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71.
Poisoning can occur with chronic accumulation of a drug due to reduced metabolic capacity; conversely, under‐treatment may occur due to an increased metabolic rate. Over half of all drugs are metabolized by the cytochrome P450 3A complex (CYP3A). The activity of CYP3A can be assessed by the urinary ratio of 6β‐hydroxycortisol to cortisol. The aim of this study was to determine the usefulness of this ratio as a postmortem marker for determining whether altered CYP3A enzyme activity occurred prior to death. In a series of 244 postmortem cases, this ratio ranged from 0.014 to 78.6 (median 3.50). The median was significantly higher (5.14) in a subgroup of 28 cases that exhibited the presence of CYP3A‐inducing drugs. In cirrhosis, the median ratio was 1.69. This pointed to a reduced metabolic capacity of CYP3A. Thus, the ratio may constitute a rough indicator of the CYP3A metabolic capacity, which could be of value in special cases.  相似文献   
72.
3D打印技术如今已受到了社会各界广泛的关注,有着良好的发展前景。然而其本身也具有着一定的治安隐患,如危险物品泛滥、特殊物品复制等。对于3D打印技术,需要进行系统的风险评估,并通过完善机制的构建进行人为控制,以保证其健康发展。这一机制的构建,除了应运用较多的高科技手段外,也应当在管理规范层面做到有序、协调。  相似文献   
73.
ABSTRACT

The negotiations with Iran about its nuclear programme have seen the most protracted involvement of the High Representatives of the European Union in a high-profile policy case. This article traces the evolution of the High Representatives’ participation in the negotiations, from the first contacts with the E3 (Germany, France and the United Kingdom) in 2003 to the adoption of the Joint Comprehensive Plan of Action in 2015. It focuses on the institutional role the High Representatives played in relation with the directoires leading the talks with Iran – first the E3 and, since 2006, E3/EU. In this context, it examines the personal and organisational factors that affected the influence each of the three High Representatives (Javier Solana, Catherine Ashton and Federica Mogherini) had in regard to the directoires. The analysis distinguishes specifically between the phases before and after the 2009 Lisbon Treaty. The article shows how similar personal qualities of the three High Representatives in terms of problem-solving and trust-building gave them political capital that enabled them to adopt a fairly constant role as bridge-builders within the directoires and between the directoires and other actors. The reforms of the Lisbon Treaty had only a minor impact.  相似文献   
74.
This paper describes the results of using 3D visualization (3DV) in sustainable tourism planning (STP) during the Comcot project in Estonia. Organizers were interviewed on the characteristics of 3DV for STP and on how participants were involved in discourse using 3DV. The study describes experiences from the Setu, Maidla, and Võrtsjärv lake regions of Estonia. The content analysis of the interviews suggested that the precise selection of visualization objects, detalization levels, and user interface characteristics may significantly influence the quality of STP sessions and help to optimize time, financial, and human resources allocated for a project. The coherent design of the 3DV tool and the neutral moderator positively affect the level of participant involvement in STP and support a trusted platform for community decision making.  相似文献   
75.
目的采用激光扫描深度图像法和CT影像法,制作颅骨模型,并建立无身源颅骨模型数据库。方法收集各省(区)送检的59例无身源颅骨样本,采用三维激光扫描仪进行颅骨深度图像的采集;采用多排螺旋CT进行颅骨断层影像数据的采集。分别经处理后建立颅骨三维模型。利用3D打印技术实现数字颅骨模型的实体复制。建立具有颅骨信息查询和三维模型显示的无身源颅骨模型数据库。结果采用深度图像法可以获得颅骨的外表面模型,且通过调整扫描仪的参数使细节特征更清晰。采用CT断层影像法可以重建颅骨的内、外部结构,且对于牙齿具有更好的重建结果。建立数据库并将59例无身源颅骨样本信息和三维模型纳入数据库。结论三维建模和3D打印技术可实现对颅骨的重建和模型复制。无身源颅骨数据库的构建,可实现存储和管理颅骨样本的各类信息和三维数据,有助于查询和信息共享,对法医学实践有积极的应用价值。  相似文献   
76.
目的观察急性乙醇中毒大鼠脑皮质α-突触核蛋白(α-synuclein,α-syn)表达及神经细胞凋亡的变化,探讨乙醇对神经细胞损害的机制。方法用50%乙醇溶液灌胃方法制作大鼠急性乙醇中毒模型。采用免疫组织化学染色技术和图像分析方法观察大鼠急性乙醇中毒后1 h、3 h、6 h、12 h脑皮质内α-syn和caspase-3的表达。测定阳性细胞数和平均光密度值,分析其变化趋势,并进行方差分析和t检验。结果急性乙醇中毒组大鼠脑皮质α-syn染色阳性细胞数和平均光密度值均呈上升趋势,6 h达到峰值,12 h略有下降,但仍高于1 h、3 h组。中毒后12 h以内,大鼠脑皮质的caspase-3阳性细胞数和平均光密度值均呈逐渐上升趋势。结论急性乙醇中毒后脑水肿、缺氧引起α-syn异常聚集可能参与乙醇中毒后早期神经细胞凋亡过程。  相似文献   
77.
3G预期下的移动市场结构必定是三个寡头的竞争,在这种条件下,传统NPV和实物期权方法由于没有考虑竞争对手策略互动的影响,而不适用于3G项目投资决策分析。因此,在分析3G项目投资期权价值和博弈特征基础上,利用带跳的几何布朗运动来模拟市场不确定性和技术进步、政府规制等非市场不确定因素,从而确定领先者和追随者的价值函数及临界值,构建领先者和追随者的双寡头期权博弈模型。  相似文献   
78.
应用RT-PCR技术扩增柔嫩艾美耳球虫哈尔滨株子孢子表面抗原3-1E基因,再克隆至质粒载体pMD18-T中,获得重组质粒pMD18-T-3-1E,采用EcoR I+Hind III双酶切法及PCR扩增鉴定正确后,将3-1E基因cDNA目的片段亚克隆到原核表达载体pET-32a(+)中,获得重组质粒pET-32a-3-1E,用EcoR I+Hind III双酶切法及DNA测序证明cDNA序列完全正确.表达蛋白的SDS-PAGE分析表明,表达产物与预期大小(36.47 ku)一致,为可溶性表达.对诱导时间以及IPTG浓度的优化结果表明,当诱导6 h且IPTG浓度在0.8 mmol/L时表达量最大.Western-blot分析表明,表达的蛋白可被感染柔嫩艾美耳球虫鸡的阳性血清特异性识别.将重组3-1E蛋白纯化后分为肌注蛋白组和肌注蛋白加弗氏完全佐剂组免疫AA鸡,通过计算抗球虫指数检测其保护力.结果显示,肌注重组蛋白组与肌注重组蛋白加弗氏完全佐剂组均能刺激鸡体产生一定的免疫反应,对柔嫩艾美耳球虫感染产生有力的保护,其中后者优于前者,表明该重组3-1E蛋白具有研制成亚单位疫苗的潜力.  相似文献   
79.
There is currently no published empirical evidence‐base demonstrating 3D printing to be an accurate and reliable tool in forensic anthropology, despite 3D printed replicas being exhibited as demonstrative evidence in court. In this study, human bones (n = 3) scanned using computed tomography were reconstructed as virtual 3D models (n = 6), and 3D printed using six commercially available printers, with osteometric data recorded at each stage. Virtual models and 3D prints were on average accurate to the source bones, with mean differences from ?0.4 to 1.2 mm (?0.4% to 12.0%). Interobserver differences ranged from ?5.1 to 0.7 mm (?5.3% to 0.7%). Reconstruction and modeling parameters influenced accuracy, and prints produced using selective laser sintering (SLS) were most consistently accurate. This preliminary investigation into virtual modeling and 3D printer capability provides a novel insight into the accuracy of 3D printing osteological samples and begins to establish an evidence‐base for validating 3D printed bones as demonstrative evidence.  相似文献   
80.
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