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41.
目的探讨高频超声检查在周围神经损伤鉴定中应用的价值。方法收集38例锐器伤、钝挫伤、骨折及撞击造成的单侧肢体外伤病例,应用东芝Aplio 500型彩色多普勒超声诊断仪进行高频超声检查,将其特征性表现与30例正常周围神经的高频超声图表现进行对比分析。结果经高频超声检查,确诊38例周围神经损伤中发生于颈部5例、下肢5例,上肢27例(肘部以上3例、以下24例)。损伤类型包括卡压性损伤8例、创伤性神经瘤28例、神经完全断裂2例。特征性表现为:卡压性损伤神经受压处变细,近端神经节段性增粗;创伤性神经瘤与神经干相连的梭形增粗段,增粗段神经外膜的线性强回声中断,内部回声紊乱;神经完全断裂表现为神经外膜强回声线与神经纤维低回声束完全中断,断端两侧均呈梭形瘤样改变。结论高频超声能够明确周围神经损伤类型及发生节段,可为法医学人体损伤程度鉴定提供有价值的参考依据。  相似文献   
42.
目的制备标准分子量DNA片段混合物。方法选取pMD18-T载体部分序列作为插入片段,设计引物,制备包含不同大小的标准分子量片段的克隆。大量培养细菌提取质粒,用双酶切、连接荧光接头的方法制备不同大小的带有荧光的标准分子量片段,混合,纯化,最终获得标准分子量片段混合物(内标)。结果用分子克隆方法制备出具有实用性的标准分子量片段混合物,其单个标准分子量片段大小分别为80bp、124bp、194bp、224bp、254bp、304bp、349bp、399bp、424bp、454bp。并且这些标准分子量片段混合物可以准确地对DNATyper15试剂盒的扩增产物进行检测。结论应用该方法制备了能满足研究和实验室要求的标准分子量片段混合物,为DNA分子量标准物标准品的制作提供了一种新的方法。  相似文献   
43.
目的探讨心肌缺血-致命性心动过缓大鼠血清代谢特征。方法制作心肌缺血-心动过缓-死亡(myocardial ischemia-bradycardia-sudden cardiac death,MI-B-SCD)大鼠模型,以假手术组为对照组,应用气相色谱质谱联用仪检测死后血清代谢谱,结合代谢组学策略分析血清代谢特征。结果 MI-B-SCD大鼠血清代谢轮廓与对照差异显著。与假手术组相比,MI-B-SCD大鼠血清赖氨酸、鸟氨酸、嘌呤、丝氨酸、丙氨酸、尿素、乳酸含量明显升高;琥珀酸、棕榈酸、酮己二酸、甘油醛、己烯二酸、辛二酸含量明显下降,其中多种差异代谢物之间存在相关性。结论 MI-B-SCD大鼠血清代谢显著改变,赖氨酸与嘌呤有较高的诊断MI-B-SCD价值,可望为心源性猝死的法医鉴定及临床防治提供参考。  相似文献   
44.
甲基苯丙胺(MA)的毒性作用与多巴胺系统有密切关系,而大量研究表明胶质细胞源性神经营养因子(GDNF)是一种有效的多巴胺能神经营养因子,本文综述GDNF对多巴胺能神经元保护功能机制及用于治疗MA依赖的研究进展,以期为相关研究和应用提供参考。  相似文献   
45.
目的建立腭皱法医学同一认定数字化系统并对其进行效果评价。方法在标准条件下获取腭皱的数字图像,对腭皱信息都进行采集、降噪、增强、分割、特征提取、边缘检测、信息匹配等处理,运用Matlab软件研制腭皱法医学同一认定系统,并进行效果评价。结果本研究成功建立腭皱法医学同一认定数字化系统,从匹配结果来看,正确率达到100%。结论腭皱法医学同一认定数字化系统的建立,为同一认定提供一种新的方法和途径。  相似文献   
46.
Accurate age estimates of immature necrophagous insects associated with a human or animal body can provide evidence of how long the body has been dead. These estimates are based on species-specific details of the insects’ aging processes, and therefore require accurate species identification and developmental stage estimation. Many professionals who produce or use identified organisms as forensic evidence have little training in taxonomy or metrology, and appreciate the availability of formalized principles and standards for biological identification. Taxonomic identifications are usually most readily and economically made using categorical and qualitative morphological characters, but it may be necessary to use less convenient and potentially more ambiguous characters that are continuous and quantitative if two candidate species are closely related, or if identifying developmental stages within a species. Characters should be selected by criteria such as taxonomic specificity and metrological repeatability and relative error. We propose such a hierarchical framework, critique various measurements of immature insects, and suggest some standard approaches to determine the reliability of organismal identifications and measurements in estimating postmortem intervals. Relevant criteria for good characters include high repeatability (including low scope for ambiguity or parallax effects), pronounced discreteness, and small relative error in measurements. These same principles apply to individuation of unique objects in general.

Key points

  • Metrological rigour can increase in forensic entomology by selecting measurements based on their metrological qualities.
  • Selection of high-quality features for morphological identification of organisms should consider these criteria: (1) pronounced discreteness of features (minimising group overlap or maximizing interval); (2) high repeatability of assessment (such as symmetrical width rather than asymmetrical length); (3) small relative error in measurement (selecting the physically largest continuous rigid feature for measurement).
  • These metrological principles also apply to individuation of unique objects in general.
  相似文献   
47.
由于症状表现的主观性以及当前客观检查方法所能提供证据的匮乏,加之赔偿伴生的症状伪装和夸大等问题,脑震荡后综合征患者的伤残评定鉴定意见一致性不高.在人体损伤赔偿纠纷中,脑震荡后综合征患者的伤残评定成为法医精神病鉴定的争议点和难题.通过对脑震荡及相关术语变化、脑震荡后综合征的发生率、症状表现及诊断标准、脑震荡后综合征客观评...  相似文献   
48.
Recently, cloud point extraction (CPE) coupled with back extraction (BE) has been suggested as a promising alternative to liquid-liquid extraction. In CPE, non-ionic surfactants in aqueous solutions form micelles and the solution becomes turbid when heated to the cloud point temperature. Microwave- or ultrasonic-assisted BE can be performed after CPE and before injection of the sample for instrumental analysis by ultraviolet-visible spectroscopy, high-performance liquid chromatography, gas chromatography, gas chromatography-mass spectrometry, or liquid chromatography-mass spectrometry. This article reviews selected published scientific research on the application of CPE-BE to the determination of alkaloids, drugs and organophosphorus compounds from several complex matrices. This method could be scaled-up for use in forensic science.  相似文献   
49.
Virtual anthropology (VA) is based on applying anthropological methods currently used to analyse bones to 3D models of human remains. While great advances have been made in this endeavour in the past decade, several interrogations concerning how reliable these models are and what their proper use should be remain unanswered. In this research, a fundamental assumption of VA has been investigated: if the way we perceive and apply an anthropological method is truly similar when looking at bones macroscopically and through various 3D media. In order to answer, 10 skulls of known age and sex were scanned using a computed tomography (CT) scanner and a 3D surface scanner. Two observers separately applied a defined staging method to eight suture sites on these skulls, first looking at the bone macroscopically, then at the 3D surface scan, and finally on the CT scan. Two rounds of observation were carried out by each observer. Intra- and inter-observer error were evaluated, and two sample t-tests used to evaluate if the different types of medium used yielded significantly different observations. The results show a high degree of inter-observer error, and that data obtained from 3D surface scans differ from macroscopic observation (confidence level 95%, P ≤ 0.05). CT scans, in these settings, yielded results comparable to those obtained through macroscopic observations. These results offer many possibilities for future research, including indications on the kind of anthropological methods and anatomical landmarks that might be reliably transferable to the virtual environment. All current methods used in traditional anthropology should be tested, and if they prove unreliable, new techniques to analyse bones from virtual models should be developed.

Key points

  • Large discrepancies between observation on dry bones and computer-generated 3D models (surface scans or CT scans) could lead to the re-evaluation of the suitability of traditional anthropological methods for application on 3D models.
  • This preliminary study evaluates whether macroscopic, 3D surface scans, and CT scans viewings generate different observations.
  • The results indicate that the data are not always coherent across all three media of observation.
  • Explanations include the aspect given to the bone by the 3D software, differences between handling bones in real life versus on a computer, and level of expertise of the observers.
  相似文献   
50.
目的 明确薄层螺旋CT扫描及其图像后处理功能对肋骨骨折的诊断价值.方法 取2018年在本鉴定所进行肋骨骨折摄片复查的被鉴定人为研究对象,年龄为41~80岁,共计125例,所有对象均在本鉴定所进行薄层螺旋CT扫描,根据现场CT影像学检查进行图像后处理并作出诊断,采用卡方检验对相关数据进行分析.结果 本所复查的案例中,64...  相似文献   
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