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991.
3,4-methylenedioxyamphetamine (MDA) derivatives are increasingly abused central nervous system stimulants with neurotoxic properties. In recent years a number of controlled substance analogs (designer drugs) with high structural variety reached the illegal market making their identification an arduous task. The underivatized compounds give very similar or even virtually identical electron impact mass spectra containing mainly intense C(n)H(2n+2)N(+) immonium ions. Using tandem mass spectrometry (MS-MS) the additional structural information contained in the collision induced dissoziation (CID) mass spectra of molecular ions using electron impact (EI) and especially chemical ionization (CI) allowed an unequivocal differentiation of 18 studied regioisomeric 1-(methylenedioxyphenyl)-2-propanamines and 1-(methylenedioxyphenyl)-2-butanamines.Further synthetic methods are presented for 1-(3,4-methylenedioxyphenyl)-N-propyl-2-butanamine, N-isopropyl-1-(3,4-methylenedioxyphenyl)-2-butanamine and four 1-(2, 3-methylenedioxyphenyl)-2-butanamines. N-alkylated 1-(3, 4-methylenedioxyphenyl)-2-butanamine compounds (e.g. MBDB) are also known to be abused psychoactive agents (entactogenes) without the sympatomimetic effects of the 3,4-methylenedioxyamphetamines.  相似文献   
992.
This paper describes a collaborative exercise organised under the auspices of the European Network of Forensic Science Institutes (ENFSI). The purpose of this EU (European Union) funded group is to carry out research to enable STR loci to be compared between European laboratories, ultimately leading to the formation of a pan-European database. Accordingly, an exercise was designed to evaluate a prototype STR multiplex system manufactured by Applied Biosystems (ABD). Each laboratory was sent 12 samples to analyse along with a multiplex kit. Of specific interest was the definition of parameters to define the efficiency of the system. Stutter, split allelic peaks (differing by one base), pull-up, heterozygous balance and between locus balance were all objectively measured. Once the important parameters are defined it is possible to directly compare performances of different multiplexes and the different laboratories carrying out the tests. Since the multiplex used was a prototype system, this exercise cannot be regarded as a proficiency test.  相似文献   
993.
Due to differences in hair growth rate depending on anatomical region, age, gender, ethnicity and interindividual variability, interpretation of parent drug or/and metabolite concentrations in hair is not easy. Furthermore, as drug incorporation mechanisms into hair matrix is not yet fully understood, it is rather difficult to extrapolate details on time and dose from hair segment analysis. If incorporation sources other than from bloodstream (skin secretions and/or external/environmental contamination) are considered, interpretation becomes even more complicated. For evaluating possible passive contamination, it is essential to consider specific identification of metabolites, use of metabolite-to-parent drug ratios, assays of decontamination washes and analysis of specimens collected from other body parts. Cosmetic hair treatment, natural and artificial hair colour, differences in hair structure and specificity of analytical methodology may represent other bias sources affecting concentrations of drugs in hair. A suitable cut-off level related to the LOD will allow correct identification of drugs or metabolites in hair. Regarding the performance of different hair testing laboratories, little information is available at this time to what extent test results are comparable and their interpretation is consistent. Frequency of drug consumption and time intervals between multiple consumption or lag time between consumption and appearance in the hair has not been fully investigated and needs further research.  相似文献   
994.
995.
On 28 September 2000, the Constitutional Court of South Africa ruled that South African Airways (SAA) violated the constitutional rights of Jacques Hoffmann in September 1996 by refusing to employ him as a cabin attendant on the ground that he is HIV-positive.  相似文献   
996.
In the last issue, we reported on a ruling of a Panel of the World Trade Organization (WTO) that Canada was in breach of the international Agreement on Trade-Related Aspects of Intellectual Property Rights (the TRIPS Agreement). The Panel found that Canada's Patent Act does not provide the minimum patent terms required by the trade agreement. Canada appealed that decision, but on 18 September 2000 the WTO Appellate Body upheld the Panel ruling.  相似文献   
997.
The authors review the Business Judgment Rule as applied to a not-for-profit director's duty of care, with particular emphasis on the different forms of state statutory liability shields that serve to enhance the protections of the Rule. They also examine current trends in enforcement of breach of fiduciary duty of care standards, and provide a series of specific recommendations for not-for-profit boards to consider implementing as a means of increasing the likelihood of affording such protections to individuals serving as directors.  相似文献   
998.
999.
During the 1960s, there emerged a youth culture which had two major orientations: the Counterculture and the Movement. We are well informed about this youth culture, its social values, social norms, and emergent social roles (e.g., hippie, freak, radical, dropout). Part of these social and political movements was the creation of alternative, counterculture, or radical human service programs. Early examples were free medical clinics, drop-in centers, and telephone hotlines. Among the actual differences in these programs compared to older, established human service agencies was (is) the prominent position of the social value of client anonymity. This notion of client anonymity is examined in the attempt to understand its role in the relations among themes of the Counterculture, individual youth, their peers, and youth-serving agencies.Holds degrees in social work and public health and is currently completing a report of a national survey of hotlines and youth crisis programs and working with others in editing papers for a monograph from a conference on evaluating hotlines. The survey data will appear in that publication.  相似文献   
1000.
SAWYER  C. R. 《African affairs》1955,54(217):312-316
"To add a library to a house, is to give that house a soul."  相似文献   
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