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1.
It is well recognized that the world population is ageing rapidly. Therefore, it is important to understand ageing processes at the cellular and molecular levels to predict the onset of age‐related diseases and prevent them. Recent research has focused on the identification of ageing biomarkers, including those associated with the properties of the Golgi apparatus. In this context, Golgi‐mediated glycosylation of proteins has been well characterized. Additionally, other studies show that the secretion of many compounds, including pro‐inflammatory cytokines and extracellular matrix–degrading enzymes, is modified during ageing, resulting in physical and functional skin degradation. Since the Golgi apparatus is a central organelle of the secretory pathway, we investigated its structural organization in senescent primary human dermal fibroblasts using confocal and electron microscopy. In addition, we monitored the expression of Golgi‐related genes in the same cells. Our data showed a marked alteration in the Golgi morphology during replicative senescence. In contrast to its small and compact structure in non‐senescent cells, the Golgi apparatus exhibited a large and expanded morphology in senescent fibroblasts. Our data also demonstrated that the expression of many genes related to Golgi structural integrity and function was significantly modified in senescent cells, suggesting a relationship between Golgi apparatus function and ageing.  相似文献   
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对负压吸引装置便携方式的研究一直是急救医学追求的目标之一,因为它能够极大地促进急救成功率。文章基于这种需要,研制了一套便携式负压吸引装置,并根据实际应用效果,选择优化的制造材料。研制的便携式负压吸引装置主要由特殊设计的储液罐及罐盖、负压产生装置、过渡接头等部分组成,关键部件采用特殊材料制作,体积小,质量轻,操作简单,易于携带,完全能满足临床抢救及治疗的需要。作为一种急救中必不可少的器械,便携式负压吸引装置在急救伤病员运输、转运,家庭急救,及无动力源环境等情况下,对于抢救患者及提高救治效果,具有极大的竞争优势和应用前景。  相似文献   
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Summary This study was undertaken to elucidate, using the Golgi method, the neuropathological change in the brain of the macular mutant mouse, whose hemizygote (Ml/y) is considered to be a model of Menkes kinky hair disease (MKHD). The hemizygote mice gradually lost weight after 10 days of age and died with emaciation and seizure around day 15. The normal littermate (+/y) was well developed. In the cerebrum, the arborization of pyramidal neurons in the layer V of the Ml/y was the same as that in the +/y on day 10. However, development of arborization in the Ml/y was delayed in comparison with that in the +/y on days 12 and 14. Purkinje cells with several somal sprouts were observed in the cerebellum in both the Ml/y and +/y on day 7. The somal sprouts in the +/y had regressed gradually by day 12, while they were still in the anterior and middle lobes of the Ml/y on day 14. Additionally, the trunks of Ml/y stem dendrites became thicker and a cactus formation was recognized on the branching portion of the dendrites on day 14. Arborization of these abnormal Purkinje cells was distinctly poor compared with that in the +/y. These results suggest that the growth of the neurons is delayed in the Ml/y and simultaneously their cytoskeletal developments are disturbed, especially in the Purkinje cells. There is a close similarity in many respects to the neuropathological change in MKHD.  相似文献   
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指背腱膜的解剖学研究   总被引:1,自引:1,他引:0  
目的 探讨指背腱膜的构成特点及临床意义。方法 在30只成人尸体手标本上,通过模拟手术,对指背腱膜的构成特点进行了应用解剖学观测。结果 指背腱膜的构成复杂,其中的外侧腱束、外侧束、外侧腱和中央束在手指畸形的发生中有着特殊的临床意义。外侧腱束主要形成伸近节指间关节的功能解剖机制;其与外侧束形成的密切纤维联系而具有协同外侧腱的功能;该腱束与屈肌腱鞘有联系又使其具有平衡屈肌和伸肌肌力的作用。中央束在指背腱膜的整体协调、畸形的发生及矫正过程中起着重要的功能。结论 通过对指背腱膜的解剖研究,可以解释因指屈、伸肌腱平衡被破坏后所形成的畸形。  相似文献   
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The prenatal development of the mammalian neocortex has been analyzed, with the rapid Golgi method, in a variety of experimental animals (hamster, mouse, rat, and cat) and in humans. A new developmental conception of the structural organization of the mammalian neocortex is discussed. Neocortical development begins with the establishment of the primordial plexiform layer (PPL) which precedes and is a prerequisite for the subsequent formation of the cortical plate (CP). The formation of the CP occurs, in its entirety, within the PPL. During its development, three fundamental neuronal events occur: migration, early differentiation, and late maturation. All migrating neurons, travelling on radial glial fibers, reach layer I, develop an apical dendrite, and establish contacts with its elements. These newly differentiated neurons assume similar morphology resembling embryonic pyramidal cells. As such, an early differentiation stage common to all neurons of the CP is established. During the late maturation stage, all CP neurons acquire their specific phenotypic structural and functional features. Only pyramidal neurons retain and expand their original connections with layer I while other neuronal types lose these connections. The pyramidal cell is redefined in developmental terms: the neocortex's pyramidal cell is both structurally and functionally locked into position between layer I and the cortical depth of its soma. During mammalian evolution pyramidal cells are forced to structurally and functionally elongate their apical dendrite outwardly to accommodate an increasing amount of information without losing either their original anchorage to layer I or their cortical depth. This unique property of pyramidal neurons is considered to be a mammalian innovation. Based on these observations, a unifying developmental cytoarchitectonic theory applicable to all mammals is proposed. The theory considers the CP to be a mammalian innovation and to represent a single, stratified, and expanding telencephalic nucleus. The theory envisions the mammalian neocortex as an open biological system capable of progressive expansion by the recruitment and transformation of primitive neurons from upper layer II into pyramidal cells. Hence, the number of pyramidal cell strata increases over the course of mammalian phylogeny. The developmental roles of layer I in the migration of neurons, formation of the CP, unique morphology of pyramidal cells, and overall structural organization of the mammalian neocortex are emphasized.  相似文献   
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付璟 《西南军医》2007,9(4):11-12
目的观察WGLY-801型电脑肝病治疗仪对慢性乙型肝炎的治疗效果。方法随机选取慢性乙型肝炎患者144例,分为治疗组66例,在常规治疗基础上加用肝病治疗仪;对照组78例,采用常规治疗,观察两组治疗效果。治疗三疗程共45天(每疗程15天),观察临床症状、肝功能的动态变化,并对最终效果进行评价。结果经治疗后,两组患者临床症状、肝功能较前均有好转,但治疗组起效快,疗程明显缩短,疗效好,差异有明显统计学意义(p<0.05)。结论肝病治疗仪,操作简单,疗效确切,值得进一步推广应用。  相似文献   
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对人胎儿前庭器超微结构的研究,国内外报道甚少。本文对18至36周人胎儿颞骨10具进行了扫描电镜和透射电镜的观察,并对应用Surface preparation法制做人胎儿前庭器标本的方法进行了探讨。本文观察所见:豚鼠平衡斑的生理状态与人胎儿很近似,体面积比人胎儿平衡斑小,感觉毛长,细胞排列更整齐。28周以后的胎儿因前庭周围骨质变硬,制做标本时可以分别取出两囊斑和壶腹嵴。  相似文献   
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通过福田4500型B超软故障检修与分析,介绍了该机故障检修分析过程及造成该故障的原因。  相似文献   
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