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351.
小白鼠死亡后,肝脏不离体恒温保存,定时定量制备肝浸出液为酶样品,催化5’-腺苷酸(5’AMP)生成腺苷和无机磷酸,后者在还原利存在下与钼酸试剂发生蓝色反应,其颜色深度与磷酸含量成正比。用722型分光光度计测定光密度(OD值),计算酶活力。在三种温度下,经5次重复实验,发现小白鼠死亡后在3O℃12小时、18℃21小时、7℃24小时,其酶活力降低均呈明显的规律性。说明此酶用于一定温度和时间范围内的死亡时间推断具有参考价值。  相似文献   
352.
The principles of a special type of senile cerebromeningeal angiopathy, these days usually named “congophilic angiopathy”, are demonstrated on the basis of eight cases, complicated by spontaneous massive intracranial hemorrhages in seven and late traumatic hemorrhage in one of them. The occurrence of massive hemorrhages associated with congophilic angiopathy has until now only rarely been reported. The medicolegal significance of this vascular disease is emphasized by the eighth, traumatic, case, which became forensically relevant; the late massive hemorrhage had to be regarded as significantly favoured by amyloid angionecrosis, which is the main feature of congophilic angiopathy.  相似文献   
353.
Coronary sclerosis is generally supposed to be the most important factor for coronary thrombosis, myocardial infarction and coronary heart death. Stenosing coronary sclerosis may be postmortally documented by angiography and morphometry. It is possible to obtain sufficient morphological data to suggest acute cardiac insufficiency, if the maximum grade of stenoses as a functional parameter and the heart weight are regarded in addition to the quantitative results of the three main branches of the coronary arteries (lumen and intima areas).Generally the cardiac results of autopsy are used individually and subjectively for the explanation of the cause of death. The conclusiveness of these results of autopsy depends on the circumstances of death and the existence of further pathological findings. Competing causes of death may exist in the form of illnesses, injuries, alcoholic and drug effects, physical strain and emotional stress or medical provisions. The quantitative valuation of the cardiac findings with a critical limit for an acute coronary death permits a more exact interpretation of such competing causes of death. This method of examination may also reveal an unpresumed competing cause of death, for example an intoxication. This was demonstrated by four autopsy cases.  相似文献   
354.
为了解广西地区猪繁殖与呼吸综合征病毒(PRRSV)流行毒株的分子遗传进化情况,对2004-2010年间广西的PRRSV阳性病料进行了ORF5、ORF7基因扩增和序列分析。结果显示,所获得的毒株均属于美洲型毒株,其ORF5基因间的氨基酸序列同源性为89.6%~99.5%,与VR-2332、Ch-1a、JXA1株的氨基酸序列同源性分别为84.6%~91%、89.6%~95.5%和93%~99%,而与LV的同源性为54.7%~56.7%;ORF7基因间的氨基酸序列同源性为87.1%~99.2%,与VR-2332、Ch-1a、JXA1株的氨基酸序列同源性分别为91.1%~96%、91.9%~96%和89.5%~99.2%,而与LV的同源性为55.6%~58.1%。基于ORF5和ORF7基因核苷酸序列绘制的遗传进化树,可将所有PRRSV分离株分为4个亚群,广西地区的毒株分布在以CH-1a为代表的Ⅱ亚群、以HB-1为代表的Ⅲ亚群和以JXA1为代表的Ⅳ亚群,以Ⅳ亚群为主。表明当前广西PRRSV流行毒株以美洲型Ⅳ亚群为优势基因亚群,并且各毒株间的ORF5和ORF7基因序列存在一定差异,但没有明显的地域特征。  相似文献   
355.
5-Methoxy-N,N-diisopropyltryptamine (5-MeO-DIPT) is a designer hallucinogen derived from tryptamine and is reportedly abused and involved in criminal activities. For the detection of 5-MeO-DIPT use, a liquid chromatography-tandem mass spectrometric method for 5-MeO-DIPT and its metabolites, 5-hydroxy-N,N-diisopropyltryptamine (5-OH-DIPT) and 5-methoxy-N,N-isopropyltryptamine (5-MeO-IPT) was developed and validated in rat urine. The urine samples were pretreated by protein precipitation with acetonitrile and introduced into a BDS HYPERSIL C(18) column (50 × 2.0 mm, 5 μm) for chromatographic separation. Mobile phases consisted of methanol, water, and 1% formic acid, and gradient elution was used at a flow rate of 0.2 mL/min. For the MS detection, multiple-reaction monitoring analysis was adopted. The linear range was 0.01-10 μg/mL, and the lower limit of quantification was 10 ng/mL for all analytes. The intra- and interday accuracies and precisions met the criteria (<15%). The developed method was successfully applied to the drug-treated rat urine.  相似文献   
356.
目的 探讨针灸干预海洛因复吸的作用机制.方法 采用间断性递增量肌肉注射海洛因的方法复制海洛因复吸大鼠模型,观察针灸对海洛因复吸大鼠条件性位置偏爱(conditional position preference,CPP)的行为学改变及脑组织多巴胺(dopamine,DA)、5-羟色胺(5-hydroxytryptamine,5-HT) 含量变化的影响.结果 针灸能防止海洛因复吸大鼠体质量的下降(P<0.01),显著延长海洛因复吸大鼠在暗箱的停留时间(P<0.01),显著降低海洛因复吸大鼠脑组织DA和5-HT含量(P<0.01).结论 抑制脑组织DA、5-HT的释放,降低对海洛因用药行为有关环境的依赖行为,可能是针灸干预海洛因复吸的作用机制之一.  相似文献   
357.
Abstract: Relationship testing laboratories provide genetic evidence to support or refute claims of kinship between U.S. citizen petitioners and potential immigrant beneficiaries. One female beneficiary presented a male amelogenin type and alleles at 15 autosomal loci that were identical to an alleged brother’s. Laboratory records showed that her alleged father had petitioned to have 15 children emigrate from Ghana. The petitioner’s 15 paternity indices exceeded 105, but the children shared only four short tandem repeat (STR) profiles, suggesting fraudulent reuse of genotypes in this alleged pedigree (AP). To determine the extent of this “genotype recycling,” I examined the laboratory’s 555 APs from Ghana and 532 control APs from Nigeria. Seventeen Ghanaian APs (3.1%) but no Nigerian APs showed genotype recycling. Of 90 tested people in the 17 APs, 56 shared identical STR profiles with others in their AP. Of these 56 people, 10 were petitioners with unexpectedly high parentage indices. Seven of 56 had amelogenin types that disagreed with their declared genders. Database searches for identical multilocus genotypes in allegedly different people would best detect this fraud.  相似文献   
358.
In this paper, we employ the event study methodology to examine shareholder wealth consequences of corporate environmental lawsuits filed in the US Circuit Courts from 1980 to 2001. We find that stocks of defendant firms experience significant negative abnormal returns around the lawsuit filing dates. When the plaintiffs are government entities, the abnormal returns of the defendant stocks are significantly negative. On the other hand, when the plaintiffs are individuals or nonpublic business entities, the abnormal returns are statistically insignificant. When lawsuits are filed under EPA's superfund statute, defendant firms experience significant loss in equity value. For shareholders of the average firm in our sample, the empirical evidence suggests that it does not pay to pollute if the firm is sued.  相似文献   
359.
Corporate liability regimes have two major social goals: (i) inducing corporations to internalize all social ramifications of their activity; and (ii) inducing corporations to prevent, deter, and report their employee misconduct. The scholarly polemic has shown that none of the liability regimes recognized thus far in the literature efficiently satisfies both social goals. Following a Law and Economics approach, this paper develops an innovative regime that may comprise an optimal corporate liability framework in most settings. The Compound Corporate Liability Regime developed in this paper is a two-layer strict liability regime. Under this regime, corporations that self-report their employee misconduct incur a sanction that is reduced by the variable enforcement costs saved due to their self-reporting. Such a liability framework aligns social and corporations’ interests, and thereby satisfies both social goals of corporate liability regimes.  相似文献   
360.
面对能源安全领域的挑战,包括能源结构单一、自给率低、效率进步缓慢和环境问题凸显,东盟五国政府通过能源三大法律政策实施、能源效率奖励机制创新以及区域能源合作网构建等政策保障制度来应对能源安全危机。相似的能源现状为借鉴东盟五国经验奠定了基础。中国应出台和完善保障性能源安全政策,创新能源效率奖励系统,加强能源基础设施建设和深化国际能源合作。  相似文献   
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