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141.
基于Cavalieri原理的体视学技术经常运用在组织学和病理学的研究中,但是现在,这种技术已经被运用于医学影像学(如CT、MRI、ECT、超声等)的测量。体视学的方法提供了一个非侵入性的、精确的、无偏的、简单的和快速的测量方法。所以该方法在医学影像学的形态计量学的测量中有临床使用价值。而影像资料的定量测量结果则有助于法医学实践。  相似文献   
142.
Abstract: A study was conducted to investigate whether natural magnetite (Fe3O4), which is an abundant mineral in Thailand, could be used as a magnetic powder in the detection of latent fingerprints. Because of the presence of impurities, powdered magnetite is only weakly attracted by a magnet and cannot be used as a magnetic fingerprint powder by itself. Mixing a small amount of magnetite powder with nickel powder greatly enhances the magnetic attraction. A mixture of magnetite powder and nickel powder in a mass ratio of approximately 1:100 was found to be suitable for use as a magnetic fingerprint powder. Fingerprints developed using the magnetite/nickel mixture on nonporous surfaces were found to exhibit good adherence and clarity. Using an automated fingerprint identification system, the number of minutiae detected in fingerprints developed by using the prepared powder on nonporous surfaces was found to be comparable to those detected in fingerprints developed by using a commercial black magnetic powder. The cost is lowered by more than 60%.  相似文献   
143.
胡福文 《学理论》2009,(21):123-124
本文首先论述了高校图书馆顺应“大流通”服务模式的潮流进行图书磁条转换工作的必要性和可行性,然后重点介绍了图书馆适应招投标法有条不紊地组织好该项工作的具体过程,最后强调了做好该项工作需要注意的有关事项。  相似文献   
144.
DNA数据库建设中批量样品不同DNA提取方法的比较   总被引:2,自引:2,他引:0  
目的比较和选择自动化工作平台提取DNA的方法,并用于DNA数据库建设。方法用手工Chelex-100法、Biomek3000自动化工作平台结合Chelex-100法及DNA-IQTM磁珠法对实验室收集的建库滤纸血样进行DNA提取,荧光定量技术对上述3种方法提取的模板DNA进行测定;扩增产物用3100基因分析仪检测并用基因分析软件分析。结果手工Chelex-100法、自动化Chelex-100法及DNA-IQTM磁珠法提取的DNA模板浓度分别为0.593ng±0.131ng/μl、0.579ng±0.096ng/μl、0.447ng±0.056ng/μl;成功率分别为100%、98.9%、99.5%。结论本文建立的自动化Chelex-100法可用于大规模DNA数据库建设。  相似文献   
145.
工作记忆中央执行功能研究新进展   总被引:4,自引:0,他引:4  
中央执行功能是工作记忆系统中最重要却又研究最少的一个成分。对中央执行功能的研究存在神经心理学、认知行为、脑成像,以及计算模拟等多种途径。近年来研究较多的执行功能包括:双任务协调、注意转换、抑制优势反应、记忆刷新等。目前该领域的研究热点是,运用潜变量分析和脑成像等多学科的先进手段,对执行功能的可分离性和结构有效性进行研究。  相似文献   
146.
Cao L  Chen WZ  Zhang LL 《法医学杂志》2011,27(2):139-141
经颅磁刺激运动诱发电位(transcranial magnetic stimulation-motor evoked potential,TMS-MEP)检查是评价中枢神经系统功能的一种神经电生理检查方法,其法医学应用价值已逐步得到一些法医学者的关注。本文综述了TMS-MEP的发展概况、原理、优势以及目前在评价中枢神经系统功能和临床治疗方面的研究和应用进展,探讨了TMS-MEP在法医学中的应用价值,尤其是对中枢神经系统损伤者客观肌力评定的意义。  相似文献   
147.
Human body fluids and materials were evaluated using attenuated total reflectance Fourier transform infrared spectroscopy. Purified proteins, cosmetics, and foodstuffs were also assayed with the method. The results of this study show that the sampled fluids and materials vary in the fingerprint region and locations of the amide I peaks because of the secondary structure of the composite proteins although the C = O stretch is always present. The distinct 1016 cm(-1) peak serves as a signature for semen. The lipid-containing materials (e.g., fingerprints, earwax, tears, and skin) can also be easily separated from the aqueous materials because of the strong CH(3) asymmetric stretch of the former. Blood-saliva and blood-urine mixtures were also successfully differentiated using combinations of peaks. Crime scene investigators employing rapid, portable, or handheld infrared spectroscopic instruments may be able to reduce their need for invasive, destructive, and consumptive presumptive test reagents in evaluating trace evidence.  相似文献   
148.
Abstract: A quantification of T1, T2, and PD in high isotropic resolution was performed on corpses. Isotropic and quantified postmortem magnetic resonance (IQpmMR) enables sophisticated 3D postprocessing, such as reformatting and volume rendering. The body tissues can be characterized by the combination of these three values. The values of T1, T2, and PD were given as coordinates in a T1–T2–PD space where similar tissue voxels formed clusters. Implementing in a volume rendering software enabled color encoding of specific tissues and pathologies in 3D models of the corpse similar to computed tomography, but with distinctively more powerful soft tissue discrimination. From IQpmMR data, any image plane at any contrast weighting may be calculated or 3D color‐encoded volume rendering may be carried out. The introduced approach will enable future computer‐aided diagnosis that, e.g., checks corpses for a hemorrhage distribution based on the knowledge of its T1–T2–PD vector behavior in a high spatial resolution.  相似文献   
149.
150.
Computed tomography (CT) and magnetic resonance (MR) imaging have become important elements of forensic radiology. Whereas the feasibility and potential of CT angiography have long been explored, postmortem MR angiography (PMMRA) has so far been neglected. We tested the feasibility of PMMRA on four adult human cadavers. Technical quality of PMMRA was assessed relative to postmortem CT angiography (PMCTA), separately for each body region. Intra-aortic contrast volumes were calculated on PMCTA and PMMRA with segmentation software. The results showed that technical quality of PMMRA images was equal to PMCTA in 4/4 cases for the head, the heart, and the chest, and in 3/4 cases for the abdomen, and the pelvis. There was a mean decrease in intra-aortic contrast volume from PMCTA to PMMRA of 46%. PMMRA is technically feasible and allows combining the soft tissue detail provided by MR and the information afforded by angiography.  相似文献   
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