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31.
E. A. Érenpreisa R. A. Zirne N. D. Zaleskaya T. G. Sjakste 《Bulletin of experimental biology and medicine》1988,106(5):1605-1608
Laboratory of Chemistry of the Cancer Cell, Latvian Research Institute of Experimental and Clinical Medicine, Ministry of Health of the Latvian SSR, Riga. (Presented by Academician of the Academy of Medical Sciences of the USSR I. B. Zbarskii.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 106, No. 11, pp. 591–593, November, 1988. 相似文献
32.
Nerve biopsy findings in Niemann-Pick type II (NPC) 总被引:1,自引:0,他引:1
A. F. Hahn J. J. Gilbert C. Kwarciak J. Gillett C. F. Bolton C. A. Rupar J. W. Callahan 《Acta neuropathologica》1994,87(2):149-154
The severe infantile form of Niemann-Pick disease type II was diagnosed in a 4-year-old girl and confirmed by demonstrating in cultured skin fibroblasts a deficiency of low-density lipoprotein-stimulated cholesterol ester synthesis of < 5% of normal. Electrodiagnostic studies revealed changes of a predominantly demyelinating motor and sensory polyneuropathy. Light microscope and ultrastructural examination of a peroneal nerve biopsy showed unique changes. Compacted myelin sheaths were disproportionately thin with marked globular irregularities in single teased nerve fibres and evidence of chronic demyelination. The majority of axons were preserved but axonal spheroids and cytoskeletal abnormalities akin to neuroaxonal dystrophy were noted. Membrane-bound multilobulated lysosomal inclusions of floccular and electron-dense material were present in Schwann cells (SC), endoneurial fibroblasts, macrophages, pericytes and endothelial cells. SC of myelinated fibres were stuffed with whorls of concentric osmiophilic membranous profiles and electron-lucent material. The findings are diagnostic and differ from those of classical Niemann-Pick disease. 相似文献
33.
Summary Ultrastructural and tracer studies have demonstrated that vasogenic edema, a serious complication of brain tumor is the result of increased permeability of tumor vessels. However, not much information is available on the alterations in the vessels in the peritumoral areas. Therefore, we studied the ultrastructural changes in the tumor micro-blood vessels (MBVs) in 20 cases of glioma and compared these with the changes in the peritumoral MBVs in 10 of these cases.The tumor MBVs showed remarkable structural changes, viz, increase in pinocytotic vesicles, large vacuoles and microvilli in the endothelial cells, varying degrees of endothelial attenuation and fenestration, an occasional partially or completely opened-up junction and some pale and edematous endothelial cells, which can adequately explain their increased permeability.The peritumoral MBVs also showed evidence of increased permeability in the form of increased pinocytotic vesicles, large vacuoles and microvilli associated with pale and edematous cytoplasm of some endothelial cells. Thickened multilayered basement membrane, absence of ensheathment of capillary basement membrane by astrocytic cell processes and widened perivascular space were observed in both tumoral and peritumoral MBVs.An interesting observation was that in the peritumoral MBVs, the pinocytotic vesicles were most conspicuously seen on the abluminal side of the endothelial cells often fused with the abluminal plasma membrane. Although a static study like this cannot indicate any definite direction of movement of fluid, we feel that the occurrence of reverse pinocytosis is a distinct possibility in the peritumoral MBVs and that it may be an important means of resorption of edema fluid. 相似文献
34.
患实验性牙龈炎的大鼠牙龈(6例)经脉冲掺钕钇铝柘榴石激光(Nd:YAG激光)照射后进行光镜及超微结构观察。目的在于了解低能量Nd:YAG激光照射对牙龈炎症的治疗作用。炎症牙龈经输出能量为1.5W,脉冲数为20PPS的激光照射后与对照组相比较,形态学上有如下变化:上皮细胞无变性;牙龈上皮层数较炎症时减少;上皮下炎细胞浸润明显减少;上皮细胞间隙变小;上皮下结缔组织内产生大量的排列致密的胶原纤维。结果提 相似文献
35.
酒精染毒后大鼠睾丸生精小管超微结构的改变 总被引:3,自引:0,他引:3
目的:观察酒精染毒后大鼠睾丸生精小管超微结构的变化。方法:将48只W istar雄性性成熟健康大鼠随机分为对照组(A组)、染毒组(B组),每组24只,B组用50度酒精(6 m l/kg)每天灌胃染毒1次,连续39 d,A组用生理盐水灌胃(6 m l/kg);在第14、27、40 d分别从A、B两组中各处死8只大鼠,取睾丸组织,常规电镜制片,透射电镜观察大鼠睾丸生精小管超微结构。结果:透射电镜发现:对照组各时间段睾丸生精小管超微结构无明显变化,基膜平滑、致密、厚薄均匀,支持细胞胞质丰富、粗面内织网及线粒体较多,核大、核质均匀、核仁清楚,精原细胞与基膜和支持细胞之间连接紧密,紧密连接层次清楚。染毒组第1生精周期末(相当于第14 d)超微结构开始变化;第2、3个生精周期末(分别相当于第27、40 d)超微结构变化最明显,主要表现为:①支持细胞溶酶体增多,线粒体肿胀空泡化,细胞器模糊且数量减少,支持细胞内出现较大空泡,甚至支持细胞出现萎缩;②精原细胞与支持细胞及生精小管的基膜之间出现较多较大空泡;③精原细胞凋亡,凋亡小体边集;④生精小管内的精子有过多的胞质且有大小不一的空泡,尾部断面线粒体排列不整齐、缺失或堆积;⑤紧密连接层次改变、模糊不清;⑥基膜厚薄不均,基膜外胶原组织疏松增厚,成波浪式皱褶,可见基膜断裂。结论:酒精可引起大鼠睾丸生精小管的基膜、紧密连接、支持细胞等超微结构异常,并可引起精原细胞凋亡。 相似文献
36.
带宫内避孕环系常用之节育措施,不正常子宫出血系常见之并发症。本文旨在研究发生出血的机制,提出改进意见,以利于带环妇女的健康,提高带环率。本文对12例带不锈钢环后月经过多妇女的子宫内膜进行超微结构研究,与6例带环而月经正常的妇女对比,结合基础体温、血雌孕激素测定等资料加以讨论。研究结果表明:(1)带环不影响卵巢功能。(2)环周围区与远离区内膜发育的不同步可能是出血过多的重要原因。(3)选择大小适宜的环(宁小勿大)既提高避孕效果又避免出血过多。 相似文献
37.
38.
A 68‐year‐old man, who had no remarkable past medical history, was referred to a hospital because of disorientation and right‐sided hemiparesis. On magnetic resonance imaging, a contrast‐enhanced tumor in the left frontal lobe with perifocal edema was noted. He underwent left frontal lobectomy. Microscopic examination revealed infiltrative atypical astrocytes showing increased cellularity, distinct nuclear atypia, and many mitotic figures, while microvascular proliferation and necrosis were absent. Thus, the tumor was histologically diagnosed as anaplastic astrocytoma. It was of note that cytoplasmic eosinophilic granules were observed in approximately 25% of neoplastic cells. The granules were positively immunostained with anti‐αB‐crystallin antibody, and the other histochemical and immunohistochemical results also corresponded to Rosenthal fibers. The MIB‐1 labeling index of the highest area of the tumor was 22%, while that of granular cells was 2.1%. An ultrastructural study revealed amorphous electron‐dense structures attached to intermediate filament bundles, compatible with Rosenthal fibers. Such structures are relatively common in oligodendroglial tumors; however, they are extremely rare in astrocytic tumors. Fluorescence in situ hybridization targeted against chromosome 1 failed to demonstrate allelic loss of the short arm. The present case should also be discriminated from granular cell astrocytoma. We review related literature and discuss the significance of granules in gliomas. 相似文献
39.
枸杞多糖对氧化损伤大鼠晶状体上皮细胞凋亡的调控 总被引:5,自引:1,他引:4
目的 :研究枸杞多糖 (lyciumbarbarumpolysaccha rides,LBP)对实验性晶状体氧化损伤所致晶状体上皮细胞(lensepithelialcell,LEC)凋亡的影响。方法 :复制大鼠晶状体LEC凋亡模型 ,将 2 4只透明晶状体随机分为 4组 ,空白组、H2 O2 组、白内停组、枸杞多糖组。枸杞多糖组加入终浓度为1g/L的枸杞多糖共同孵育 2 4h ,采用TUNEL法检测LEC凋亡率 ,用透射电子显微镜观察LEC超微结构改变。结果H2 O2 组LEC凋亡率 (92 .0± 2 .5 5 )显著高于空白组 (3.5± 1.84 ) ,(t=6 2 .97,P <0 .0 1) ;枸杞多糖组LEC凋亡率 (16 .6±8.11)与白内停组比较 ,差异有非常显著性 (t=15 .5 0 ,P <0 .0 1)。透射电镜观察 ,H2 O2 组胞浆明显浓缩 ,核内染色质凝聚或成块 ,枸杞多糖组多数LEC形态改变轻微 ,表现为胞浆基质密度轻度升高 ,部分线粒体水肿 ,细胞间间隙增宽。结论 :枸杞多糖可明显抑制LEC凋亡 ,从祖国医药中寻求防治白内障的有效药物具有广阔前景。 相似文献
40.
Observations on two members of the Swedish family with congenital dyserythropoietic anaemia,type III
S. N. Wickramasinghe A. Wahlin D. Anstee S. F. Parsons G. Stopps I. Bergstrom M. Eriksson H. Sandstrom S. Shiels 《European journal of haematology》1993,50(4):213-221
Abstract: Two affected individuals of the Swedish family with CDA, type III, in which the disease is transmitted as an autosomal dominant character, were studied. Both cases displayed features hitherto undescribed in this family but described in patients with CDA, type III, in whom the inheritance may have been as an autosomal recessive character. Such features were: (a) haemosiderinuria, (b) grossly disorganised erythroblast nuclei, (c) differences in the ultrastructural appearances of individual nuclei within the same multinucleate erythroblast and (d) intraerythroblastic inclusions resembling precipitated globin chains. In both cases the giant mononucleate erythroblasts and the multinucleate erythroblasts had total DNA contents up to 28c (1c = haploid DNA content) and 48c respectively, and some DNA synthesising bi- and multinucleate erythroblasts contained one or more nuclei which were unlabelled with 3H-thymidine. These findings are similar to those in patients with the autosomal recessive type of disease. Thus no major phenotypic differences are yet apparent between cases of CDA, type III, with different patterns of inheritance. Analysis of the surface erythrocyte proteins of the 2 Swedish CDA, type III, patients with monoclonal antibodies recognising Band 3, glycophorins A, B, C and D, Rh, CD44, CD47, CD55, CD58, CD59, Lutheran, Kell, LW and acetylcholinesterase did not reveal any gross abnormality of expression of these proteins. A slightly altered expression of blood group antigens A and H was revealed by the lectins Dolichos biflorus and Ulex europaeus and the Mr of Band 3 as judged by SDS polyacrylamide gel electrophoresis was also slightly reduced, suggesting that there may be minor alterations in the degree of N-glycosylation of some red cell membrane constituents. 相似文献