天疱疮皮肤的电子显微镜观察

天疱疮系一种较罕见的皮肤病,目前多认为属自体免疫性疾病。迄今尚未见到有关这种病的电镜观察材料。本文介绍对天疱疮损害处皮肤的电镜观察结果。病历摘要:患者男性,38岁。临床皮检及病理组织学均诊断为寻常性天疱疮。血清检查IgG45.30mg/ml,IgA3.32mg/ml,IgM1mg/ml。一、表皮棘层超微病变的电镜观察在表皮之基底层上方发生棘层松解,未见炎细胞浸润。在早期损害处不但相邻棘细胞之间(非桥粒区)的间隙开始增宽,而且桥粒区棘细胞之间的间隙也明显增宽,宽达50nm(正常为20nm),间隙中粘合物质的密度减低、     

中枢神经细胞瘤的超微结构观察

应用光镜检查及免疫标记,对2例中枢神经细胞瘤进行电镜观察.结果显示,中枢神经细胞瘤在电镜下具有一定的结构特征：瘤细胞间可查见桥粒样结构;胞质内有神经分泌颗粒和哑铃状致密核心颗粒;胞突内有丰富的微管和囊泡状结构.在外科病理诊断中,中枢神经细胞瘤难以与少突胶质细胞瘤、透明细胞室管膜瘤等肿瘤鉴别.电镜检查对鉴别诊断有比较重要的意义.肿瘤细胞胞突内的微管和囊泡、胞质内的神经内分泌颗粒等超微结构与免疫组织化学标记一致,同时也提示肿瘤起源于神经元细胞.     

盖玻片在培养细胞免疫电子显微术中的应用

体外培养的细胞不仅可用于研究其形态和机能的变化,而且可进行不同药物学作用时细胞内抗原成分的定位检测及细胞特征的研究。通常盖玻片放入培养皿中作为培养细胞的支持物,细胞在盖玻片上长成单层,可立即固定、染色,进行光学显微镜的观察。在实验中我们发现,加盖玻片的单层细胞培养法也可以直接应用于免疫电镜的包埋前和包埋后染色方法。该技术具有以下优点。(1)使用盖玻片可以避免免疫电镜标本制作过程中,为了搜集细胞而进行的数次刮取、离心。免疫反应及后固定、脱水、浸透、包埋均在盖玻片上进行,使培养细胞的损伤降低至最小程度。(2)如果在直径3．5cm的培养皿中进行免疫过氧化物酶反应大约需要至少200μl抗体,而使用盖玻片法,每张盖玻片则仅需要10μl抗体,大大节约了免疫反应的抗体量,既简便又经济。(3)盖玻片法使包埋后培养细胞呈单层位于包埋块的表面,在每一张超薄切片中都能观察到很多细胞。     

免疫胶体金标记电镜技术在研究埃希氏大肠杆菌987P粘着素抗原结构上的应用

作者以单克隆抗体为第一抗体,应用免疫胶体金标记电镜技术研究了埃希氏大肠杆菌987P粘着素抗原结构。结果表明,该粘着素由相同的亚单位组成,并呈螺旋状结构。每个亚单位包含着几个相同的抗原决定簇分子,与酶联免疫吸附电镜技术相比较,该法除具有单克隆抗体极高特异性的特点外,还其有大小一致的胶体金颗粒致密附着在抗原相关位点上,清晰易于识别的优点。     

免疫金法与ABC法在电镜包埋前染色之比较

包埋后免疫电镜术虽能精确定位抗原,但难度大。本文用胶体金标记法与ABC法对人鼻中线恶网瘤组织在树脂包埋前作抗人T细胞免疫染色,并对两种方法进行比较。简述如下:临床活检鼻中线恶网组织,经4％多聚甲醛加1％戊二醛4℃固定,振动切片(50μm),PBS冲洗,在预先硅化的载玻片上作免疫染色:鼠抗人T细胞McAb(Dako公司出品)孵育过夜;金标羊抗鼠抗体(10nm,军科院基础所出品)室温下孵育1小时,再将切片倾入小瓶,经1％锇酸后固定,常规脱水包埋及超薄切片,不作铀铅复     

单克隆免疫球蛋白轻链相关性肾病的超微结构及免疫电镜研究

目的：探讨电镜及免疫电镜方法在单克隆免疫球蛋白轻链相关性肾病包括轻链沉积病(Light chain deposition disease,LCDD)和轻链型淀粉样变(amyloidosis,AL)诊断中的作用。方法：对我院1994．1～2002．12间接受的肾活检病例进行系统的电镜观察,对疑为LCDD及早期AL的病例进行轻链(κ、λ)的免疫电镜标记。结果：7例符合LCDD的诊断,45例符合AL的诊断。LCDD肾活检组织电镜下可见肾小管基底膜(TBM)外侧、肾小球基底膜(GBM)内侧、鲍曼囊外侧及小血管壁基底膜外侧的点状、颗粒状电子致密物质沉积,其中2例早期病例表现颗粒状物质节段性分布;免疫电镜标记,颗粒状物质被单种轻链标记,其中,κ轻链5例,λ轻链2例。AL肾活检组织电镜下可见肾小球系膜区、GBM及小动脉壁基底膜上的细纤维物质呈团片状或束状分布,其中15例早期病例表现系膜区或,及GBM的细纤维呈节段性分布;15例早期AL的免疫电镜标记结果,细纤维被单种轻链标记,其中,κ轻链4例,λ轻链11例。结论：肾脏LCDD及早期AL的诊断需依赖于电镜检查,免疫电镜检查对肾脏早期LCDD及早期AL的确诊具有不可替代的作用。     

中毒所致肝细胞中间丝及其抗原决定簇的改变

应用电镜及免疫电镜技术我们观察了CCl_4中毒引起的肝细胞中间丝(IF)及其抗原决定簇的改变。结果表明,中毒10天后,IF构成的毛细胆管鞘(PCS)增粗,壁增厚,IF表面突起增多,细胞角蛋白(CK)19阳性金颗粒首先出现于IF突起及分支处,与CK18阳性金颗粒可位于同一段IF,甚至同一突起上;至中毒第40和第50天(肝硬变期),某些肝细胞胞浆内遍布密集的IF,与胆管上皮相似,CK19阳性IF比例显著增加,而且CK19阳性金颗粒可见于许多IF主干上。这提示,CCl_4性肝炎及肝硬变中,某些肝细胞在IF结构及CK组型上都发生了向“胆管型”的转变。     

A型口蹄疫病毒与中和性抗体的复合物结构解析

口蹄疫病毒(foot-and-mouth disease virus, FMDV)是感染猪、牛、羊等偶蹄动物的烈性病原，严重危害畜牧业的发展以及相关产品的对外贸易。FMDV包含七个血清型，其中A型FMDV抗原结构变异最大，因此解析A型FMDV保守抗原结构对广谱疫苗分子设计具有重要指导意义。据此，本文作者利用冷冻电镜技术解析了A型FMDV与中和性抗体P22C复合物的三维结构。发现P22C结合于A型FMDV颗粒的三重轴附近，接触面多数氨基酸位于衣壳蛋白VP2 B-C环，其次是E-F/H-I环以及VP3 B-B “结节”上不连续的少量氨基酸。其中，VP2的72、77与195位氨基酸通过氢键与抗体相互作用，可能是影响结合的关键位点。进一步的结合自由能分析支持该猜测，提示72位点是组成抗原表位的关键决定簇，而H77W和S195L突变则可进一步降低结合自由能从而提高与抗体的亲和力。结合自由能分析也说明了P22C具有较高的成熟度。研究结果揭示了A型FMDV的抗原结构信息，为FMDV疫苗分子设计提供了一个重要靶点。     

嗜酸性粒细胞的异常颗粒

嗜酸粒细胞颗粒分两种:A型颗粒,基质中含有结晶;B型颗粒较小,内容物均匀。颗粒表面都有一层膜。颗粒内含多种酶,能向吞噬体内或细胞外释放。本文将报导嗜酸粒细胞中一种极少见的非A非B型颗粒。此种异常颗粒园大无晶体,基质不均匀和高度不透明。一、材料和方法:胸水,取自一肺腺癌患者。经远心分离将细胞用戊二醛和四氧化锇双固定丙酮系列脱水,“812”树脂包埋,60C聚合,LKB机切片,醋酸铀和柠檬酸铅复染。用D×A4—10型国产电镜观察。二、结果:本病例的嗜酸粒细胞,都有许多异常的大颗粒,直径约1.5—2.0μ。通常排列在细胞边缘,个别出     

硅基锗光接收器在近红外显示高响应度

锗(Ｇｅ)可与具有硅(Ｓｉ)基装置的发射器、调制器和探测器集成,因此锗光接收器在光通信中有价值。麻省理工学院和罗马Ｔｅｒｚａ大学的研究人员建造了异质结连接硅基锗光接收器,在正入射下显示近红外已知的最高灵敏度。研究人员在900°Ｃ退火的ｐ型Ｓｉ基晶片上生长1μｍ厚的Ｇｅ层。在132μｍ和155μｍ分别测得055Ａ/Ｗ和025Ａ/Ｗ的灵敏度,优于ＳｉＧｅ基多量子阱的导波器件。在1Ｖ电压时,该器件有30ｍＡ/ｃｍ2相对大的反向偏置电流密度,归因于ｐ型Ｓｉ和本征Ｇｅ间异质结处的低势垒。使用ｐｉｎ结构应该能降低此密度硅基锗光接收器在近红…     

Comparison of the thickness of basement membranes in various tissues of the rat

The thicknesses of the lamina lucida and the lamina densa of basement membranes in various kinds of tissues, including the epidermis and mucosal epithelium, and basement membranes adjacent to a Schwann cell, perineurial sheath cell, endothelial cell, pericyte, muscle cell and fat cell, were compared on high-powered transmission electron micrographs. Each tissue and cell possessed a basement membrane with thicknesses of the lamina lucida and lamina densa that were specific to the particular tissue or cell. This indicates that the lamina lucida and lamina densa of the basement membrane of a tissue/cell have a particular constitution. New theories on the molecular constitution between the cell surface and basement membrane may need to be developed.     

Electron microscopic observation of 137Cs-irradiated rat testis: production of basal laminae for germ cells, despite their absence

Whole body gamma-ray irradiation of rats with caesium-137 (137Cs) at embryonic day 20 induced marked reduction of the weight of the testis. Body weight and other tissues, however, seemed to remain normal. By light microscopy, complete loss of germ cells was observed in the testis. Other components, such as Sertoli cells and interstitial cells, seemed to be normal. The testes from day 8 postpartum rats contained very few spermatogonia compared with newborn rats, indicating loss of germ cells between days 0 and 8. In the adult, 137Cs-irradiated testes showed two conspicuous features other than the loss of germ cells: empty vacuolar spaces between Sertoli cells and multilayered seminiferous tubule basal laminae (lamina densa). The junctional structures (ectoplasmic specializations) between Sertoli cells, however, seemed normal. The thickness of each layer of multilayered basal laminae was the same as that of normal rats and electron-lucent layers similar to lamina lucida were interposed between them. Of the empty vacuolar spaces between Sertoli cells, basal laminae bridge the gap. The basal laminae contained laminin, type IV collagen and heparan sulphate proteoglycan evenly distributed among layers, suggesting a normal composition. Rough estimation of the amount of basal laminae deposited in 137Cs-irradiated rats indicates that it is within a range similar to that in normal testis. These features imply that Sertoli cells are, in part, determined perinatally to produce basal laminae for germ-line cells.     

Aiport综合超微病理诊断及鉴别诊断

对3284例肾活检中20例(0．6％)Alport综合征(AS)进行回顾性总结。20例AS中男性12例(60％),女性8例(40％);成人15例(75％),儿童5例(25％)。AS电镜下以肾小球毛细血管基底膜(GBM)病变为主,8例(40％)表现为GBM增厚．致密层纵行撕裂形成板层状或编篮状,12例(60％)表现为GBM弥漫变薄和厚薄不均。9例(45％)肾间质中有泡沫细胞浸润。结论：并非所有AS具有典型的GBM增厚,分层或编篮状改变;部分病例GBM分层并不明显;肾间质中泡沫细胞浸润对AS有重要提示作用。本文结合文献对AS的诊断及鉴别诊断进行了探讨。     

A general framework for reversible data hiding in encrypted images by reserving room before encryption

In this paper a general framework to adopt different predictors for reversible data hiding in the encrypted image is presented. Employing linear regression, we propose innovative predictors that contribute more significantly to accomplish more payload than conventional ones. Reserving room before encryption (RRBE) is designated in the proposed scheme making possible to attain high embedding capacity. In RRBE procedure, pre-processing is allowed before image encryption. In our scheme, pre-processing comprises of three main steps: computing prediction-errors, blocking and labeling of the errors. By blocking, we obviate the need for lossless compression to when a content owner is not enthusiastic. Lossless compression is employed in recent state of the art schemes to improve payload. We surpass the prior arts exploiting proper predictors, more efficient labeling procedure and blocking of the prediction-errors.     

Sentence segmentation for classical Chinese based on LSTM with radical embedding

A low-than character feature embedding called radical embedding is proposed,and applied on a long-short term memory(LSTM) model for sentence segmentation of pre-modern Chinese texts.The dataset includes over 150 classical Chinese books from 3 different dynasties and contains different literary styles.LSTM-conditional random fields(LSTM-CRF) model is a state-of-the-art method for the sequence labeling problem.This model adds a component of radical embedding,which leads to improved performances.Experimental results based on the aforementioned Chinese books demonstrate better accuracy than earlier methods on sentence segmentation,especial in Tang’s epitaph texts(achieving an F1-score of 81.34%).     

Manifold learning for face recognition under changing illumination

Appearance-based methods have been proven to be useful for face recognition tasks. The main problem with appearance-based methods originates from the multimodality of face images. It is known that images of different people in the original data space are more closely located to each other than those of the same person under different imaging conditions. In this paper, we propose a novel approach based on the nonlinear manifold embedding to define a linear subspace for illumination variations. This embedding based framework utilizes an optimization scheme to calculate the bases of the subspace. Since the optimization problem does not rely on the physical properties of the factor, the framework can also be used for other types of factors such as pose and expression. We obtained some promising recognition results under changing illumination conditions. Our error rates are comparable with state of art methods.     

Location of peptidoglycan and teichoic acid on the cell wall surface of Staphylococcus aureus as determined by immunoelectron microscopy.

Anti-peptidoglycan (PG) and anti-teichoic acid (TA) antibodies were prepared from sera of rabbits immunized with the cell wall fraction of Staphylococcus aureus Cowan I by the specific adsorption technique with purified teichoic acid or peptidoglycan. The anti-PG antibody recognized the trichloroacetic acid-treated walls (TCA wall) prepared from S. aureus, Bacillus subtilis, and Micrococcus luteus but did not react with teichoic acid or proteins extracted from the cell wall of Staphylococcus. The anti-TA antibody specifically reacted with cell wall teichoic acid of beta-type sugar configuration. The reaction sites of these antibodies on the cell wall of S. aureus Wood 46 were determined by immunoelectron microscopy using colloidal gold as a probe. The anti-TA antibody reacted mostly with the fibrous electron-dense mass on the cell surface. The reaction was also seen on the inner surface of the cell wall. The anti-PG antibody reacted with the fibrous structures and also directly on the cell wall surface. The distribution of the probes on the cell wall surface examined with the scanning electron microscope showed that there was no localized distribution in respect to the cell division. We knew from these observations that the external surface of the cell wall of Staphylococcus is covered with the fibrous mass which consists mostly of teichoic acid but partially of peptidoglycan.     

基于比特控制的快速矩阵嵌入

为了保证安全和信息传输率,隐写术期望能利用对载体的每个修改嵌入尽可能多的信息,也即提高嵌入效率。矩阵嵌入是最主要的提高嵌入效率的编码方法。Fridrich提出的基于随机线性码的矩阵嵌入方法能达到高的嵌入效率,但是计算复杂度较高。该文利用择多校验法对矩阵嵌入进行改进,首先使用控制比特对载体分组进行异或构造新载体,然后在新载体上执行矩阵嵌入,通过考察控制比特的状态可以快速生成修改量尽可能小的模式。分析和实验表明,该方法可以在嵌入效率和嵌入速度之间灵活的进行折中。与Fridrich的原始方法相比,新方法在保持嵌入效率基本不变的情况下,其计算复杂度随着控制比特数的增加以指数速度降低。与已有的快速矩阵嵌入方法比,新方法能以更快的嵌入速度达到更高的嵌入效率。     

纤维联接蛋白FN、凝血酶敏感蛋白(TSP)在成纤维细胞及骨髓基质细胞的免疫电镜定位

本文用免疫电镜技术(过氧化酶标记和胶体金标记)在来自兔角膜瘢痕的纤维母细胞和来自小鼠骨髓的长期培养的基质上进行了纤维粘连蛋白(FN),血小板凝血酶敏感蛋白(TSP)定位。结果显示在纤维母细胞和骨髓基质细胞表面以及细胞外细纤维构成的网中。另外,有时在上述二种细胞胞浆中也可以看到FN和TSP的定位。应用免疫电镜技术可以研究各种结缔组织增生性疾病,FN和TSP的分布以及它们和结缔组织增生的关系,为纤维化形成机制以及胶原形成细胞、基质细胞和其它细胞的关系提供了形态学依据。     

新型肺癌压电DNA传感器的研制

在压电石英金电极上自组装半胱胺膜,通过1-乙基-3-(3-甲基氨丙基)碳二亚胺盐酸盐和N-羟基琥珀酰亚胺活化的羧基化碳纳米管交联半胱胺和DNA探针,构建新的压电DNA传感器,实现对肺癌特征DNA的压电检测。该传感器检测灵敏度为27.617Hz/(μg/mL),线性范围为0.02～7.50μg/mL,再生性能好。样本分析结果与聚合酶链式反应(PCR)法无显著差异,可用于临床检测。