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1.
数字化人体   总被引:3,自引:0,他引:3  
Zhang Z  Xu YZ 《生理科学进展》2003,34(2):147-149
人体结构的三维成像构造或数字化人体的概念是在医学领域提出来的。利用三维或高维内科成像将人体组织的事件储存为一个三维数据库,再利用计算机技术将人体或人体的组织构建成三维的图像。这样就可以在数字化的人体中进行对真正人体或人体的组织的回顾性观察和分析,而且,这种操作通过现代的计算机网络系统可以远程进行。  相似文献   

2.
自动三维度量学及在人体头面部测量中的应用   总被引:3,自引:1,他引:2  
金观昌  高柠 《人类学学报》1990,9(2):164-167
本文叙述一种新的无需参考物体或平面的自动三维度量学测量系统的原理,以及应用这种系统对人体头面部进行测量。  相似文献   

3.
太阳黑子与人体磁场中心   总被引:2,自引:0,他引:2  
  相似文献   

4.
依据生物学课程标准,尝试利用三维虚拟互动技术进行教学设计及引入社会教育资源辅助学校开展课程,并适度扩展教材内容,有效落实教育教学目标。  相似文献   

5.
虚拟森林景观中林火蔓延模型及三维可视化表达   总被引:13,自引:2,他引:13  
传统上的林火模拟通常只选用一种林火模型,用一个简单的椭圆预测林火蔓延时火场各个位置的情况,与现实中火灾蔓延状况相差甚远,而且以往的林火蔓延是基于二维可视化表达,表达信息有限.本系统采用现今运用最广泛的Rothermel模型,利用Huygen原理,并以改进的粒子系统方法三维模拟在不同的风速、坡度下林火在火场不同位置的扩散行为.采用该方法模拟林火扩散行为,不仅能实时显示受灾面积、火势蔓延的方向、火势大小,且能给人以真实感.并将该方法成功地应用于福建漳浦林区.  相似文献   

6.
物体形态的三维测量技术   总被引:6,自引:0,他引:6  
周文莲 《人类学学报》2000,19(4):324-331
人体测量学 (anthropometry)是人类学的一门分支学科 ,主要研究人体测量和观察方法 ,并通过人体整体测量与局部测量来探讨人体的特征、类型、变异和发展规律 (邵象清 ,1 985)。人体测量在医学、人类学、考古学研究中很重要。传统的人类学测量方法是用直脚规、弯脚规、三脚平行规、特殊量角器等专用仪器 ,量度人体或骨骼表面两点间的直线距离或弧线长度 ,以及线、面间的角度。测量的准确度和速度均有一定的局限性 ,而且获得的是一维数据。众所周知人体及人类骨骼为复杂的三维结构 ,一维的数据结果难以真正充分体现人体或骨骼的某些特征 ,为此…  相似文献   

7.
人体位改变对凝血因子某些因素水平的影响   总被引:2,自引:0,他引:2  
目的 :探讨不同体位对凝血因子检测的影响 ,给循证医学和凝血因子检测全面质量控制提供实验室证据。方法 :1 0 5名志愿者经同体配对试验 ,在不同季节分批抽取不同体位、不同时间、同一部位血液 ,在全自动凝血分析仪上与质控品同批分析疑血因子 5项指标。结果 :以卧位为基线与坐位相比 ,各项指标平均改变 7.0 7% ,多者9.33 % ,差别非常显著 (P <0 .0 0 1 )。根据变化百分数大小依次为 :纤维蛋白原 (FIB) ,凝血酶时间 (TT) ,活化部分凝血活酶时间 (APTT) ,凝血酶原时间 (PT) ,国际标准化比值 (INR)。其中FIB、TT、APTT结果升高 ,呈正相关 (r>0 .97) ,而PT、INR则下降 ,呈负相关。改变体位 1 5min内 ,各参数平均恢复到原体位的 95 .2 %。季节、年龄和仪器差别不影响本实验。结论 :人体位改变能引起凝血因子显著生理变异  相似文献   

8.
薛京伦  俞民澎 《遗传》1989,11(1):46-48
一个细胞的全部遗传信息都编码在长长的线状 DNA分子上,构成一个基因组(Genome)。在DNA分 子上排列着各种不同的基因,基因携带着产生所有蛋 白质的遗传信息。在人体基因组内,有些基因是一个个 单独分布的,在基因与基因之间隔着较长的非编码区 域,这些DNA称为间隔DNA (spacer DNA)。有些 基因则紧密排列在一起,形成基因簇(gene clusters), 或称为基因复合体(gene complexes).  相似文献   

9.
为使医学微生物学实验教学与医学人才培养挂钩,尝试引入成果导向教育理念,指导综合性实验项目“临床样本病原微生物检测虚拟仿真实验”建设。围绕学习主体从三方面进行:明确实验教学目标,制定实验项目的预期学习产出;优化实验教学设计,实现预期学习产出;建立形成性考核评价体系,评定学习产出,促进持续改进。实践表明,此教学模式能够夯实医学生的专业知识与技能,激发学生自主学习及科研创新的积极性,提升医学人文精神及职业素养,为培养具有综合实践能力和人文素养的优质医学生提供助力。  相似文献   

10.
《生物磁学》2011,(3):I0003-I0004
2009年肆虐全球的H1N1病毒可能有一个谁都不曾料到的帮凶。一篇发表在12月5日出版的《自然一医学》杂志上的论文表明。数以万计的死亡者可能是被自己的免疫系统杀死的。  相似文献   

11.
Polyclonal antibody was raised to a cloned fragment of human GM3 synthase. Affinity purified R27C1 antibody to the tagged recombinant protein inhibited GM3 synthase activity in human liver and HL-60 cells in a dose-dependent manner. However, the R27C1 antibody did not affect liver sialyltransferase activity towards asialofetuin. We are the first to measure GM3 synthase activity in human liver (194 +/- 60 pmol NeuAc/h per mg protein), which was about 10-fold lower than in phorbol myristate acetate-stimulated HL-60 cells (1353 +/- 573 pmol NeuAc/h per mg protein). On immunoblotting the R27C1 antibody recognized a common protein band in a number of human tissues (liver, brain, atherosclerotic aortic intima, HL-60 cells) with molecular mass of about 60 kD, which is similar to that of the purified GM3 synthase from rat liver. In human liver and aortic intima, the 60-kD band was almost a single band, which makes possible the use of the R27C1 antibody for immunohistochemical studies in these tissues.  相似文献   

12.
Scoliosis is a three-dimensional deformity characterized by coronal, sagittal and axial rotation of the spine. Surgical fusion of the spine is required in severe cases. Assessment of the surgical procedure requires enough accuracy and flexibility to allow planning of individual interventions or implant designs. Conventional 2-D radiography and even 3-D CT scanning have limitations for in-depth analysis of scoliosis that limit the ability to see the three-dimensional deformity and expose the patient to considerable doses of radiation, respectively. Our stereophotogrammetric analysis is able to provide accurate, intraoperative measurement of vertebral movement during surgical manuevres. Stereophoto pairs taken at each stage of the operation and robust statistical techniques can be used to determine rotation, translation, goodness of fit, and overall spinal contour before, during, and after the surgical instrumentation. A demonstration of data available from this system is included.  相似文献   

13.
14.
Light models for vegetation canopies based on the turbid medium analogy are usually limited by the basic assumption of random foliage dispersion in the canopy space. The objective of this paper was to assess the effect of three possible sources of non-randomness in tree canopies on light interception properties. For this purpose, four three-dimensional (3-D) digitized trees and four theoretical canopies – one random and three built from fractal rules – were used to compute canopy structure parameters and light interception, namely the sky-vault averaged STAR (Silhouette to Total Area Ratio). STAR values were computed from (1) images of the 3-D plants, and (2) from a 3-D turbid medium model using space discretization at different scales. For all trees, departure from randomness was mainly due to the spatial variations in leaf area density within the canopy volume. Indeed STAR estimations, based on turbid medium assumption, using the finest space discretization were very close to STAR values computed from the plant images. At this finest scale, foliage dispersion was slightly clumped, except one theoretical fractal canopy, which showed a marked regular dispersion. Taking into account a non-infinitely small leaf size, whose effect is theoretically to shorten self-shading, had a minor effect on STAR computations. STAR values computed from the 3-D turbid medium were very sensitive to plant lacunarity, a parameter introduced in the context of fractal studies to characterize the distribution of gaps in porous media at different scales. This study shows that 3-D turbid medium models based on space discretization are able to give correct estimation of light interception by 3-D isolated trees, provided that the 3-D grid is properly defined, that is, discretization maximizes plant lacunarity.  相似文献   

15.
目的 探索重点学科人力资源现状。方法 对重点学科人力资源进行现状分析。结果 重点学科共有4 059人;年龄在25岁及以上、45岁以下的占71.2%;工作年限15年以下的占69.5%;硕士研究生学历的占47.3%,本科学历的占38.4%;高级职称的占45.7%。结论 重点学科汇集了大量优秀人才,学科成员年龄分布合理,工作年限偏低,学历以硕士研究生和本科为主,职称偏高,重点学科与重点发展学科内部学历、职称构成存在差异。  相似文献   

16.
王成焘  王冬梅  白雪岭  叶铭 《生命科学》2010,(12):1235-1240
该课题利用"中国可视化人"项目研究成果和志愿者的相关数据,建立了人体全身和部分细分部位的骨肌系统生物力学仿真模型。模型可以按真实对象进行改造,并可植入人工关节等植入物。在所建实验平台中,通过运动捕捉系统测得的或人为设计的运动数据,模型可以仿真人体各种行为运动,进行动力学分析,计算关节力、关节力矩和肌肉力。成果集成在所开发的软件CMVHuman1.0中,完成软件注册登记,并建立了产业化服务体系。成果已在临床医学和植入物设计中获得广泛应用,并扩大到体育科学、人体工程学、航空、航天和虚拟士兵等领域。  相似文献   

17.
Gladysvale, a dolomitic cave located near Johannesburg, South Africa, has yielded in the last few years several thousand Plio-Pleistocene mammalian remains, including some hominid teeth and phalanges. The site consists of four large cave chambers, one of which has been heavily eroded and exposed to the surface. During the field seasons of 1996 and 1997 the cave complex was mapped 3-dimensionally using a laser theodolite. Preliminary graphics allowed a direct control of the mapping process in the field. The topographic structure of the site was reconstructed to a digital terrain model and can now be embedded in a comprehensive Geo-Information System (GIS). Mapping the complex topography of a cave site with many overlapping parts is a challenge; as there exists no algorithm for 3-dimensional triangulation, each overlapping surface has to be triangulated separately. A 3-D model, however, is necessary for understanding the complicated formation of the cave and its geological history. It is now possible to record the exact location  相似文献   

18.
19.
Recently published studies suggest thatterahertz pulsed imaging will have applications inmedicine and biology, but there iscurrently very little information about the opticalproperties of human tissue at terahertzfrequencies. Such information would be useful forpredicting the feasibility of proposedapplications, optimising acquisition protocols,providing information about variability ofhealthy tissue and supplying data for studies of theinteraction mechanisms. Research ethicscommittee approval was obtained, andmeasurements made from samples of freshlyexcised human tissue, using a broadbandterahertz pulsed imaging system comprisingfrequencies approximately 0.5 to 2.5 THz.Refractive index and linear absorptioncoefficient were found. Reproducibility wasdetermined using blood from one volunteer,which was drawn and measured on consecutivedays. Skin, adipose tissue, striatedmuscle, vein and nerve were measured (to date, from oneindividual). Water had a higher refractiveindex (2.04 ± 0.07) than any tissue.The linear absorption coefficient was higher formuscle than adipose tissue, as expectedfrom the higher hydration of muscle. As these samples camefrom a single subject, there is currentlyinsufficient statistical power to draw firmconclusions, but results suggest that in vivo clinical imaging will be feasible in certainapplications.  相似文献   

20.
In this study, we explore post-depositional damage observed on Acheulian bifacial tools by comparing two assemblages: a collection of archaeological handaxes which shows pronounced damage marks associated with high energy water accumulation system, and an experimental assemblage that was rolled and battered in a controlled simulation experiment. Scanning the two assemblages with a precise 3-D optical scanner and subjecting the measured surfaces to the same mathematical analysis enabled the development of quantitative measures assessing and comparing the degree of damage observed on archaeological and experimental tools. The method presented here enables the definition of morphological patterns typically resulting from battering and different from intentional controlled knapping. The most important kinds of damage included the formation of deep, random ‘notch-like’ scars on the lateral edges and substantial degrees of damage to the tip of the tools, but minimal damage to the artifact's butt. Quantifying the degree of damage and its location and morphological characters allows us to present a method by which post depositional damage on archaeological tools can be measured.  相似文献   

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