyano on its own developed fingermarks with superior quality to Lumicyano with sequential addition of BY40 or traditional cyanoacrylate followed by BY40. Inclusion of more fabrics, donors and longer ageing periods should be explored in future studies to determine what frameworks are best for certain types of fabrics.  相似文献   
254.
In 2002 the Australian Parliament enacted legislation which prohibited both therapeutic and reproductive embryonic cloning. Just four years later, in December 2006, this same legislation was amended, reversing the prohibition on therapeutic cloning, while retaining the ban on reproductive cloning. The Prime Minister, sensing the political mood, allowed a conscience vote. This contrasted with his decision several months earlier against introducing any changes to the 2002 Act, despite 54 recommendations having been made by a Statutory Review Committee. Approval of the legislation had as much to do with the careful drafting of the provisions as with any rational, social or scientific factor. The legislation is narrow in scope, retains an absolute prohibition on reproductive cloning and contains strict regulations with heavy criminal penalties. The Act requires a review after three years. A number of questions remain. Does stem cell research demand a global rather than a local approach, by way of an international Covenant? Does the legal status of a cloned embryo need further examination? Will the embryo have a separate legal standing recognised by law? These are some of the questions which will need addressing as the law tries to keep up with science.  相似文献   
255.
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   
256.
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   
257.
258.
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   
259.
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   
260.
The effects of age of witness, gender of witness, lineup presentation, and practice on eyewitness testimony were investigated. Ninety-six elementary-school children and 96 college students viewed a slide sequence of a crime, followed by target-present or target-absent photo identification in sequentially or simultaneously presented lineups. Prior to photo identification, half the subjects received a practice lineup. Children had a higher rate of choosing than adults, resulting in more foil identification errors in both target-present and target-absent lineups. Without prior practice, sequential presentation as compared to simultaneous presentation reduced errors in target-absent lineups for adult witnesses and showed a similar but nonsignificant reduction for child witnesses. With prior practice, sequential presentation lost the advantage over simultaneous presentation in target-absent error reduction. Practice reduced target-absent errors in simultaneous-presentation lineups for both age groups.  相似文献   
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