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1.
目的:研究面神经撞击伤后面神经核内生长相关蛋白(GAP-43)的变化及高压氧(HBO)治疗的影响。方法:利用BIM-Ⅱ型生物撞击机致家兔右侧面神经干损伤,应用SP免疫组化染色法观察损伤后1、3、7、14和21天(分别用HBO治疗及不用HBO为对照)面神经核内GAP-43的变化,并用电镜观察面神经干超微结构变化。结果:面神经损伤第1天,伤侧面神经核区GAP-43样免疫反应性神经元(GLIN)开始增多,第14天其增多达到高峰,第21天逐渐下降。HBO治疗组伤后不同时期GLIN的增多明显高于对照组。伤后第21天,与对照组相比HBO组面神经干电镜观察可见较多的新生髓鞘。结论:HBO治疗可使伤后面神经核内GLIN增多,因而有助于面神经损伤后的修复与再生。  相似文献   
2.
Nerve regeneration during healing of Achilles tendon rupture in the rat was studied by immunohistochemistry including semi-quantitative assessment. Neuronal markers for regenerating and mature fibers, ie., growth associated protein 43 (GAP-43) and protein gene product 9.5 (PGP 9.5), respectively, were analyzed at different time points (1-16 weeks) post-rupture. In the paratenon, both the ruptured and intact contralateral tendon (control) consistently exhibited immunoreactivity to the two neuronal markers. However, in the proper tendinous tissue only the ruptured tendon showed immunoreactivity to GAP-43 and PGP 9.5. This expression was seen already at week 1 post-rupture to reach a peak at week 6 followed by a successive drop till week 16. Also the occurrence of sensory and autonomic fibers according to immunoreactivity for calcitonin gene-related peptide (CGRP) and neuropeptide Y (NPY), respectively, was analyzed. CGRP-positivity was abundantly seen from weeks 2-6 in both perivascular and sprouting free nerve endings in the proper tendon tissue undergoing healing. NPY appeared later, at weeks 6-8 post-rupture around blood vessels mainly located in the surrounding loose connective tissue. Apart from a role in vasoaction (CGRP, vasodilatory; NPY, vasoconstrictory). both neuropeptides have been implicated in fibroblast and endothelial cell proliferation required for angiogenesis. The present study shows that early healing of ruptured tendons is characterized by an orchestrated, temporal appearance of nerve fibers expressing peptides with different actions. The observed pattern of neuronal regeneration and neuropeptide expression may prove to be important for normal connective tissue healing.  相似文献   
3.
The canine's olfactory acuity is legendary, but neither its main olfactory system nor its vomeronasal system has been described in much detail. We used immunohistochemistry on paraffin-embedded sections of male and female adult dog vomeronasal organ (VNO) to characterize the expression of proteins known to be expressed in the VNO of several other mammals. Basal cell bodies were more apparent in each section than in rodent VNO and expressed immunoreactivity to anticytokeratin and antiepidermal growth factor receptor antibodies. The thin layer of neurone cell bodies in the sensory epithelium and axon fascicles in the lamina propria expressed immunoreactivity to neurone cell adhesion molecule, neurone-specific beta tubulin and protein gene product 9.5. Some neurones expressed growth-associated protein 43 (GAP43): and a number of those also expressed neurone-specific beta tubulin-immunoreactivity. Some axon fascicles were double labelled for those two proteins. The G-protein alpha subunits Gi and Go, involved in the signal transduction pathway, showed immunoreactivity in the sensory cell layer. Our results demonstrate that the canine vomeronasal organ contains a population of cells that expresses several neuronal markers. Furthermore, GAP43 immunoreactivity suggests that the sensory epithelium is neurogenic in adult dogs.  相似文献   
4.
We report on the expression of growth associated protein (GAP)43 and neural cell adhesion molecule (NCAM) in congenital fibre type disproportion (CFTD) with myopathological additional signs of interstitial myositis. We assume that sarcolemmal GAP43 in developmental disordered myocytes plays a role in maintenance of growth morphology. In muscular dystrophy light microscopical evaluation reveals no GAP43 immunoreactivity in regenerating fibres. The expression of GAP43 seems to be a characteristic feature of CFTD. The expression of NCAM, particularly in the sarcolemma of small muscle fibres of CFTD, indicates a functional state of permanent partial denervation. Whether the steroid-responsive interstitial myositis is pathogenetically related to CFTD or a coincidental inflammation is not known. Because of the clinical and myopathological data the differential diagnosis of Emery-Dreifuss muscular dystrophy is considered.  相似文献   
5.
Summary The ccs1-1 mutation of Saccharomyces cerevisiae, which has been previously described, is associated with an increase in cytochrome content, in respiration, and in ATP synthesis. In addition, this mutation leads to the same phenotype as cells de-regulated in the cAMP pathway. From a yeast genomic library, we have isolated a DNA fragment in a recombinant plasmid pCD1 which complements the ccs1-1 mutation. Homologous integration of this DNA in the genome occurs at the CCS1 locus. An 11 kb of the DNA insert is necessary for complementation. Sequencing part of the fragment identifies CCS1 as the IRA2 gene. The IRA2 gene is known to encode an attenuator of RAS gene product activity which stimulates the GTPase activity of the RAS proteins. This result underlines the involvement of cAMP-dependent phosphorylation in mitochondrial function. We present the sequence of 1 kb DNA upstream of the putative ATG of the IRA2/CCS1 gene product which is devoid of an ORF and could contain several regulatory sites.  相似文献   
6.
The canine's olfactory acuity is legendary, but neither its main olfactory system nor its vomeronasal system has been described in much detail. We used immunohistochemistry on paraffin-embedded sections of male and female adult dog vomeronasal organ (VNO) to characterize the expression of proteins known to be expressed in the VNO of several other mammals. Basal cell bodies were more apparent in each section than in rodent VNO and expressed immunoreactivity to anticytokeratin and antiepidermal growth factor receptor antibodies. The thin layer of neurone cell bodies in the sensory epithelium and axon fascicles in the lamina propria expressed immunoreactivity to neurone cell adhesion molecule, neurone-specific beta tubulin and protein gene product 9.5. Some neurones expressed growth-associated protein 43 (GAP43): and a number of those also expressed neurone-specific beta tubulin-immunoreactivity. Some axon fascicles were double labelled for those two proteins. The G-protein alpha subunits Gi and Go, involved in the signal transduction pathway, showed immunoreactivity in the sensory cell layer. Our results demonstrate that the canine vomeronasal organ contains a population of cells that expresses several neuronal markers. Furthermore, GAP43 immunoreactivity suggests that the sensory epithelium is neurogenic in adult dogs.  相似文献   
7.
B R Ransom  H Kettenmann 《Glia》1990,3(4):258-266
Evidence of electrical and dye coupling between oligodendrocytes and astrocytes was sought in cultures of mouse spinal cord. Cell identity was verified using cell specific antigenic markers. In most experiments current was injected into oligodendrocytes while recording voltage in nearby astrocytes. Nine of 17 oligodendrocyte-astrocyte cell pairs showed weak electrical coupling; the average estimated coupling ratio was 0.03 +/- 0.06 (cf. 0.11 for oligodendrocyte-oligodendrocyte and 0.44 for astrocyte-astrocyte pairs; Kettenmann and Ransom: Glia, 1: 64-73, 1988). Application of 0.5 mM BaCl2 or 44.6 mM CsCl depolarized astrocytes and oligodendrocytes and was estimated to increase the coupling ratio between these cells 3-5-fold; these effects were rapid in onset and completely reversible. In 5 of 7 cases, oligodendrocyte-astrocyte pairs that appeared uncoupled in normal solution exhibited coupling during Ba++ or Cs+ exposure. The actions of these cations are believed to be mediated by blockade of glial K+ channels. Depolarization, per se, as induced by increasing [K+]o, did not increase coupling ratio. The fluorescent dye lucifer yellow (LY) was injected into 10 oligodendrocytes, 8 of which were electrically coupled to nearby astrocytes, and never passed into astrocytes in detectable quantities. Likewise, astrocytes injected with LY stained other astrocytes, but never oligodendrocytes. These findings document the presence of weak electrical coupling between astrocytes and oligodendrocytes, in the absence of dye coupling. Weak coupling of this sort could subserve metabolic interactions between these cells mediated by the passage of small but important molecules such as cyclic AMP, but would not allow strong electrical interactions. If such coupling among glial cells is widespread, it would constitute a "metabolic syncytium" that could serve to coordinate glial behavior.  相似文献   
8.
中药材GAP种植基地建设探讨   总被引:3,自引:1,他引:3  
中药材GAP种植基地建设是影响药材生态经济效益的关键因素之一。在基地建设中应重视量化基地环境因子,以地选材,以材定地,完善栽培方法,深入研究加工工艺,实行规范的“公司十基地十科研单位十农户”的经营运作方式。运用系统论概念,将基地建成最大效益的生态经济复合体。  相似文献   
9.
本文对中药材认证的法规和管理体系做了简要说明,对中药材生产过程中的规范化要求及其应开展的主要工作进行了探讨。分析了影响中药材质量的主要生产技术环节及其认证要求。介绍了GAP认证对人员、设备和档案的要求,并对认证准备工作中需要建立的文件、资料和档案系统提出了建议。  相似文献   
10.
药材生产标准操作规程相关共性关键技术   总被引:4,自引:0,他引:4  
通过主持完成科技部中药现代化研究及产业化开发项目“龙胆等三种中药材规范化种植研究”(已通过国家验收 )过程中 ,对在制定相应药材 (龙胆、防风、五味子 )的 SOP时涉及的一些相关共性技术进行了深入探讨。一些共性技术如病虫害有效防治技术、采收及其方法 ,以及质量控制的技术需通过加大中药材相关的基础研究力度方能解决 ,而有一些问题要在应用开发上下功夫。  相似文献   
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