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1.
背景:三维图像重建是开展膝关节虚拟研究的基础。关节周围韧带、软骨、半月板等结构分割重建报道较少。目的:在前期大量膝关节标本解剖研究的基础上,利用CT及MRI数据,三维重建包括关节周围韧带、软骨、半月板等结构在内的膝关节模型。方法:采用1例人体成年膝关节标本CT、MRI薄层扫描数据,导入Mimics 10.01分别三维重建膝关节骨、软骨、韧带及半月板等结构,利用逆向工程软件Geomagic 8进行及图像配准处理。结果与结论:三维重建了包括关节周围韧带、软骨、半月板等结构在内的膝关节模型,为建立相应膝关节有限元模型奠定了基础。  相似文献   

2.
膝关节关节软骨的三维构建   总被引:1,自引:0,他引:1  
目的:构建膝关节关节软骨的三维模型,为开展膝关节数字医学研究进行模型构建的探索。方法:人体成年新鲜膝关节标本1例,行CT、MRI扫描,利用三维重建软件Mimics及逆向工程软件Geomagic对图像进行三维重建及图像配准,构建膝关节骨、关节软骨结构。结果:利用Mimics 10.01软件构建关节软骨的三维模型,并形成骨-关节软骨复合模型,导入Geomagic软件中与CT构建的骨三维模型相配准,再次导入CT影像中进行逐层微修饰,验证关节软骨分割效果。最终建立具有骨、关节软骨的三维膝关节模型。结论:三维图像重建技术与图像配准技术可将CT、MRI图像两者结合起来,发挥其各自优势,构建出形态较好的膝关节三维模型。  相似文献   

3.
背景:国内外已有学者利用不同的方法对人体膝关节进行三维建模,根据各自研究侧重点不同,在方法和最终效果上各有不同。 目的:根据不同模态中膝关节影像的特点,将膝关节建模结果进行配准、融合,为进一步生物力学研究提供一种方便的方法。 方法:采用Mimics V 10.0软件根据膝关节在CT和MR断层图像的特点,选择不同分割算法进行膝关节解剖组织分割,并对不同的分割图像进行三维重建。 结果与结论:基于逆向工程原理,利用虚拟人膝关节连续CT断面图像分别重建出膝关节的骨性结构如股骨、胫骨、腓骨、髌骨;并利用膝关节的连续MRI断面图像重建出半月板、髌韧带、内侧副韧带、前交叉韧带、后交叉韧带等结构,并成功对上述结构进行融合,融合后的三维膝关节模型可以任意角度或单独观察,并可以进行体视学测量。说明通过不同模态图像融合的方法可以建立膝关节的三维模型,为计算机辅助膝关节损伤康复研究奠定基础。  相似文献   

4.
背景:随着现代工业、现代国防以及现代医疗康复产业的发展,仿生设计与制造技术蓬勃兴起,该技术常以各类生物体及其组织为研究对象,模仿其几何外形、力学性能等指标,进而得以逆向设计与制造各类人工合成产品,其中几何外形特别是曲面建模技术的有效仿生是其中的关键一环。目的:以人体膝关节为例探讨曲面建模实践应用技术,建立人体膝关节几何解剖数字化模型,为膝关节生物力学特性的研究提供支持,同时为仿生设计的复杂曲面建模提供了一种有效的教学与研究模式。方法:利用膝关节CT扫描图像和MRI图像,通过医学影像处理技术分别获取骨组织及软组织轮廓的点云数据及其逼近曲线,并分别重建骨组织及软组织的膝关节实体模型。最后基于三维图像配准技术,将各软组织组装配于骨组织实体模型上,形成整体膝关节三维模型。结果与结论:通过3D医学影像技术构建了同时包含各骨组织和韧带、半月板、肌腱等主要软组织在内的膝关节复杂几何曲面解剖数字化模型。  相似文献   

5.
目的 利用三维重建软件进行颌面部骨性结构与血管快速重建探讨其对口腔颌面外科临床的指导意义。 方法 对2例志愿者和2名颌面部骨折患者行多层螺旋CT 头颅血管造影扫描, 层厚0.6 mm, 将Dicom格式数据导入Mimics 10.01和3D-Doctor4.0,对颌面部骨性结构及其周围血管进行快速重建三维模型。 结果 重建的三维模型能清楚显示颌面部骨性结构及其周围血管的详尽立体解剖形态, 所得重建图像逼真, 可观察任意剖面并且多角度变换,显示其空间位置关系和定量测量分析。重建过程简单,无须专业三维重建人员进行操作,且结果可以导入CAD软件,进行快速成模。 结论 利用三维软件进行颌面骨性结构及其周围血管快速重建能为颌面部的手术设计与实施, 提供了快速可靠的形态学依据。  相似文献   

6.
背景:目前使用的保留前后叉韧带的假体仍存在诸多问题。改良和设计保留前后交叉韧带膝关节假体相关的形态测量,特别是胫骨近端未曾见到过详细的报道和研究。 目的:通过对正常膝关节三维数字化模型进行相关的胫骨近端形态学的分析,从而为改良和设计保留前后交叉韧带人工全膝关节假体提供参考。 方法:40例正常志愿者进行膝关节的CT及MRI扫描,然后将膝关节CT、MRI断层影像数据导入Mimics 10.01进行图像分割与三维重建,重建出完整的膝关节三维实体数字化模型后再导入Geomagic Studio 11,在膝关节模型上测量前后交叉韧带在胫骨近端解剖参数,模拟截骨后测量胫骨近端截骨面的解剖参数。 结果与结论:前后交叉韧带总的宽度为(14.94±2.56) mm,性别间比较提示男性需适当增加横向的截骨宽度以避免损伤前后交叉韧带。胫骨髁间棘顶部的长度为(8.02±1.03) mm,底部的长度为(15.19± 1.71) mm,截骨后高度(9.13±0.88) mm,而且此梯形结构位于前后径48%-82%。胫骨截骨面内侧的内外径短于外侧的内外径,内侧前后径大于外侧的前后径,因而保留前后交叉韧带的假体更需要非对称性的设计。  相似文献   

7.
背景:克服传统标本力学分析的不利因素,建立逼真的足部各结构有限元模型,是对足部进行有限元力学分析的重要基础。 目的:建立足部的三维有限元数字模型,为正常足部及足部损伤情况下的有限元力学分析打基础。 方法:对1名健康女性志愿者行双足螺旋CT扫描,将所得图像在Mimics软件中重建三维模型,在Geomagic软件中生成实体模型,最后在Ansys中建立足主要结构的三维有限元数字模型。 结果与结论:实验建立了包括全部骨骼、主要软骨和韧带、皮肤及软组织在内的人足有限元数字模型。利用CT数据及Mimics、Geomagic、Ansys软件可以建立人足全部足骨的三维有限元数字模型,该模型与实际骨骼模型大小、形态一致,并且可以随意旋转,任意角度观看,进行各种测量,可将足部骨骼任意拆分或合并,适合进行生物力学分析。 中国组织工程研究杂志出版内容重点:肾移植;肝移植;移植;心脏移植;组织移植;皮肤移植;皮瓣移植;血管移植;器官移植;组织工程全文链接:  相似文献   

8.
目的探讨基于影像学与解剖学构建颞下颌关节(temporomandibular joint,TMJ)骨骼肌肉系统三维有限元模型的可行性,为TMJ生物力学研究提供建模的新思路。方法采集第2代中国虚拟人男性第23号头颅CT图像、咀嚼肌及TMJ关节盘MRI图像,以DICOM格式导入Mimics软件进行三维重建,再通过Geomagic Studio软件配准模型、优化模型及构建关节软骨和关节囊,最后由ANSYS软件定义各组织的材料属性,建立TMJ骨骼肌肉系统的三维有限元模型。结果建立了一个包含关节盘、关节软骨、关节囊、上颌骨(包括颧骨及鼻骨)、下颌骨、颞骨(包括部分顶骨)、蝶骨、上牙列、下牙列、颞肌、咬肌、翼内肌、翼外肌、颞下颌韧带、蝶下颌韧带及茎突下颌韧带的TMJ骨骼肌肉系统的三维有限元模型。结论根据CT、MRI图像和解剖学,利用Mimics、Geomagic Studio及ANSYS可以精确、可行地构建TMJ骨骼肌肉系统的三维有限元模型。模型更加真实还原TMJ的生物力学环境,为TMJ生物力学研究提供新的建模方法,为临床上TMJ疾病的可视化治疗提供仿真平台。  相似文献   

9.
目的寻求建立颈椎后路手术相关结构数字模型及三维可视化方法。方法取健康志愿者头顶至第3胸椎下缘连续CT/MRI断面图像,Mimics软件对骨骼,肌肉,神经等组织用半自动方法进行分割和重建,MedCAD(医学计算机辅助设计)模块对细小解剖结构重建,三维化显示颈椎后路手术相关解剖结构。结果建立颈椎后路手术相关结构的三维可视化模型,显示骨性结构、颈背部由浅入深4层17组肌肉、4组韧带、C1~T2脊神经后支和颈部浅层肌等解剖结构的位置关系。结论在颈背部三维可视化模型基础上,参照解剖学层次逐层显示该手术相关重要结构,为该手术解剖教学、手术培训提供医疗教学平台。  相似文献   

10.
同时基于个体股骨头坏死患者的X-ray、CT和MRI图像,采用图像配准和融合技术对包含坏死股骨头的髋关节进行三维重建,获取具有高度几何相似性的三维有限元网格模型。选择1例中年女性股骨头坏死患者,分别获取X-ray、CT和MRI三套图像,采用Mimics 13.1和Pro/E 5.1软件分别基于这三套数据建立相关三维实体模型,经图像投影转换后,确定图像之间的匹配点,进行二维图像配准,配准后对成功融合的图像进行三维有限元网格模型显示。建立了具有良好几何相似性的髋关节三维有限元网格模型,包括正常皮质骨、松质骨、关节软骨和股骨头坏死区、断裂骨小梁等六部份,较真实地反映了包含坏死股骨头的髋关节的形态特征及毗邻关系,为进一步的生物力学分析和手术模拟提供了较理想的研究平台。  相似文献   

11.
Renal dysplasia and asplenia in two sibs   总被引:2,自引:0,他引:2  
A family is reported in which two sibs, one male and the other female, both died within 24 hours of birth with enlarged polycystic kidneys. Postmortem histology in the second child showed gross renal dysplasia. In both children the pancreas was enlarged, nodular and cystic but the liver appeared macroscopically normal. In the second child, histological examination confirmed pancreatic fibrosis with cystic dilation of ducts, but showed portal fibrosis with bile duct proliferation in the liver.
This combination of findings is very reminiscent of those in a girl and her brother reported by Ivemark et al. (1959). The children reported here also showed absence or hypoplasia of the spleen, cardiac anomalies and other features of the Ivemark syndrome (Ivemark 1955), a quite different, usually sporadic, congenital disorder. It is suggested that the children described here have a distinct lethal congenital disorder, probably inherited in an autosomal recessive manner.  相似文献   

12.
Over 200 schizophrenic patients belonging to three major and interrelated pedigree complexes have been investigated over the past 30 years in a North Swedish geographically isolated population, presently numbering about 6,000. An intensive investigation of a number of biochemical correlates and genetic markers in a few selected families belonging to one of the major pedigrees has indicated new strategies for the current research program.
Schizophrenia, as defined operationally, is significantly associated with decreased activities of two enzymes (1) blood platelet monoamine oxidase, (2) plasma dopamine-β-hydroxylase, and (3) with the genetic marker Gc2 (group specific antigen). Both enzymes are subject to genetic variation. A positive score for linkage between schizophrenia and low plasma DBH activity has been calculated, but, so far, available data are insufficient for discrimination between linkage and partial contribution of genetically controlled low plasma DBH to the pathogenesis of the disease. Alternatively, both mechanisms could be involved.
As a model for continued research, schizophrenia is explained as based on a double dominant-recessive genotype (Aabb), representing a vulnerability which in about 50 % of cases develops into clinical schizophrenia. It is suggested that the dominant mutation (A) operates on or affects MAO activity, and that the recessive genotype (bb) is instrumental in low variates of DBH activity and very likely such variates within the normal range of physiological variation. Moreover, it is suggested that the combined effects of MAO- and DBH-reduced efficiency on the metabolism of e.g. dopamine could be an essential pathogenic mechanism for the schizophrenic illness which is segregating in this population.  相似文献   

13.
About 1900, modern food selection and processing caused widespread epidemics of the B vitamin deficiency diseases of beriberi and pellagra which, for genetic reasons, often expressed as different diseases ranging from bowel and heart disease to dermatoses and psychoses. But the B vitamins merely help convert essential fatty acids (EFA) into the prostaglandin (PG) tissue regulators and it now turns out that, through hydrogenation, milling and selection of w3-poor southern foods, we have also been systematically depleting, by as much as 90%, a newly discovered trace Nordic EFA (w3) of special importance to primates and sole precursor of the PG3(4) series, even as a concurrent fiber deficiency increases body demand for EFA. Since substrate EFA is processed by many B vitamin catalysts, an EFA deficiency will mimic a panhypovitaminosis B, i.e., a mixture of substrate beriberi and substrate pellagra resembling vitamin beriberi and pellagra but exhibiting as even more diverse endemic disease. This would consitute a second stage of the Modern Malnutrition and explain why some workers now hold the dominant diseases of modermized societies to be new, nutritionally based, pellagraform yet lipid-related and to range, once again, from heart disease to psychosis. It is an assumption that our dominant diseases are unrelated to each other or are merely revealed by our diagnostic acumen and therapeutic success; and that hydrogenating millions of tons of food oils annually, to destroy the rancidity producing w3-EFA, is safe for primates. Extensive beriberiform disease is reported here in 32 typical cases taken from medical practice which responds strikingly to linseed oil supplements (60% w3-EFA) in confirmation of identical results in Capuchins.  相似文献   

14.
15.
There are an estimated over 200 million yearly cases of malaria worldwide. Despite concerted international effort to combat the disease, it still causes approximately half a million deaths every year, the majority of which are young children with Plasmodium falciparum infection in sub-Saharan Africa. Successes are largely attributed to malaria prevention strategies, such as insecticide-treated mosquito nets and indoor spraying, as well as improved access to existing treatments. One important hurdle to new approaches for the treatment and prevention of malaria is our limited understanding of the biology of Plasmodium infection and its complex interaction with the immune system of its human host. Therefore, the elimination of malaria in Africa not only relies on existing tools to reduce malaria burden, but also requires fundamental research to develop innovative approaches. Here, we summarize our discoveries from investigations of ethnic groups of West Africa who have different susceptibility to malaria.  相似文献   

16.
Newton H 《Medical history》2011,55(2):153-182
Sick children were ubiquitous in early modern England, and yet they have received very little attention from historians. Taking the elusive perspective of the child, this article explores the physical, emotional, and spiritual experience of illness in England between approximately 1580 and 1720. What was it like being ill and suffering pain? How did the young respond emotionally to the anticipation of death? It is argued that children’s experiences were characterised by profound ambivalence: illness could be terrifying and distressing, but also a source of emotional and spiritual fulfilment and joy. This interpretation challenges the common assumption amongst medical historians that the experiences of early modern patients were utterly miserable. It also sheds light on children’s emotional feelings for their parents, a subject often overlooked in the historiography of childhood. The primary sources used in this article include diaries, autobiographies, letters, the biographies of pious children, printed possession cases, doctors’ casebooks, and theological treatises concerning the afterlife.  相似文献   

17.
Recent advancements in agricultural biotechnology have created a need for analytical techniques to determine introduced proteins in crops enhanced through modern biotechnology techniques. These proteins are expressed in plant tissues and may be present in food ingredients. Immunoassays are ideally suited for protein detection and may be used as both quantitative and threshold methods. Microplate ELISA and lateral flow devices are two of the most commonly used immunoassay formats for agricultural biotechnology applications. This paper provides general background information and a discussion of criteria for the validation and application of immunochemical methods to the analysis of proteins introduced into plants and food ingredients using biotechnology methods. It is the result of a collaborative effort of members of the Analytical Environmental Immunochemical Consortium. This collaborative effort represents the combined expertise of several organizations to reach consensus on establishing guidelines for the validation and use of immunoassays. Further, the paper offers developers and users a consistent approach to adopting the technology as well as aid in producing accurate and meaningful results.  相似文献   

18.
The preparation steps usually necessary for obtaining ultrathin frozen sections of biological material (chemical prefixation, enclosing, cryoprotective treatment, freezing, sectioning, and post-staining the sections for transmission electron microscopy) are submitted to a critical analysis. The application of cryo-ultramicrotomy, in particularly for cytochemical purposes, is reviewed. Fundamental considerations of chemical prefixation and poststaining are supported by examples from yeast cytology. Furthermore, the efficiency of the cryo-ultramicrotomy (electron optical resolution of ultrastructural details) is demonstrated on yeast cells and protoplasts.  相似文献   

19.
HLA-A,-B,-C,-DRB1 and -DQB1 alleles have been studied in Chimila Amerindians from Sabana de San Angel (North Colombian Coast) by using high resolution molecular typing. A frequent extended haplotype was found:HLA-A*24:02-B*51:10-C*15:02-BRB1*04:07-DQB1*03:02 (28.7%) which has also been described in Amerinndian Mayos Mexican population (Mexico, California Gulf, Pacific Ocean). Other haplotypes had already been found in Amerindians from Mexico (Pacific and Atlantic Coast), Peru (highlands and Amazon Basin), Bolivia and North USA. A geographic pattern according to HLA allele or haplotype frequencies is lacking in Amerindians, as already known. Also, five new extended haplotypes were found in Chimila Amerindians. Their HLA-A*24:02 high frequencies characteristic is shared with aboriginal populations of Taiwan; also, HLA-C*01:02 high frequencies are found in New Zealand Maoris, New Caledonians and Kimberly Aborigines from Australia. Finally, this study may show a model of evolutionary factors acting and rising one HLA allele frequency (-A*24:02), but not in others that belong to the same or different HLA loci.  相似文献   

20.
Starting with the integument, we see many organs are contractile sacs or multiples thereof, which tubes or bags constitute the major part of the entire body. Recognition of this basic unit and its characteristics sheds new light, individually and collectively, on many disorders previously considered unrelated. Muscular tears and perforations develop in the walls of these chambers, being no way peculiar to those organs, wherein, hydrochloric acid occurs. So, it is not necessary to explain the absence of excessive acid from patients who exhibit holes in the gastric, uterine, aortic, duodenal, rectal, pulmonary, retina, and other walls. Muscle, not acid is the great common factor relating idiopathic disorders in the gastrointestinal tract to each other and to similar diseases in other systems. When the units are linked together, the lesions tend to appear as arthropathies, i.e. at the joints. Rephrasing common-place observations, frees us from conventional, conceptual cul-de-sacs. An observation is only as good as its interpretation, so all possibilities must be considered, otherwise, we will remain blinded by our misconceptions.  相似文献   

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