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81.
Zusammenfassung Es werden elektronenmikroskopische Beobachtungen zur Lokalisation und zur Feinstruktur der Glykolipideinschlüsse in verschiedenen inneren Organen bei Morbus Fabry berichtet. Die intrazellulÄren und extrazellulÄren Einschlüsse bestehen aus vielschichtig lamellÄren Membransystemen in konzentrischer und exzentrischer sowie in stapeiförmiger paralleler Anordnung. Diese lamellÄre Anordnung ist charakteristisch für flüssigkristalline Phasen von Phospholipid-Wasser-Systemen. Erstmalig werden ultrastrukturelle Befunde an den inneren Organen einer erkrankten Frau mitgeteilt. Demzufolge lassen sich bei heterozygoten Frauen gleiche Glykolipidablagerungen wie bei homozygoten MÄnnern nachweisen. Die Beziehung der Glykolipideinschlüsse zu den Lysosomen wird erörtert.
Electron microscopic observations in internal organs in morbus fabry
Summary Electron microscopic findings are reported on the localization and fine structure of glycolipid inclusions in different organs (heart, kidney, lymph nodes, arterial blood vessels, pancreas) in Fabry's disease in a female. The intracellular and extracellular inclusions were made up of multilamellar membraneous systems in concentric, excentric, and parallel arrangement. This fine structure is characteristic of liquid-crystalline phases of phospholipid-water systems.The same type of inclusions are found in the internal organs of heterozygotic women as in homozygotic men. The relationship between the glycolipid inclusions and the lysosomes is discussed.
Herrn Prof. Dr. F. Bolck, Direktor des Pathologischen Instituts der Friedrich-Schiller-UniversitÄt Jena, zum 60. Geburtstag gewidmet.  相似文献   
82.
Summary Light bodies are large cytoplasmic granules originally described in the gonadotrophic cells of the rat pituitary gland. In order to determine whether similar bodies occur in the human anterior pituitary gland, 89 pituitary adenomas and periadenomatous tissue from 20 cases were examined by transmission electron microscopy. Double membrane bound bodies with filamentous internal structure identical to rodent light bodies were identified in 10 hormone-producing adenomas: 5 PRL, 1 PRL-GH, 2 GH, and 2 ACTH-producing tumours. No light bodies were found in the remaining 79 tumours nor in the pituitary cells in periadenomatous tissue from 20 cases. These results show that some human pituitary adenomas may contain light bodies identical to those seen in gonadotrophs of rat pituitary.Abbreviations PRL prolactin - GH growth hormone - ACTH adenocorticotropic hormone - FSH follicle-stimulating hormone - LH luteinizing hormone  相似文献   
83.
目的 :观察人球结膜微血管的超微结构 ,认识白内障时球结膜微血管的电镜改变 ,为微循环和眼科研究工作提供参考。方法 :观察对象为 5例老年性白内障、1例糖尿病性白内障 ,术前一般状态良好。在白内障手术时取球结膜标本。电镜常规固定、包埋、定位、超薄切片、用电镜观察。结果 :球结膜毛细血管多由 2~ 3个内皮细胞围绕而成。核多为长椭圆形 ,核周缘有轻度凸凹。近腔侧胞浆细胞器较多 ,微丝和微管十分发达。基底膜、周细胞与一般毛细血管相似。 6例白内障球结膜毛细血管的内皮细胞、基底膜、周细胞、管腔都有不同程度的变化。其电镜改变可以分为三类 :( 1)代偿反应性增强改变 :微丝、微管十分发达、核周深凹、胞体突入管腔内、内皮细胞突起穿越基底膜、白细胞穿壁 ;( 2 )可恢复性退变 :线粒体退变、核质周集、胞浆出现空泡、基底膜分层、弥散、小量出血 ;( 3)严重不可恢复性改变 :核质固缩、腔内红细胞融合、血红蛋白溢出弥散、管壁断裂、腔内充满退变、裂解结构 ( 2例 ) ,并通过断裂处出至基底膜外。结论 :白内障病人球结膜微血管的超微结构有程度不等的改变  相似文献   
84.
本研究用扫描电镜、透射电镜和光镜,观察了早期鸡胚心脏发生的外形变化及心外膜的发生。1.心脏发生经历2个阶段,首先是心脏的成襻过程,心管表面的一定部位出现沟,沟相应部位内面出现嵴。心襻的完成,标志着心脏各部原基的确立。第2个阶段是心脏各部原基的进一步分化,包括心腔内部的分隔及心脏各部位置的变化。心房与心锥的移位,可能是受左右心室移位的影响。2.心外膜片并非由心肌外层原位分化,而是由静脉窦处的间充质细胞增殖,并迁移覆盖在心肌层表面形成。  相似文献   
85.
Wheat streak mosaic virus is a Tritimovirus, a member of the Potyviridae family, which includes the very large Potyvirus genus. We have examined wheat streak mosaic virus by electron microscopy and fiber diffraction from partially oriented sols, and analyzed the results to estimate the symmetry and structural parameters of the viral helix. The virions have an apparent radius of 63 +/- 5 A. The viral helix has a pitch of 33.4 A +/- 0.6 A. There appear to be 6.9 subunits per turn of the helix, although we cannot completely eliminate values of 5.9 or 7.9 for this parameter.  相似文献   
86.
 The organization of the cytoskeleton has been studied during mouse differentiation in cells of the myenteric neuronal lineage. The entire gut was examined starting from day 12.5 of embryonic life (E12.5) until birth (P0). Immunocytochemistry was performed to evaluate the expression of five of the most represented neurofilaments proteins (the low, NF-L, medium, NF-M, and heavy, NF-H, molecular weight subunits, α-internexin and peripherin) and of two of the microtubule-associated proteins (MAP1 and MAP2a+2b). In parallel, the appearance in the differentiating myenteric neurons of filamentous and microtubular structures and their intracytoplasmatic distribution were observed under the electron microscope. A differential immunohistochemical expression of the structural proteins was found. Immature cells expressed α-internexin, peripherin, NF-M and MAP1 by day E12.5; α-internexin expression was strong in these cells, but gradually decreased with age and was practically absent in adulthood. Conversely, the expression of the other three proteins increased with cell differentiation and was still present in adulthood. NF-L and NF-H expression appeared later, by day E16.5, and was weak for the entire pre- and postnatal life. MAP2a+2b was never expressed. Under the electron microscope, at day E12.5 the cytoskeleton was already organized in filamentous and microtubular structures. At this age neurofilaments were few and mainly located in the cell processes, and microtubules were numerous and mainly assembled in the neuritic growth cones, together with synaptic vesicles. With ageing, neurofilaments and microtubules were ubiquitous in the neuron. Data obtained demonstrate that cytoskeletal proteins gradually accumulate in the cells of the neuronal lineage in parallel with the organization of the cytoskeletal structures, which in turn mediate important neural events by the earliest stages of murine embryonic life, including growth of nerve processes and initiation of axonal transport. Accepted: 11 November 1998  相似文献   
87.
本实验用大鼠主动脉结扎的心肌肥大模型,结合电镜酶细胞化学技术,观察心肌肥大发展过程中溶酶体的变化。结果表明:心肌肥大发展时,溶酶体参与心肌细胞改建;到心肌肥大后期,出现大量自噬现象,造成心肌不可逆损伤。  相似文献   
88.
党小荣  张文斌 《神经解剖学杂志》2002,18(2):173-177,T036
应用四甲基罗达明逆行标记和免疫荧光技术相结合 ,在激光扫描共聚焦显微镜下对大鼠孤束核内 5 -HT能纤维和终末与向臂旁核投射的 NOS阳性神经元之间的联系进行了观察。将四甲基罗达明注入一侧外侧臂旁核后可见孤束核尾段背内侧、胶质、小细胞、内侧、中间内侧等亚核和连合亚核内出现较多的逆标神经元 ,四甲基罗达明逆标和 NOS阳性神经元以及 5 -HT阳性终末重叠分布 ,其中四甲基罗达明和 NOS双重阳性神经元分别占四甲基罗达明逆标和 NOS阳性神经元总数的 8.3% ( 14 /16 8)和 18.4% ( 14 /76 )。在此 5 -HT样阳性纤维和终末包绕着 NOS阳性神经元、四甲基罗达明逆标神经元及四甲基罗达明和一氧化氮合酶双重阳性神经元的胞体和树突 ,形成点状紧密接触。本研究结果提示 ,孤束核内来自下行性抑制系统的 5 -HT能纤维和终末可能与向臂旁核投射的 NOS阳性神经元形成突触联系 ,从而可对 NOS阳性神经元所传递的包括伤害性信息在内的内脏感觉传入信息发挥抑制性调控作用  相似文献   
89.
Summary In order to clarify the histogenesis of clear cell sarcoma of tendons and aponeuroses (CCS), two cases of human and one nude mouse-transplanted CCS line were studied using an ultrastructural and enzyme cytochemical approach. Most of the tumour cells obtained from the primary and transplanted CCS demonstrated melanosomes in various stages of development within the cytoplasm, whereas no melanosomes could be identified in the metastatic CCS. However, cholinesterase and tyrosinase activities could be demonstrated not only in the melanotic primary and transplanted CCS but also in the amelanotic metastatic CCS. The results therefore support the hypothesis that CCS is a soft tissue tumour derived from the neural crest.  相似文献   
90.
Summary Morphologic studies of pituitary neoplasms removed by surgery from 36 human patients revealed 8 chromophobe adenomas which differed clearly from the remaining tumors. The cytoplasm of the adenoma cells failed to stain with PAS, aniline blue, aldehyde fuchsin, aldehyde thionin, orange G or light green, but positively stained granules were found by using erythrosine or carmoisine. Immunoperoxidase technique disclosed the presence of prolactin in the cytoplasm of some adenoma cells. The adenoma cells exhibited distinct ultrastructural features such as well developed rough surfaced endoplasmic reticulum with Nebenkern formation, prominence of Golgi apparatus, presence of misplaced exocytosis as well as pleomorphism of secretory granules with a considerable variation of size ranging from 130 to 500 nm in diameter. Thus, by electron microscopy the adenoma cells showed a close resemblance to prolactin cells of the non-tumorous pituitary glands except for the reduced size and number of secretory granules.These chromophobe adenomas are regarded as representing a distinct pathological entity clearly distinguishable from other forms of pituitary neoplasms. In view of the morphologic findings and the elevation of blood prolactin level (measured in 3 patients) the term, sparsely granulated prolactin producing pituitary adenoma, appears to be the most appropriate one to designate these tumors.The authors wish to thank Dr. H. Friesen for providing the anti-human prolactin and Dr. L. A. Sternberger for the peroxidase-anti-peroxidase complex. The excellent technical assistance of Mrs. Gezina Ilse and Miss Nancy Macphail and the valuable secretarial help of Mrs. Maureen Rowling are appreciated.The work was supported in part by MA-552 grant of the Medical Research Council of Canada and by the St. Michael's Hospital Research Society.  相似文献   
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