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1.
目的 介绍一种标准截面形状定制型股骨柄假体结构以及自行开发的设计方法。方法首先利用DICOM格式的患者股骨CT图像,重建患者股骨近端模型;根据重建出的患者股骨近端模型构建股骨柄假体匹配段矩形的截面边界,并在矩形截面边界内用简单的线条初步构建出假体的截面轮廓曲线;利用股骨近端模型对初步设计出的股骨柄假体进行验证,并通过调整设计参数使最终设计出的个性化股骨柄假体与患者股骨髓腔相匹配。结果 定制型人工髋关节股骨柄假体采用标准截面形状,便于快速设计出个性化假体,而且设计操作简单。参数化程序设计大大降低了个性化股骨柄假体的设计工作量。结论 标准截面形状定制型股骨柄假体的设计将有助于提高定制型人工髋关节置换手术的成功率,促进定制型股骨柄假体在临床上的应用,进一步提高患者的生活质量。  相似文献   

2.
目的 介绍定制型髓腔锉的设计与加工方法。方法 根据相应的定制型股骨柄假体的三维模型设计髓腔锉,在计算机辅助设计(CAD)软件中,通过截除、拉伸及偏移面等操作构建出髓腔锉三维模型。采用计算机辅助制造(CAM)技术加工出定制型髓腔锉。采用本研究的CAD及CAM方法,分别为实验及临床试用设计加工了定制型髓腔锉。结果 实验及临床试用的定制型髓腔锉被用于切削相应的尸体股骨腔及患者股骨腔,植入定制型假体以后,通过分析发现假体与股骨腔匹配较好。结论 采用该研究方法设计加工定制型髓腔锉,将能够提高植入定制型股骨柄假体的成功率,将减少定制型股骨柄假体在患者股骨腔中松动的风险,能够促进股骨松质骨长入假体表面来固定假体。  相似文献   

3.
目的研究基于标准X线片的定制型股骨柄设计与加工的方法。方法开发设计假体的软件,其中包括X线片的扫描,股骨腔的获得,假体设计,匹配程度分析,以及绘制二维加工图。利用CAM技术,可以加工设计出所需要的假体。结果在普通机床上加工出股骨柄假体,临床反映股骨柄假体与患者股骨骨髓腔匹配较好。结论临床结果以及理论分析均表明本文介绍的设计与加工股骨柄假体的方法切实可行。  相似文献   

4.
假体松动是目前导致人工髋部假体置换术失败的主要原因。人类股骨上段骨髓腔大小形状差异显著,以致通常设计的髋假体柄在多数情况下不能与骨髓腔形成解剖匹配,接触面小,假体-骨界面应力分布不合理,显著影响假体-骨结合面的稳定性。近几年,按人配制的定制型人工髋假体的研究应用已受到重视。本文介绍发展定制型人工髋假体的依据、定制型人工髋假体的设计研究与临床应用以及定制型假体尚有待解决的问题。  相似文献   

5.
正常股骨近端CT测量及其临床意义   总被引:6,自引:0,他引:6  
目的:通过CT测量正常国人股骨大体形态参数,为假体设计提供解剖学理论依据。方法:60例国人进行股骨近端CT扫描,利用医学图像处理软件对股骨头直径、offset、头位置、颈干角、皮质厚度及闪烁系数(canal flare index,CFI)等参数进行测量、比较。结果:①小转子区域,均可见到自后内侧股骨距部突出的皮质骨样板状结构,对于维持生物固定型假体的稳定起着十分重要的作用;②股骨参数与白种人相比较,在offset、股骨头中心位置及颈干角等参数间存在明显差异(P<0.01);③截骨平面股骨内径与股骨近端及峡部内径有很强的相关性;④年龄与皮质厚度有强的相关性(r=0.6601,P<0.01),随着年龄增长,髓腔内径逐渐增大;⑤干骺闪烁系数(metaphyseal canal flare index,MCFI)对于股骨近端形态变化的描述更为合理。结论:股骨形态复杂多样,有必要设计符合国人的假体,提出与假体相关的设计理念。  相似文献   

6.
目的探讨抛光型股骨柄假体在老年股骨颈骨折假体置换中的应用。方法使用双锥面高抛光股骨柄假体固定治疗老年股骨颈骨折患者63例,股骨假体固定采用第二代骨水泥技术,分析其临床效果。结果术后随访3个月,根据髋关节X线片。所有患者均无髋关节脱位发生。双下肢长度差异为(3.1±1.2)mm。术后3个月髋关节Harris评分为(86±10)分。结论抛光型股骨柄假体通过其在假体设计和假体固定上的改进,可以比较好地解决老年人股骨颈骨折假体置换中所遇到的假体固定闲难等问题。  相似文献   

7.
目的 提出一种组合式个性化人工膝关节假体结构,解决膝关节股骨肿瘤保肢手术由于截骨位置差异性较大,很难采用标准型人工膝关节假体满足个性化需求的问题。方法 首先将患部关节区域CT数据进行三维重建,并利用MRI增强扫描技术建立肿瘤的三维模型,再通过肿瘤模型与患部关节模型进行位置匹配,在三维模型上确定手术截骨位置,根据截骨尺寸设计个性化的股骨柄与标准股骨髁假体进行有效组合,形成一种组合式个性化人工膝关节假体。结果 根据本文设计方法的结果加工成型,骨科临床医生分析膝关节假体结构与人体膝关节生理结构相符,达到个性化假体设计要求,能够重建患者膝关节功能。结论 这种膝关节假体结构有利于降低个性化膝关节假体设计加工成本,缩短设计加工周期,有望提高患者生命质量。  相似文献   

8.
背景:人体股骨髓腔具有扭转的解剖结构,如果股骨髓腔的扭转结构被复制到假体的柄体上,当假体插入髓腔并在假体上加载力时,假体将加载的力转换成股骨髓腔对柄体的扭转力并将该力传递到股骨近端。目的:优化股骨近端的力传递,避免假体近端应力遮挡。方法:利用人股骨标本的CT图片重建股骨髓腔的3D模型,将该3D模型作为柄体的设计模型。将定制式柄体模型与标准假体的近端模型拼合,形成定制式假体。采用机器人磨削技术制作定制式假体,并将定制式假体与标本股骨髓腔匹配。利用有限元仿真和实验方法分析假体上加载的力与假体近端扭转微动的关系。结果与结论:仿真和实验结果表明,股骨髓腔与柄体匹配的扭转结构,可有效地将假体上加载力以扭转力的形式传递到股骨近端,假体近端的扭转微动与柄体的微动相关,而柄体的微动可通过改变柄体与髓腔的匹配区大小得到控制。  相似文献   

9.
背景:生物型股骨柄假体无菌松动是全髋关节置换失败的主要因素,减少无菌松动的先决条件是增加股骨柄假体在股骨髓腔中的填充率。目的:得到定制式股骨柄假体在髓腔中的填充率,验证计算机辅助设计/计算机辅助制造/工业机器人加工(CAD/CAM/Robotic)集成方法和机器人磨削的有效性。方法:利用CT数据重建股骨髓腔三维模型,在此三维模型基础上设计股骨柄假体的柄体,依据标准直柄股骨柄假体近端模型设计股骨柄假体的其余部分。将设计的股骨柄假体模型导入CAD/CAM/Robotic集成系统生成机器人磨削轨迹,利用该轨迹对股骨柄假体进行磨削加工。将加工好的股骨柄假体与股骨髓腔匹配,分析股骨柄假体在髓腔中的填充率。结果与结论:实验结果表明,定制式股骨柄假体在髓腔中有良好的填充率,髓腔的解剖结构可以阻止股骨柄假体的扭转,获得股骨柄假体在髓腔中的稳定固定。  相似文献   

10.
背景:新一代Tri-Lock BPS型股骨柄假体在原有设计基础上得到进一步改进,目前尚少有报道总结其设计特征及手术技巧。 目的:总结Tri-Lock BPS型股骨柄假体的设计特征及其在全髋关节置换中的应用。 方法:选择Tri-Lock BPS柄行全髋关节置换的患者9例(10髋),其中股骨头坏死8例,创伤性关节炎1例。置换前后的髋关节功能和置换后股骨柄假体的生物学固定分别按Harris标准和Engh标准评定,置换后股骨柄假体的初始固定质量按Healy标准评定,分析透亮线、骨溶解的发生率,分别按Delee和Gruen分区描述髋臼和股骨侧的骨长入,按D’Antonio法测量股骨柄假体的下沉,股区痛则采用目测类比评分10分制评定。 结果与结论:10髋置换后X射线片显示股骨柄假体的初始固定均符合优良标准。凡手术满3个月的患者,髋关节功能(Harris评分)均可恢复至平均92分(85~96分),无主诉存在股区痛,无X射线显示的假体松动征。结果证实,Tri-Lock BPS型假体设计更符合人体解剖特征,髋关节功能恢复快,骨量保留多等优点。  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.
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   

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.
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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