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1.
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   

2.
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   

3.
目的 探讨数字医学技术在复杂髋臼骨折复位及手术模拟中的应用。 方法 采集1例髋臼骨折患者的骨盆CT图像,在Mimics 14.01软件上进行三维重建,并利用Geomagic Studio 11.0软件进行骨折的复位和内固定的手术模拟,提出手术指导方案。术后三月再次采集患者骨盆CT图像,三维重建后与术前设计进行比较,评价应用数字技术开展复杂髋臼骨折的术前设计的效果。 结果 根据Tile分型:该病例为C2-3型。Mimics软件重建的骨盆三维模型可准确反映复杂性髋臼骨折的三维立体结构,利用Geomagic软件移动骨折碎片,进行骨折复位,并精确测量出相关的各项数据和进行内固定的放置设计。术后随访钢板与螺钉非常接近术前设计的位置。 结论 应用数字医学技术有助于直观地显示骨盆内部情况并明确分型,并能实现骨折复位及内固定模拟等操作,实现复杂髋臼骨折的术前设计,提高了手术精确性。  相似文献   

4.
背景:有限元数值模拟力学实验方法是对人体进行生物力学结构研究的有效手段。 目的:建立正常6岁健康儿童肱骨的三维有限元模型。 方法:使用某6岁儿童志愿者的人体CT数据,导入到Mimics 10.01软件中,应用阈值分割的方法进行肱骨三维重建。运用Geomagic Studio 12.0对模型表面进行表面优化处理及曲面片的划分,然后使用TrueGrid软件进行网格划分,最后对其进行材料属性赋值,完成有限元模型的构建。施加边界条件及约束,模拟肱骨的三点弯曲试验,输出模拟结果。 结果与结论:建立完成的肱骨有限元模型包括3 024个节点,8节点六面体单元1 875个,实验分别加载0.01 m/s和3 m/s的动态载荷,肱骨中部均发生断裂,载荷-位移曲线与尸体试验结果近似。模拟结果显示,儿童肱骨的有限元模型仿真结果与尸体试验结果较为接近,有限元仿真法可以很好的模拟人体骨骼的物理特性。  相似文献   

5.
Mimics和Geomagic辅助下建立固定义齿的有限元模型   总被引:2,自引:0,他引:2  
目的建立固定义齿的三维有限元模型,为后续的牙周组织的生物力学分析提供数字模型。方法利用Mimics医学影像三维重建软件和Geomagic studio逆向工程软件对CT图像进行处理,并运用UG NX进行实体建模及有限元网格划分。结果建立了包含牙槽骨、基牙、牙周膜、固定义齿的三维有限元模型。结论直接运用牙齿原始数据建模,一定程度上可以避免数据丢失,减少模型失真,所得模型具有较好的几何相似性。  相似文献   

6.
目的:探讨使用Mimics软件构建包含皮肤、肌肉、脂肪以及骨骼的复杂三维人体模型的方法及意义。方法:利用MRJ(MagneticResonanceImaging)切片通过MIMICS软件分别建立人体骨骼、肌肉、脂肪、皮肤等几何面模型,准确表达人体组织和器官的复杂几何结构;将组织和器官的几何面模型导入到MAGICS中进行面网格划分,通过ANSYS软件将面网格转化为体网格,得到人体各器官和组织的三维几何体模型;进而给骨骼、肌肉、脂肪、皮肤分别赋予材料特性(弹性模量和泊松比等),可以模拟真实人体组织和器官的物理属性。结果:利用MIMICS的布尔运算将各部分组织和器官进行组装,得到人体复杂结构的三维实体模型。结论:与目前常用的基于几何学的人体模型建模方法相比,使用该方法建立的三维实体模型可以完全模拟人体器官和组织的真实结构,等效程度高、建模速度快。所建立的数学模型可以直接用于3D打印、模具制造及等效假人的运动学和力学分析。广泛应用于医学、人机工程学等领域。  相似文献   

7.
目的 探讨基于健侧三维数字解剖结构逆向工程个体化计算机辅助设计桡骨头假体的方法以提供临床精确置换。 方法 采用GE Speed Light 16排螺旋CT薄层扫描健康成人1例双侧肘关节,排除桡骨头疾患,获取CT扫描dicom数据导入Mimics10.0软件三维重建肘关节。提取左健侧桡骨近端三维模型经镜像模拟右患侧桡骨近端,再经编辑处理分割为头颈两部分。利用Mimics10.0软件测量颈段髓内径、长度参数构建假体柄。桡骨头模型导入Geomagic studio 12软件模拟软骨加厚处理,导入假体柄模型生成头柄部实体。按解剖特点虚拟组装头柄部件,实现患侧桡骨头假体的逆向工程。 结果 依据健侧肘关节CT影像数据,利用Mimics和Geomagic studio软件,进行三维重建,编辑,测量和反求,可实现个体化桡骨头假体设计和头柄部件的虚拟组装成型。 结论 基于健侧桡骨数字解剖的逆向工程为个体化桡骨头假体的研制提供了一个有效的方法。  相似文献   

8.
背景:在上颌无牙颌种植体支持式固定修复治疗中,上部支架结构材料的选择及不同远端种植体植入方式的设计密切影响着全口种植修复体的长期稳定性。目的:采用三维有限元方法,综合研究3种材料的上部支架及2种固定种植设计方案对上颌种植固定修复生物力学的影响。方法:根据1名健康成人正常颌的锥形束CT资料,采用Mimics软件分离上颌骨及上颌牙列三维实体模型,利用Geomagic Studio软件结合具体的模型参数构建无牙上颌全牙弓种植固定义齿的三维有限元模型。依据上颌后牙区远中种植体植入方式设计的不同,建立两种方案模型:方案1,按照临床常规应用的“All-on-4”设计,即2个种植体垂直植入上颌骨的双侧侧切牙区,另2个种植体则倾斜30°植入到双侧第二前磨牙区;方案2,即2个种植体垂直植入上颌骨的侧切牙区,后牙区采用2个短植体垂直植入双侧第二前磨牙区;在两种方案设计中使用3种材料(钛、氧化锆及聚醚醚酮)分别对上部支架结构进行赋值,得到6个模型,随后对比分析在斜向加载力方向下种植体、周围骨组织及上部支架结构的生物力学效果。结果与结论:(1)无论采用何种材料的上部支架,在两种无牙颌种植固定修复方案设计下,每...  相似文献   

9.
背景:复杂胫骨平台骨折一直是创伤骨科的难题,全面的修复前评估及合理的修复前规划是临床手术的关键。 目的:探讨三维重建及虚拟手术技术在复杂胫骨平台骨折修复前评估和修复前规划中的应用价值。 方法:修复前将30例胫骨平台骨折患者CT扫描图像数据导入Mimics 13.0软件,建立复杂胫骨平台骨折三维数字化模型,对胫骨平台骨折模型进行三维数据测量,按胫骨平台三柱分型进行重新分型,在三维数字化模型上进行开窗、骨块复位、植骨的虚拟手术。 结果与结论:重建的胫骨平台骨折三维数字化模型可准确反映出骨折特点,并可进行任意角度旋转观察,可以准确的进行三柱分型。Mimics13.0软件施行的胫骨平台骨折开窗、复位、植骨的虚拟手术可以逼真模拟临床手术,并且有效估算植骨量。结果证实,三维重建及虚拟手术技术有利于复杂胫骨平台骨折的修复前评估及规划,应该作为修复前准备的常规项目。  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.
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   

12.
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   

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.
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   

16.
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   

17.
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   

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.
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   

20.
Zusammenfassung Der Einfluß von verschiedenen Nahrungsmitteln auf Methoden zur Bestimmung von Adrenalin (AD), Noradrenalin (NA), Vanillinmandelsäure (VMS), Metanephrinen (MN), Homovanillinsäure (HVS) und 5-Hydroxyindolessigsäure (5-HIE) im 24 h-Harn zur Diagnose des Phäochromozytoms bzw. Karzinoid-Syndroms wurde untersucht. Die in die Untersuchung einbezogenen Nahrungsmittel waren: Tee, Kaffee, Mandeln, Ananas, Käse, Walnüsse, Vanillepudding, Bananen, Tomaten und Milchschokolade. Außerdem wurde der Einfluß des Zigarettenrauchens auf die Bestimmung von AD, NA, VMS und MN untersucht.Walnüsse führten zu einer starken Erhöhung der 5-HIE-Ausscheidung. Bananen erhöhten die Ausscheidung von AD, NA, VMS, MN und 5-HIE. Kaffee und Ananas bewirkten eine geringe Zunahme der MN-Werte. Rauchen von 20–30 Zigaretten/Tag beeinflußte keine der vier Variablen.Wenn die beschriebenen Methoden benutzt werden, sollte lediglich auf den Verzehr von Bananen und Walnüssen vor und während der Harnsammelperioden verzichtet werden, da die oberen Normgrenzen im Harn überschritten werden könnten. Ein Verzicht auf Kaffee und Ananas in normalen Mengen ist nicht erforderlich. Es besteht kein Anlaß, weiterhin die bisherigen umfangreichen Restriktionen der übrigen Nahrungsmittel beizubehalten.  相似文献   

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