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find Keyword "超微结构" 56 results
  • Study on abnormal dendrite of retinal ganglion cells in diabetic rats

    Objective To observe the morphological changes of dendrite and soma in retinal ganglion cells (RGCs) which subsisted in early diabetic rats. Methods The RGCs of 3-months-course diabetic rats and coeval normal rats were marked by gene gun techniques. To collect RGCs photographs by Leica microscope with Z axis and CCD camera;to observe the changes of diameter, variance of structural features in dendritic field and somata after classification which according to the size and morphology. Thy-1 antibody marks on the retinal RGCs, taking a photograph under fluorescent microscope, counting the changes of retinal RGCs density in early diabetic rat. Results In three-month diabetic rats,the density of retinal RGCs was decreased obviously. Morphological changes of RGCs in the dendritic fields were observed with gene gun technique. There was no severe variation in all kinds of the bole of cell dendrite, in which some only showed crispation partially and sparseness also twisting in the dendritic ramus. The mean diameter of dendritic field and soma in class A of diabetic rats was (401plusmn;86) mu;m, the mean diameter of dendritic field in control group was (315plusmn;72) mu;m,compared with each other, there is statistically significant differences (t=21.249,Plt;0.001); the mean diameter of soma in class A of diabetic rats was (24plusmn;6) mu;m, the mean diameter of soma in control group was (22plusmn;5) mu;m, compared with each other, there is no statistically significant differences (t=0.927,Pgt;0.05); the mean diameter of dendritic field and soma in class B of diabetic rats were (170plusmn;36)、(14plusmn;2) mu;m respectively, in control group were (165plusmn;36)、(16plusmn;2) mu;m, the mean diameter of dendritic field and soma in class C of diabetic group were(265plusmn;78)、(17plusmn;5) mu;m respectively, in control group were (251plusmn;57)、(17plusmn;4) mu;m , compared with each other, there are on statistically significant differences(t=1.357,0.798,0.835,1.104,Pgt;0.05). Conclusions In short-term diabetes, the survived RGCs show good plasticity in adult diabetic rats, especially in class A. The changes of dendrites were more sensitive than the soma, which could be the leading index of the morphologic changes of RGCs in the early stage. The good plasticity showed by the RGCs and the time window from changing in dendrite to cell death provide us many evidences not only for the research but also for the nerve protection in clinic. (Chin J Ocul Fundus Dis,2008,24:249-254)

    Release date:2016-09-02 05:46 Export PDF Favorites Scan
  • 供者心脏热缺血后收缩力、三磷酸腺苷、超微结构的关系

    目的 探讨三磷酸腺苷(ATP)作为衡量供者心脏保存质量指标的可靠性,以及ATP、心肌收缩力、超微结构三者的关系.方法 新西兰大白兔24只,随机分为4组,1组:热缺血0分钟,低温保存1小时;2组:热缺血0分钟,低温保存3小时;3组:热缺血5分钟,低温保存3小时;4组:热缺血10分钟,低温保存1小时,每组6只大白兔.测定ATP含量和观察超微结构,然后置于Langendorff模型上,用氧合自体温血再灌注15分钟,测定心肌收缩力.结果 1组收缩力和ATP分别为缺血前的84.67%和78.8%;2组为70.5%和57.7%;3组为32.67%和50.7%;4组为21.67%和49.7%.1组超微结构呈轻~中度可逆损伤改变,2组呈中度可逆损伤改变;3组和4组呈重度不可逆损伤改变.结论 ATP是衡量供者心脏功能能否恢复的重要指标,ATP、心肌收缩力、超微结构三者密切相关.

    Release date:2016-08-30 06:35 Export PDF Favorites Scan
  • OBSERVATION ON THE RETINAL HISTOPATHOLOGY AND 1TS ULTRASTRUCTURE IN A PATIENT WITH RETINITIS PIGMENTOSA.

    PURPOSE:To study the retinal pathologic changes and pathogenesis of relinhis pigmenlosa(RP). METHODS:The relina from a patient with autosomal dominant RP was examined by light and electron microscopy. RESULTS:Degeneration and structure disturbance almost involved in every layer of retina and were accompanied hy regional differenecs:Posterior region was more than periphery one in severity. Degeneration of retinal pigment epithelium(RPE)closely eorrelaled to that of the phmoreceplor. The uhraslrneture of the retina showed extensive and severe degeneration in the photoreeeptors ,particularly ill omer segments and mitoehondrlas. Lipofusein gramdes were accumuhtted in the cytoplagm. CONClUSIONS:These changes suggested that self-energizing system and self engulfing system of the photoreceptols were disfunctloned. (Chin J Ocul Fundus Dis,1997,13: 24-26)

    Release date:2016-09-02 06:12 Export PDF Favorites Scan
  • AESTRACTS THE STUDY OF COMBINED DXM AND HAPARIN ON ULTRAMICROSTRUCTURE OF MDSCLE AND MICROCIRCULATION DURING DELATED REPLANTATION OF LIMB

    rough the ultramicroscopic observation on muscle and microcirculation, Group A,where a largeamount of DXM combined with heporin was given svstematically and locally into the femoral artery of the severed limb before replantation, and in Group B only heporin was given, and Group C and D ascontrol.The results showed that if the hormone and heparin were administred in large dosage, it wasadvantageous to reduce the tissues from reperfusion injury during delayed replantation.

    Release date:2016-09-01 11:18 Export PDF Favorites Scan
  • EFFECTS OF VERAPAMIL AND ENERGY COMPOUNDS ON STRUCTURAL AND FUNCTIONAL CHANGES OF SMALL BOWEL′S IN RABBITS

    Objective To probe the change of the structure and function of the small bowel by injection of different drugs (verapamil, energy compounds or normal saline) via the superior mesenteric artery (SMA) injections.Methods The model of the small intestine ischemia/reperfusion (I/R) injury was made in grey rabbits. Free calcium concentration in mitochondria of the small intestine was determined, and the ultrastructural change was also observed by electron microscopy at the very time of occlusion, 60 minutes after occlusion and 30 minutes after reperfusion. Results The free calcium concentration in mitochondria was more declined in verapamil group (2.976±0.410 nmol/mg.prot) than in N.S. group (4.234±0.542 nmol/mg.prot), P<0.01, at 60 minutes after occlusion. At 30 minutes after reperfusion, free calcium concentration in mitochondria was more decreased in energy compunds group (2.401±0.323 nmol/mg.prot) and verapamil group (3.847±0.610 nmol/mg.prot) than in the N.S. group (5.981±1.031 nmol/mg.prot). Conclusion Verapamil and energy compouds have protective effects on the functions and ultrastructures of the I/R of small intestine.

    Release date:2016-09-08 02:00 Export PDF Favorites Scan
  • EFFECT OF CRUSHING OF SCIATIC NERVE ON NEURON OF LUMBAR SPINAL CORD

    In order to investigate the effect of nerve compression on neurons, the commonly used model of chronic nerve compression was produced in 48 SD rats. The rats were sacrificed in 1, 2, 3, 4, 5 and 6 months after compression, respectively. The number of neuron and ultrashruchure of alpha-motor neurons and ganglion cells of the corresponding spinal segment were examined. The results showed as following: After the sciatic nerve were crushed, the number of neuron and ultrastructure of alpha-motor neurons and ganglion cells might undergo ultrastructural changes, and even the death might occur. These changes might be aggravated as the time of crushing was prolonged and the compression force was increased. It was concluded that for nerve compression, decompression should be done as early as possible in order to avoid or minimize the ultructural changes of the neuron.

    Release date:2016-09-01 11:07 Export PDF Favorites Scan
  • 逆行性灌注浅低温氧合血心脏不停跳与冷血心脏停搏液对cTn I的影响

    目的 对比研究逆行性灌注浅低温氧合血心脏不停跳与低温冷血心脏停搏液对外周血清心肌肌钙蛋白I(cTn I)的影响. 方法 将18例双瓣膜置换术患者分为心脏不停跳组和心脏停搏组,观察围手术期外周血清cTn I、肌酸激酶(CK)、肌酸激酶同工酶(CK-MB)及主动脉阻断前后用透射电子显微镜观察心肌超微结构变化.结果 心脏不停跳组主动脉开放后各个时相点CK虽略低于心脏停搏组,但差别无显著性意义(Pgt;0.05);主动脉开放后6小时CK-MB明显低于心脏停搏组(Plt;0.05),主动脉开放后各个时相点心脏不停跳组cTn I明显低于心脏停搏组(Plt;0.05).两组患者主动脉阻断前心肌超微结构均有轻度改变,主动脉阻断90分钟心脏停搏组心肌超微结构损伤较心脏不停跳组明显. 结论 逆行性灌注浅低温氧合血心脏不停跳围手术期外周血清cTn I较低,可能与该方法使体外循环期间发生不可逆损伤的心肌细胞较少,心肌超微结构损伤较轻有关.

    Release date:2016-08-30 06:32 Export PDF Favorites Scan
  • The histochemistry changes in rat retinal photochemical damage of rat

    Objective:To observe the histochemical changes of retinal photochemical damage in rats. Methods:The changes of retinal ultrastructure were observed.The concentration of malondaldehyde(MDA) was tested and the activity the histochemical change of cytochrome oxidase (CCO) and (Mg ++ -ATPasw) were evaluated on the retnal photochemical damage in SD rats. Results:At the 6th hour after light exposure,the swelling appwared at the nuclei of photoreceptor,the mitochondria of inner segment.The apical microvilli of RPE disappeared and lysosomes increased in RPE.On the 6th day after light exposure,the changes became more obvious.While on the 14th day after light expose the nuclei of photoreceptors and the inner segments renewed but the arrangement of the disk was lose;and the microvilli appeared of the disk was lose;and the microvilli appeared at the tip of RPE.The Activity of CCO and Mg ++ -ATPase decreased and MDA increased in retina at the 6th hour and on the 6th day and they recovered on the 14th day after light exposure. Conclusion:Lipd peroxidation that broke the cell membrane system of photoreceptor which induced changes of the cell ultrastru cture abd the activity of enzyme might relate to pathogenesis in retinal photochemical damage. (Chin J Ocul Fundus Dis,1998,14:38-40)

    Release date:2016-09-02 06:11 Export PDF Favorites Scan
  • L-精氨酸对乳猪深低温停循环脑代谢与结构的影响

    目的 通过深低温停循环(DHCA)转流模型,研究左旋精氨酸(L-arg)在低温缺血时对脑代谢和结构的影响. 方法 采用上海种白猪,3~4周龄,随机均分成4组: L-arg组,左旋硝基精氨酸甲酯(L-NAME)组, L-arg+L-NAME组和对照组,每组10只.按临床方法行心肺转流术,于转流前、降温末、复温末和转流结束等分别测定颈内静脉一氧化氮(NO)、脑皮质三磷酸腺苷(ATP)和颈内静脉乳酸含量.并行脑组织学和超微结构观察. 结果 降温末L-NAME组和对照组NO含量较其它两组明显下降(Plt;0.01).复温末,除L-NAME组外,其余3组均恢复至转流前水平(Plt;0.01),L-arg组NO水平在复温末较转流前高(Plt;0.01). 转流开始后大脑皮质ATP即有明显下降,L-arg组下降幅度最小,且在复温末已接近转流前水平;L-NAME组下降幅度最大(Plt;0.01). 转流开始后颈内静脉乳酸含量即升高,L-arg组和L-arg+L-NAME组上升幅度较小;降温末和转流结束乳酸含量较其它两组低(Plt;0.01). 大脑皮质组织学和超微结构检查显示,大脑皮质细胞结构变化L-arg组和L-arg+L-NAME组较对照组和L-NAME组轻. 结论 深低温停循环手术时,应用L-arg具有较好的脑保护作用,而L-NAME有脑损害作用.L-arg可部分逆转DHCA时L-NAME对脑组织的损害作用.

    Release date:2016-08-30 06:32 Export PDF Favorites Scan
  • Ultrastructural characterization of macular pucker

    Objective To study the ultrastructure of macular puck er (MP) from the patients with rhegmatogenous retinal detachment (RRD) and the mechanism associated with its development. Methods Twenty specimens of MP surgically removed by vitrectomy from 13 patients were dissected into two layers in each of them.The ultrastructure of two layers,i,e,near the vitreous and near the retina,was studied with electron microscopy. Results Seven sections of the near vitreous ones appeared prodominant collagen deposits and a few of epithelial like cells,and pigment particles might be present in the cytoplasm.While cells with foot processes were found in 13 membrane sections near the retina and increasing number of various types of cells rich in collagen around were observed including fibroblast like cells and glial cells. Conclusion The findings suggest that the MP after surgery of retinal detachment may possess a characteristic lamination,and posterior hyaloid cortex was involved in the developmetn of MP. The adhesion between posterior hyaloid cortex and macular area might be a key factor for forming MP. (Chin J Ocul Fundus Dis, 2001,17:52-54)

    Release date:2016-09-02 06:03 Export PDF Favorites Scan
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