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1.
86例86眼视网膜挫伤患者经过视觉眼电图检查。异常率81例(94%)。异常改变主要表现为光峰电位降低或者光峰电位和暗谷电位一致降低。患者Arden比有变化,部分降低,部分正常,部分增高。光峰电位降低幅度超过100Nu者63例(78%)。光峰电位降低幅度与视力变化受检时间和视网膜挫伤程度均无显著性差异。在诊断方面,EOG的价值与ERG和FFA作了对比。异常EOG和病理所见的视细胞损害相吻合。本文还对外伤性白内障、玻璃体积血和视神经挫伤的EOG检查进行了探索。  相似文献   

2.
目的:研究急性高眼压下视神经轴浆运输与视网膜光学功能之间的关系。方法:通过前房灌注的方法制造急性高眼压动物模型;利用罗兰电生理仪进行闪光视网膜电图和视觉诱发电位的测量。在玻璃体注射荧光染料后,利用激光共聚焦显微镜观察视神经轴浆运输,并利用苏木素-伊红染色,观察视乳头的形态变化。结果:当眼压为60 mm Hg并维持2 h,闪光视网膜电图的a波幅值明显降低,视网膜外层功能可能发生变化。当眼压为100 mm Hg并维持4 h,闪光视网膜电图的a波、b波和Ops的幅值以及闪光视觉诱发电位的幅值明显降低,视网膜内外层光学功能出现损伤,此时视神经的轴浆运输明显改变,视乳头形态也发生了变化。结论:急性高眼压下视神经轴浆运输与视网膜光学功能之间可能存在一定的关系。  相似文献   

3.
视觉功能修复方法   总被引:1,自引:0,他引:1  
视网膜修复的研究与应用,将帮助因视网膜病变导致失明的盲人重见光明.对当今视觉修复的主要方法,如药物疗法、玻璃体视网膜手术、器官克隆(治疗性克隆)、细胞培养(组织工程)和人工视觉等进行了介绍和比较.在这些解决方案中,人工视觉假体是当今最热门的研究课胚之一,对不同的视觉假体方案进行介绍和比较.最后介绍刺入式多电极阵列的视神经假体的研究新进展.  相似文献   

4.
现代科学研究表明至少有70%的外界信息是通过视觉系统被接受、分析和处理的。在视觉信息的处理和加工过程研究中占重要地位的是神经电活动。目前视觉电生理研究已拓展为神经生物学中取得长足进展的领域。视网膜是神经系统的外周感受器中了解得最清楚的区域之一;而对视皮层细胞结构和功能的研究远较大脑其它区域更为深入和清楚。随着视觉电生理的不断发展,越来越多的研究方法逐渐应用于眼科临床。如视觉诱发电位(Visual Evoked Potential,VEP)、视网膜电图(Electroretinograph,ERG)、眼电图(Electrooculargram,  相似文献   

5.
眼动脉及其分支的显微解剖学研究   总被引:2,自引:1,他引:2  
目的:研究眼动脉及其分支的显微解剖,为影像诊断、介入治疗和手术方案的制定提供解剖学依据。方法:肉眼及手术显微镜下观测30例(60侧)成人颅底湿性标本的眼动脉及其分支的形态、大小及毗邻关系。结果:①眼动脉分别起自颈内动脉床突上段起始部的前上壁(占93.34%)、海绵窦段前部(占3.33%)或脑膜中动脉(占3.33%),起始处外径为(1.46±0.40)mm。②眼动脉在视神经管内行于视神经下方、管底硬脑膜鞘内,在视神经管颅口处62.50%位于视神经内下方,在视神经管眶口处85.72%位于视神经外下方。③眼动脉眶内段分为3段,并形成2个弯曲。④视网膜中央动脉起始位置不恒定,起始处外径为(0.57±0.12)mm。结论:熟悉眼动脉的行径及其主要分支的正常解剖及变异,有利于眶尖区疾病的影像诊断和手术时避免损伤眼动脉及其分支。  相似文献   

6.
目的:研究视网膜电图(ERG)在视网膜缺血再灌注损伤过程中的变化,探讨其临床应用价值。方法:24只一侧眼视网膜缺血SD大鼠随机分成损伤组、预处理组及丹参组每组8只。损伤组:大鼠视网膜在缺血60min后,分别经再灌注30min、24~72h后测量ERG。预处理组:大鼠视网膜在缺血后60min前24h行5min短暂缺血,再经上述再灌注时程后测量ERG。丹参组:大鼠缺血60min前30min球后注射复方丹参注射液0.05ml,再经上述再灌注时程后测量ERG。结果:损伤组各时程b波下降明显(P〈0.001),预处理组及丹参组再灌注72h后b波恢复(P〉0.05)。结论:视网膜缺血再灌注损伤引起ERG的b波明显下降,ERG的b波是客观反映其损伤及功能恢复的敏感性指标。  相似文献   

7.
王君  杨立元  张艳  雷季良 《解剖学报》2009,40(4):551-554
目的 研究小鼠胚胎阶段Nogo-A在视网膜节细胞(RGCs)及其轴突上的表达及时程变化. 方法 取不同发育阶段的小鼠胚胎,采用免疫荧光染色,以激光扫描共焦显微镜观察Nogo-A在视觉传导通路中的表达.并采用免疫双标染色确定视网膜中表达Nogo-A蛋白的细胞类型. 结果 在视网膜发育的早期阶段(E12),Nogo-A密集表达于具有放射状形态的细胞上,Nogo-A免疫阳性产物出现在胞质、胞膜以及轴突上.Nogo-A与Tuj-1双标染色显示,此阶段的视网膜中几乎所有RGCs及其轴突都表达有Nogo-A;在稍晚的发育阶段(E13),视网膜中表达Nogo-A的RGCs数量明显减少,且仅出现在节细胞层以外的室周带和睫状体边缘区.在视网膜的神经纤维层,大部分RGCs轴突不再表达Nogo-A,仅有少量视觉纤维为Nogo-A免疫阳性;RGCs的神经发生基本完成后(E15), 视网膜中几乎检测不到Nogo-A免疫阳性的细胞,但视网膜纤维层仍有少量表达Nogo-A的节细胞轴突.与之类似,视神经盘、视茎、视交叉和视束都观察到少量Nogo-A免疫阳性的轴突.值得注意的是,视束中表达Nogo-A的纤维集中位于表浅部位,而此处恰为新近到达轴突的通过部位. 结论 Nogo-A在视网膜RGCs以及轴突上表达的时程变化和位置特点提示,新生RGCs及其轴突表达Nogo-A,成熟后RGCs内Nogo-A的表达则下调.推测新生RGCs及其轴突中表达的Nogo-A可能与减少轴突分叉等细胞的内在功能有关.  相似文献   

8.
目的:为视神经鞘减压术和视神经周围区手术提供视网膜中央动脉和睫状后动脉的解剖学资料。方法:采用显微解剖学技术对60例成人视网膜中央动脉和睫状后动脉进行观察。结果:(1)视网膜中央动脉多发自眼动脉角(21.7%),内侧睫状后动脉(20.0%),眼动脉第一段(19.3)。(2)视网膜中央动脉发起后在视神经下方弯曲前行,其起始部在眶内视神经后1/3段与眼外直肌之间者占85.0%。(3)入鞘点在视神经的正下方者68.3%,内下方者占21.7%,外下方者占10.0%。结论:视网膜中央动脉及睫状后动脉的起点、走行变化较大,视神经鞘减压术和视神经周围区手术时应保护好这些动脉,以免引起视神经等结构缺血。  相似文献   

9.
视觉诱发电位(visual evoked potential,VEP)为检测视神经上行通路皮质下结构(包括视神经、视交叉、视束、外侧膝状体和视放射)的神经电生理检查方法之一,主要反映视网膜视锥细胞的电活动情况,从而检测视觉通路神经的功能.Halliday等[1]最先将棋盘格翻转视觉诱发电位(PS-VEP)用于临床并获得肯定结果,其后VEP被广泛应用,已成为神经眼科学重要的辅助诊断手段之一.  相似文献   

10.
目的 研究进行性肌营养不良(Duchenne/Becker muscular dystrophy,DMD/BMD)患者视网膜眼电图(electroretinogram,ERG)表型与临床分型以及基因型的关系。进一步探讨不同基因型的DMD患者抗肌营养不良蛋白(dystrophin)及其同源蛋白在视网膜上的表面爱功能,揭示DMD出现ERG异常的分子机理,方法 用11对引物对22例临床确诊的DMD/BMD患者作三步多重PCR进行基因缺失分析,并行ERG检查,结果 DMD/BMD患者ERG改变与临床分型及病情严重程度无关,与DMD/BMD的基因型有关,基因中央区缺失型的ERG异常率明显高于基因非缺失型,结论 DMD/BMD的ERG改变与DMD基因突变位点有关,可能DP260转录启动子与视网膜电信号的传导关系最密切。  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.
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.
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   

19.
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   

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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