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61.
Good gas chromatography (GC) separation of molecules is essential for clean gas chromatography/mass spectrometry (GC/MS) confirmation of compounds. The trifluoro derivatives of ephedrine (E) and methamphetamine (MA) coelute on dimethyl silicone capillary columns, such as DB-1, which are most commonly used by chromatographers. Methods are described to separate E and MA to aid GC/MS confirmations of methamphetamine, ephedrine, or both E and MA together, whichever may be present in Enzyme Immunoassay (EIA)-analyzed amphetamine-positive urine samples. The use of the heptafluoro derivatives of E and MA on a DB-1 column, or the trifluoro derivatives of E and MA on a DB-17 column, is suggested for good gas chromatographic separation.  相似文献   
62.
One case of the erroneous administration of deslanoside and high level of drug in antemortem plasma and postmortem specimens has been reported owing to the unusual surrounding circumstances. Deslanoside in antemortem plasma was determined by FPIA and the analysis was done by HPLC in the postmortem tissue samples. The analytical results and methods used in the examinations are discussed in the following paper.  相似文献   
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Bloodstains were made with 200 microliters blood on each of 11 different common substrates to examine the effect of the stain carrier on the amount and quality of DNA recoverable. High-molecular-weight DNA was extracted from all samples after 2 days. The yield of DNA from each sample varied considerably, not only between the different stain carriers but also within a given category. With a DNA yield of up to 10 micrograms, paper, glass, nylon, wood, smooth leather and wool gave the best results, followed by blue denim and wallpaper (up to 6 micrograms), cotton fabric and carpeting (up to 4 micrograms) and suede (up to 2 micrograms). For several stain carriers the DNA-containing solution was contaminated by chemical substances, which in the case of the blue denim, suede, and carpet samples inhibited the digestion of the DNA with restriction enzymes and prevented DNA typing. The different textures of the stain carriers tested and (as for varying yields on the same carrier) the differing degree of loss of DNA during extraction and the physiological variation in the number of leukocytes in human blood are discussed as possible reasons for the wide range of variation in the amounts of DNA it was possible to extract.  相似文献   
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从在“牢监大学”自学成才到三十年代主编《中国农村》,从在新四军和苏北抗大讲授政治经济学到主持山东解放区的战时财经工作,从建国前夕在西柏坡协助周恩来同志处理即将诞生的新中国的经济工作到为建立社会主义市场经济体制而深入探索,薛暮桥以其睿智的头脑、深邃的思想、精辟的论述,将马克思主义经济理论运用于中国革命和建设的实践,提出了一系列富有创建性的政策主张,为中国的社会主义经济改革与发展作出了重要贡献,从而成为我国经济学界的泰斗、杰出的马克思主义经济学家、新中国社会主义经济理论的奠基人之一。1904年,薛暮…  相似文献   
67.
On the basis of the uncertainty management model, we argue here that when people are uncertain about an organization's trustworthiness, they may resolve the question how they should react toward the organization by relying on their perceptions of the organization's procedures. As a consequence, we predicted that the reactions of parents whose child was in a day care center would be strongly influenced by their perceptions of the procedures used by the organization that was responsible for their children's day care when the parents would be uncertain about the organization's trustworthiness. However, when parents would be certain that the organization could be trusted they would be less in need of procedural information, yielding less strong effects of perceived procedure on parents' reactions. The findings of a survey study corroborate this line of reasoning. In the discussion it is argued that these findings suggest that people especially rely on their perceptions of procedures when they are uncertain about important aspects of their lives, such as the trustworthiness of organizations that are responsible for their children's day care.  相似文献   
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This paper explores the capacity of alternative theoretical perspectives to explain the self-reported criminality of black and white young adult females. When criminal involvement is regressed on the theory operation-alizations separately by race, a key difference emerges: For white women, significant effects are clustered in the social-psychological theory groups (bonding, attitudes, and maturation), but for the black women the social-psychological variables have only scattered and inconsistent eflects. Instead, for black women structural indicators emerge as the important predictors of criminal involvement.  相似文献   
70.
Comparison of a suspected biter's dental arches with the patterned injury of a bite mark is especially difficult when the bite occurs in an anatomic location with a small radius of curvature or with complex or compound curves. The authors present two case reports in which human skin was used as a template for the reproduction of a bite. In one case the victim's skin was used; in the other, the skin of a anatomically similar person was used. The use of inked dental casts, photography, and transparent overlays significantly reduced the errors common to analysis of bite marks in these highly curved areas.  相似文献   
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