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541.
为了探讨补体 C5在心肌梗死死后诊断的特异性,应用免疫组织化学和图像分析技术 ,对正常心脏、心肌梗死及其它非梗死性的引起直接或间接心脏损害的情况如心肌炎、窒息、电击死、出血性休克、心挫伤、有机磷中毒等心肌细胞内 C5的变化进行研究。结果发现: C5仅在心肌梗死与心肌炎病例出现阳性反应,其阳性反应面积同正常对照组存在显著性差异,在窒息、电击死、出血性休克、心挫伤、有机磷中毒等病例未见明显阳性反应。因此 C5作为心肌梗死死后诊断指标仅受心肌炎的影响,对诊断心肌梗死具有较好的特异性。 相似文献
542.
543.
作者通过大鼠乌头碱中毒心肌线粒体 CCO 的超微结构定位,观察到乌头碱引起 CCO 的定位紊乱。由于损害程度不同,出现三种情况:(1)CCO 失去在线粒体嵴膜和内膜上的定位,酶反应产物呈自由扩散状态,酶反应强度对照组有所增强或相似;(2)CCO 失去在线粒体嵴膜和内膜上的定位,酶反应强度较对照组明显减弱;(3)在同一线粒体中部分保持 CCO 的嵴膜、内膜定位,部分失去 CCO 在嵴膜和内膜上的定位。实验结果表明,乌头碱干扰了心肌细胞呼吸链的电子传递,抑制氧化磷酸化的正常进行,导致心肌能量代谢障碍。 相似文献
544.
Maíra Kerpel dos Santos PhD Alexander Acosta PhD Ryan Capote BS Bakhtawar Tabassam BS James Ley PhD Martin Quirke PhD José Almirall PhD 《Journal of forensic sciences》2023,68(4):1162-1177
The 4- Aminophenol (4-AP) colorimetric test is a fast, easy-to-use, and cost-effective presumptive assay of cannabis plant material producing different chromophores with THC-rich cannabis (blue color) and with CBD-rich cannabis (pink color). The main drawback of the 4-AP test is a brief observation window where the color rapidly changes to black, limiting the utility of the test. We now report for the first time, the identification of the product chromophores between 4-AP and CBD/THC as well as propose an explanation and a solution for the color degradation of the chromophores. The identification of the chromophores is provided by spectroscopic (UV–Vis), chromatography, and mass spectrometry (TLC and LC-QToF-MS). Oxidation of excess 4-AP (Reagent A) in the presence of NaOH (Reagent B) produces the black color observed for the previously reported 4-AP tests and reported in the literature. The adjustment of reactants concentrations and volumes of 4-AP:THC/CBD to a 1:1 ratio significantly reduces the black oxidation by-product and increases the observation window up to 2 h instead of the previously reported 5–10 min. For the first time, mass spectrometry and chromatography confirmed that the reaction of THC and CBD with 4-AP produced chromophores with m/z (M + H) = 420, consistent with proposed indophenol structures. The TLC method developed confirmed the separation between CBD and THC chromophores. The specificity of the test is also reported, showing false positive results for the presence of THC (blue color) for samples of thyme and oregano. LDA and SIMCA models showed that the optimized 4-AP procedure performs better than the previously reported 4-AP color test. 相似文献
545.
目的通过测定免疫正常人、β-内酰胺类药物过敏者以及非离子型造影剂过敏者血液中CD63、肥大细胞羧肽酶A3(MC-CPA3)、人末端补体复合物SC5b-9,探讨嗜碱性粒细胞活化试验(basophil activation test,BAT)在非离子型造影剂过敏反应中的诊断价值。方法采用流式细胞术测定全血中嗜碱性粒细胞CD63表达率。采用ELISA法测定血清中MC-CPA3、血浆中SC5b-9含量。结果非离子型造影剂和β-内酰胺类药物过敏者血液中嗜碱性粒细胞CD63表达率、MC-CPA3以及SC5b-9含量均较免疫正常人升高(P0.05)。结论非离子型造影剂过敏者血液中嗜碱性粒细胞和肥大细胞发生活化,补体系统的激活也参与了非离子型造影剂过敏反应的发生。流式细胞术分析BAT可作为非离子型造影剂过敏反应的诊断方法。 相似文献
546.
目的采用CT容积再现技术(CT volume rendering technique,CT-VRT)测量西南地区汉族人胸骨柄体和,建立其与身高的回归方程。方法 160例(男、女性各80例)西南地区汉族成年体检者通过CTVRT(重建层厚1 mm)分别测量胸骨柄长和体长,二者的代数和即为柄体和。同时测量受检者真实身高,分别建立男、女性柄体和与身高的回归方程。结果分别建立了男、女性胸骨柄体和(x3)与身高(y)之间关系的一元回归方程(男性:y=135.000+2.118 x3;女性:y=120.790+2.808 x3)。两方程均具有统计学意义(P0.05),且预测准确性均为100%。结论 CT-VRT能作为胸骨指标测量的有效方法。采用CT-VRT测量的胸骨柄体和能应用于西南地区汉族人身高推算。 相似文献
547.
Andrew Glencross 《Democratization》2013,20(1):123-141
This article explores how proposals for democratizing the European Union (EU) according to a supranational, contestational model are likely to disrupt its existing political system. The current EU is characterized by a dual system of representation that combines the representation of member states with that of individual citizens. Democratization typically entails enhancing the representation of individuals at the expense of state prerogatives. It is thus possible to make a pertinent analogy with the antebellum United States, which also featured dual representation, and where a great wave of democratization took place following Andrew Jackson's presidency (1829–1837). As the system of representation there became more majoritarian, John C. Calhoun led the calls for introducing new anti-majoritarian constitutional safeguards. A transatlantic comparison suggests the contestational system born of EU democratization will require institutional innovation in order to prove viable. In this context, Calhoun's theory of nullification, an ex post political mechanism wielded by the units to stymie federal legislation, appears more appropriate as an anti-majoritarian bulwark and better able to engender constitutional debate over competences than is the EU's stillborn judicial principle of subsidiarity. In similarly Calhounian fashion, a bottom-up procedure of constitutional amendment originating in the units is further proposed as a way of establishing unit acquiescence to greater supranationalism. 相似文献
548.
For more than 30 years, significant research in the United States has found that racial and ethnic minorities suffer disproportionately from nearness to environmental disamenities compared with white non-Hispanics and that these results persist even controlling for poverty and “which came first,” the minorities or the disamenities. The engrained discriminatory findings of this environmental justice (EJ) research have led some to argue that we observe “systemic racism,” built into our social systems in ways that may be difficult to perceive. Yet, within the history of the United States, racial and ethnic minorities are not the only groups that have been systematically discriminated against; various religious groups also have histories of discrimination. Here we consider whether, holding constant race and ethnicity, some religious groups may also suffer from “EJ syndrome.” Since the US Census does not collect data on religion, to measure the presence of some religious groups that may be discriminated against, we use an original dataset on the presence of Jewish, Muslim, Church of Jesus Christ of Latter-day Saints (LDS, aka Mormon), and Roman Catholic houses of worship within California's Census tracts. Our results indicate that even controlling for race/ethnicity and income, the presence of Jewish or Muslim houses of worship in a California Census tract increases the likelihood of environmental burden as measured by the CalEnviroScreen 3.0 index of pollution and community vulnerability. 相似文献
549.
The advocacy coalition framework (ACF), a unified framework for understanding the policy process, has been applied in various countries and regions; however, there are few contributions from Japan, despite seemingly favorable conditions for applying it. An exploration of what hinders ACF applications in Japan is worthwhile for developing the ACF as a framework for comparative policy process studies across various social and political settings. Therefore, this study aims to systematically review previous Japanese ACF studies. Our review found that Japanese ACF studies are fewer in number, have less coverage of policy fields, and have less methodological diversity and transparency than international trends. While most of the Japanese ACF studies supported the basic hypotheses of the ACF, we found a need to refine some hypotheses and research methods of the ACF studies. We also discuss the background factors in the inactivity of ACF studies in Japan and suggest solutions for it. 相似文献
550.
Suely K. S. S. Porto M.S. Thiago Nogueira Ph.D. Lucas Blanes Ph.D. Philip Doble Ph.D. Bruno D. Sabino Ph.D. Claudimir L. do Lago Ph.D. Lúcio Angnes Ph.D. 《Journal of forensic sciences》2014,59(6):1622-1626
A method for the identification of 3,4‐methylenedioxymethamphetamine (MDMA) and meta‐chlorophenylpiperazine (mCPP) was developed employing capillary electrophoresis (CE) with capacitively coupled contactless conductivity detection (C4D). Sample extraction, separation, and detection of “Ecstasy” tablets were performed in <10 min without sample derivatization. The separation electrolyte was 20 mm TAPS/Lithium, pH 8.7. Average minimal detectable amounts for MDMA and mCPP were 0.04 mg/tablet, several orders of magnitude lower than the minimum amount encountered in a tablet. Seven different Ecstasy tablets seized in Rio de Janeiro, Brazil, were analyzed by CE‐C4D and compared against routine gas chromatography‐mass spectrometry (GC‐MS). The CE method demonstrated sufficient selectivity to discriminate the two target drugs, MDMA and mCPP, from the other drugs present in seizures, namely amphepramone, fenproporex, caffeine, lidocaine, and cocaine. Separation was performed in <90 sec. The advantages of using C4D instead of traditional CE‐UV methods for in‐field analysis are also discussed. 相似文献