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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.
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994.
体外培养FBs损伤模型的建立及细胞免疫组化研究   总被引:2,自引:2,他引:0  
首次应用培养人胎肺成纤维细胞 (FBs)损伤模型 ,体外研究创缘FBs合成细胞型纤维连接蛋白 (cellu larfibronectins,cFn)的变化与损伤时间的关系。结果表明 ,损伤使处于静息状态的融合FBs成为具有运动能力和增殖能力的活跃细胞。应用免疫组化ABC法结合图像分析技术 ,观察伤后不同时间创缘FBs内cFn的含量变化。伤后 1h ,可以检测到cFn有变化 ,且在伤后 6h内 ,cFn逐渐增多 ,其变化与损伤时间呈正相关。这对今后应用cFn与损伤时间推断的研究提供了科学依据 ,同时为法医学损伤时间研究开辟了新的途径。  相似文献   
995.
大鼠肝细胞DNA含量与早期死亡时间关系的图像分析研究   总被引:16,自引:7,他引:9  
Lin LQ  Liu L  Deng WN  Zhang L  Liu YL  Liu Y 《法医学杂志》2000,16(2):68-69
实验选择 15只大鼠 ,处死后 ,在 2 4h内 ,每隔 1h取肝组织块进行细胞学涂片、福尔马林液固定、Feul gen染色、自动图像分析仪测量、统计学处理数据。结果表明 ,肝细胞DNA含量在死后 2 4h内 ,随死亡时间的延长而较有规律的下降。其中积分光密度、平均光密度、异形指数是用来研究死亡 2 4h内肝细胞DNA降解规律 ,并准确推断死亡时间的较好指标。  相似文献   
996.
损伤对培养人胎肺FBs分泌Fn的影响及与损伤时间的关系   总被引:1,自引:1,他引:0  
Shen Y  Zhao Z  Chen Y  Yan Z  Gu Y  Wu W  Liao Y 《法医学杂志》2000,16(3):129-131
为了探讨损伤对FBs分泌Fn的影响及与损伤时间的关系 ,在本室建立的体外培养人FBs损伤模型的基础上 ,应用酶联免疫组织化学检测技术 (双抗体夹心法ELISA)对损伤后不同时间培养液中Fn的含量变化进行检测 ,结果表明 :伤后培养人胎肺FBs合成分泌的cFn的量 ,在伤后6h内与损伤时间呈正相关。  相似文献   
997.
The HIV/AIDS epidemic continues to be a leading public health issue in the United States. During the past decade, the epidemic has shifted away from the gay community, although gay and bisexual men continue to be the largest single HIV exposure category. Now, HIV increasingly affects low-income people of colour in urban areas, as well as women. As AIDS becomes more and more a minority, inner-city disease, public focus on the epidemic as a significant social and political issue is waning. While a full survey of current issues in US law is beyond the scope of this article, the focus here is on current issues that are highly relevant to the direction the epidemic appears to be taking.  相似文献   
998.
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   
999.
Conclusion The problem of revisionism, or efforts to deny and censor the incontrovertible history of known genocides, is a growing one. It is now clear that denial is inevitably a phase of the genocidal process, extending far beyond the immediate politically expedient denials of governments who are currently engaging in genocidal massacre or have just recently done so—i.e., the Chinese government's abject denials of the killings of some 5,000 in Tiananmen Square, or the Sri Lanka government's denials of the state-organized massacre of 5,000 Tamil. Denials of genocide continue long after the event by a variety of groups and people, including successor governments or successor enemies of the victim people, such as anti-Semites against Jews, Turks against Armenians, and bigots and celebrants of violence and murder of all sorts. But such denials also occur—and this is the most perplexing fact—among a variety of not obviously malevolent people, including intellectuals who, in the process of calling for a better world, effectively exonerate, support, encourage, and participate in denials of a known genocide, implicitly condoning and even celebrating its occurrence, meanings, and portents for the future. This article is an effort to study and analyze this latter phenomenon, which has been little recognized. Together with previous essays on the psychology of more explicit malevolent denials of genocide, the intention is to generate a broader psychological theory of denials of genocide and revisionism by proposing that there are also a variety of “innocent denials” of the factual reality or significance of known cases of genocide, and a variety of “innocent disavowals of violence” which in truth celebrate the violence. These “innocent denials” join with the well-known explicit bigots in creating a vast panorama of dangerous denials of genocides and implicit calls to new genocides in our world. The basic thesis of this article has been under development since its first presentation in a plenary address at the Soviet Academy of sciences in Yerevan, Armenia in 1990 on the occasion of the seventy-fifth anniversary of the Armenian Genocide.  相似文献   
1000.
Modeling Duration Dependence   总被引:1,自引:1,他引:0  
As applications of duration analysis have burgeoned in politicalscience, scholars have become increasingly aware of the potentialsubstantive importance of duration dependence: the extent towhich the conditional hazards of the events of interest arerising or falling over time. Here I discuss the issue of durationdependence, focusing on the distinction between "spurious" dependencedue to unobserved heterogeneity and "true" duration dependencedue to state dependence in the process of interest. I presenta simple extension of a commonly used parametric duration model—theWeibull model—which allows researchers to assess the influenceof causal variables on the nature and extent of duration dependencein their data. I then illustrate the application of this "generalizedWeibull" model using data on the duration of international alliances.  相似文献   
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