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1.
目的比较经皮骨盆后方张力带钢板和经皮骶髂螺钉固定Denis 3类骶骨纵行骨折的术后稳定性和力学相容性,为不同类型骨折的内固定术式选择提供依据。方法采用第2代中国数字化人体"男性第23号"CT和MRI,构建完整骨盆有限元模型,骶骨Ⅰ、Ⅱ、Ⅲ区纵形骨折伴同侧耻骨上下支骨折的经皮后方张力带钢板内固定有限元模型,以及这3类骨折的经皮骶髂螺钉内固定有限元模型。根据腰骶脊柱三柱加载模式和骶髂关节生理运动模式采用多方案有限元分析及实验验证。结果骶骨Ⅰ区骨折时,张力带钢板组(P组)的后环与前环器械应力均比骶髂螺钉组(S组)明显增加,骶骨位移也增加。骶骨Ⅱ区骨折时,P组后环与前环器械应力均比S组减小,骶骨位移明显减小。骶骨Ⅲ区骨折时,P组后环与前环器械应力以及骶骨位移均比S组明显减小。结论从内固定术后稳定性、骨折愈合的力学相容性及手术操作的安全性等方面考虑,经皮骶髂螺钉比较适合治疗骶骨Ⅰ区纵形骨折的垂直不稳定型骨盆,而经皮后方张力带钢板比较适合治疗骶骨Ⅱ区和Ⅲ区纵形骨折的垂直不稳定型骨盆。  相似文献   

2.
目的在高度仿真的完整骨盆三维有限元模型基础上,模拟使用新设计的解剖型钢板对骶髂关节骨折脱位进行固定,并与普通钢板的模拟固定进行对比,验证和分析新型钢板的性能.方法从CT精确重建髋骨和骶骨模型,采用专门的半自动流线型生物力学有限元网格划分器生成规则的体网格模型,并进一步建立骶髂关节的终板、软骨、关节接触面,和骨盆上的主要韧带组织及耻骨间盘.然后去掉一侧的骶髂关节韧带群模拟骨折脱位,使用新型的骶髂关节解剖型棒-板内固定系统进行固定模拟,同时使用普通钢板替代解剖型钢板建立对比模型,分别进行加载分析受力情况.结果通过使用新的解剖型钢板改进棒一板内固定系统,骶髂关节的最大相对位移值减小了约23%,骨盆主要传承负载区域的最大的应力值降低了约25%.结论新型的解剖型钢板有效地提高了骶髂关节棒-板内固定系统的力学性能,为骨盆骨折的治疗增加了一种更有效的新方法.  相似文献   

3.
骶骨钉治疗骨盆后环损伤的体会   总被引:1,自引:0,他引:1  
目的 探讨采用骶骨钉治疗骨盆后环损伤的疗效及手术指征.方法 2004~2006年采用骶骨钉治疗骨盆后环损伤病人共18例.在C型臂透视下,将骶骨钉经过髂骨、骶髂关节、椎弓根固定到骶1椎体上.结果 18例患者经半年以上随诊,获得良好的治疗效果,优良率达94.4%,无血管、神经、内脏损伤并发症发生.结论 通过对这组患者的治疗,认为骶骨钉治疗骨盆后环损伤具有创伤小,恢复快,费用低的特点,手术指征为:(1)骶髂关节损伤、脱位或骶髂韧带损伤致骨盆不稳定;(2)骶骨骨折不稳定;(3)骶髂关节脱位伴骶骨或髂骨骨折,合并骶髂韧带损伤不稳定;(4)耻骨联合分离(>2.5cm);(5)分离、移位明显的耻骨支骨折伴骨盆不稳定.  相似文献   

4.
目的利用骨盆的三维有限元模型研究外旋应力对骨盆的作用机制。方法 1例健康成年男性志愿者进行PET-CT扫描,结果以DICOM格式输出,在PC机上进行三维重建,建立正常骨盆的有限元模型。对模型施加外旋载荷,经计算得到应力、应变及位移云图。结果水平向后加载500N于左侧髂前上棘,应力沿两条途径传导:一条是向内后方经同侧骶髂关节前部至骶骨上部,另一条是向前方经耻骨支、耻骨联合至对侧耻骨;且骨盆前环受力较大。应变以同侧骶髂关节前下方最大,前方的耻骨联合处应变也较大。位移以受力点同侧髂前上棘处最大,同侧髂骨、坐骨及耻骨支位移均较大。结论外旋载荷易造成耻骨支骨折、骶髂关节损伤,或骶骨压缩骨折。  相似文献   

5.
目的 探讨根据骨盆的形态特点选择不同的内固定手术治疗不稳定型骨盆骨折的临床应用价值。 方法 65例不稳定型骨盆骨折,31例Tile B型骨折经前入路,将耻骨联合或耻骨支复位用重建钢板固定,其中8例合并髂骨骨折经髂窝入路将之复位用重建钢板固定;34例Tile C型骨折的前环损伤均采用与Tile B型骨盆骨折相同的方法处理,后环损伤的固定方法:17例骶骨骨折或骶髂关节脱位之中,复位后在透视引导下从后方经皮骶髂螺钉固定11例,经髂骨的螺栓固定4例,经后路在双侧髂骨后嵴之间用张力带钢板固定2例;9例骶髂关节骨折-脱位之中,经皮骶髂螺钉固定6例,钢板固定3例;8例合并髋臼骨折行重建钢板内固定。 结果 通过对术后骨盆X线测量骨折分离移位的最大距离,根据Matta评分标准:小于4 mm为优,占86.1%(56例);4~10 mm为良,占7.7%(5例);10~20 mm为可,占6.2%(4例);大于20 mm为差(0例)。本组骨盆X线测量结果总优良率为93.8%。 结论 不稳定型骨盆骨折应在血流动力学稳定时尽早根据骨折的类型及骨盆的解剖形态特点选择合理的内固定手术方案。  相似文献   

6.
个性化全骨盆三维有限元建模及骶髂关节骨折脱位模拟   总被引:1,自引:0,他引:1  
目的建立高度仿真的个性化的完整骨盆三维有限元模型,并在此基础上进行骶髂关节骨折脱位的模拟。方法从CT精确重建独立的左、右髋骨和骶骨实体模型,根据髋骨和骶骨的外形特征,利用专门的流线型生物力学有限元网格划分器生成规则的体网格模型,并进一步建立骶髂关节的终板、软骨、关节接触面,和骨盆上的主要韧带组织及耻骨间盘。在建立的完整模型上去掉一侧的骶髂关节韧带群进行骨折脱位模拟,并与正常的情况进行对比。结果建立了高精度的个性化全骨盆的三维有限元模型,包括左右髋骨和骶骨的皮质骨、松质骨,骶髂关节的终板、软骨和带摩擦的关节接触面,韧带包括骶髂骨间韧带、骶髂前韧带、骶髂后韧带、骶棘韧带、骶结节韧带、耻骨上韧带和耻骨弓状韧带,以及耻骨间盘。正常模型的加载模拟和骶髂关节骨折脱位模拟的预测结果均与文献试验生物力学结果相符合。结论利用专门的生物力学有限元建模工具能建立更复杂更精确的三维有限元模型,成为全骨盆生物力学分析研究的平台和基础。  相似文献   

7.
目的探讨应用微创前路钢板固定技术在治疗不稳定骨盆骨折中的应用,并评价其疗效。方法 2009年2月~2016年8月收治20例骨盆骨折的患者,其中男性9例,女性11例,平均年龄38.5岁,按照Tile分型,B型11例,C型9例;骨盆前环损伤类型,单侧耻骨支损伤11例,双侧耻骨支损伤9例;后环损伤类型,骶骨骨折6例,骶髂关节分离8例。骨盆前环骨折采用前路微创双切口髂腰肌下入路钢板固定,合并后环骨折的患者采用骶髂螺钉或钢板固定骶髂关节骨折脱位,并记录术中出血量和手术时间,术后应用Matta标准和Majeed评分系统对骨盆复位和功能恢复进行评价。结果20例患者均获得随访,平均26个月,手术切口一期愈合,前环骨折平均手术时间1h,出血215 m L,没有出现切口感染和神经血管损伤的手术并发症,骨折愈合时间在11周~14.5周,术后骨折复位Matta标准:优17例,良2例,一般1例。术后末次随访时Majeed功能评分:优15例,良3例,一般2例,优良率90%。1例Tile C型骨盆骨折的患者,术前合并骶丛神经损伤,术后骶丛神经没有完全恢复,遗留感觉部分障碍和跛行步态。结论对于不稳定骨盆骨折的患者采用微创髂腰肌下通道入路钢板治疗,重建骨盆前环,具有创伤小,不需显露股神经和血管等结构,手术时间短,出血少,临床疗效满意和手术安全的特点。  相似文献   

8.
目的比较不同固定方法治疗不稳定骨盆骨折的生物力学稳定性,为临床治疗提供参考。方法使用三维有限元方法,建立一侧骶髂关节脱位合并耻骨支骨折的不稳定骨盆骨折模型(Tile C型),前方采用改良Stoppa入路(anterior pelvic Stoppa approach,ASA)、前方经皮入路(anterior pelvic approach,APA)、传统的髂腹股沟入路(anterior pelvic ilioinguinal approach,AIA)、外固定架(anterior pelvic external fixation,AEF) 4种方法固定,后方采用骶髂螺钉固定(sacroiliac joint screw,SIJS)和经皮重建钢板(posterior tension-band plate,PTP)两种方法固定,并比较分析模拟站立状态时8种不同组合固定方法下骨盆环Von Mises应力、应变分布情况。结果加载竖直方向500 N载荷后,在前方内固定组中,骨折处的最大应力均被限制在10 MPa以下。内固定前、后方的最大应力分布ASA AIA AEF APA;在相同应力下,平均位移为ASA AIA AEF APA。而在后方固定组中PTP组在骶髂关节处及内固定后方的最大应力明显小于SIJS组,且在骶髂关节和骨折处的最大总位移和垂直位移也比SIJS组要小。结论不稳定性骨盆骨折在8种组合方法植入物的固定后均能得到明显改善,但采用ASA、AIA治疗前环损伤的生物力学总体性能要优于APA和AIA治疗的方法,PTP治疗后方损伤稳定性要优于SIJS固定。  相似文献   

9.
目的采用三维有限元方法对一种新型的棒-板内固定装置固定骶髂关节骨折脱位的力学性能进行分析,并与骶髂关节螺钉和前路植入钢板两种固定方法进行比较。方法根据CT扫描数据建立完整骨盆的三维有限元模型。去除模型一侧的骶髂关节韧带群模拟骨折脱位,然后使用棒-板内固定装置,骶髂关节螺钉和前路植入钢板进行模拟固定。对各模型施加同样的载荷来确定每种固定的力学性能。结果与骶髂关节螺钉和前路植入钢板相比,棒-板内固定装置可使骶髂关节的最大位移分别下降40%和42%。与对照组相比,棒-板内固定装置可使主要承载区的最大应力明显下降。此外,使用棒-板内固定装置固定可使髋部软骨和皮质骨的最大应力显著低于骶髂关节螺钉和前路植入钢板固定。结论由于棒-板内固定装置具有较好的力学性能,其可为骨盆骨折提供较稳定的固定方式。  相似文献   

10.
站、坐位态骨盆应力分布的实验研究   总被引:8,自引:0,他引:8  
目的:明确骨盆的应力分布,指导骨盆肿瘤瘤段骨切除后骨盆环的重建及人工半骨盆的设计与固定。方法:实验取完整骨盆的新鲜尸体(意外死亡)4具,采用应变计测量方法,对不同状态下骨盆的应力进行分析。结果:站立时,骶髂关节中部、耻骨支、髋关节前上方承受较大的压应变;而坐位时,坐骨支、骶髂关节中下部、耻骨支均承受较大的压应变。结论:站立时应力主要是经髋臼的前上方耻骨、骶髂关节传导,人工半骨盆置换设计与置换时,其结构应予加强,并作到确切固定,尤其是骶髂关节的中下部。  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.
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   

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.
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   

18.
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   

19.
Most bodily functions require the coordinated actions of complementary and supplementary paired muscle groups. Where this essential muscular cooperation is lacking, hollow organs may burst and others become literally screwed up, giving rise to many similar spastic diseases such as Torticollis, Twisted ovarian cyst, Torsion of the Testis, Volvulus of the intestines, Varicose Veins, Megacolon, Aortamegaly, Scoliosis, Erb's Palsy, Peyronie's Disease, Main-en-Griffe, Undescended Foot (Pes Cavus), Talipes, Strabismus. Spasm is “panenepidemic” and unclassified examples of Torsion Dystonia and Dyskinesia really are as common as debt and taxes.  相似文献   

20.
There is a sharp difference in how one views TCR structure–function–behaviour dependent on whether its recognition of major histocompatibility complex‐encoded restriction elements (R) is germline selected or somatically generated. The generally accepted or Standard model is built on the assumption that recognition of R is by the V regions of the αβ TCR, which is not driven by allele specificity, whereas the competing model posits that recognition of R is allele‐specific. The establishing of allele‐specific recognition of R by the TCR would rule out the Standard model and clear the road to a consideration of a competing construct, the Tritope model. Here, the case for allele‐specific recognition (germline selected) is detailed making it obvious that the Standard model is untenable.  相似文献   

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