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11.
螯虾尾神经节光敏神经元反应的适应特性及信号通路检测   总被引:2,自引:1,他引:1  
520nm光照诱发克氏原螯虾尾神经节光敏神经元反应,发现2min后出现明显适应现象。适应期间,用550nm检测光刺激引起的效应随适应发展逐渐减弱。胞外高[Mg2+]不抑制此光敏反应;高[Mg2+]、高[Ca2+]均显著增加适应速率;低[Na+]显著降低适应速率,但能被胞外高[Ca2+]所拮抗。检测光敏神经元的上行传入通路,未见通过下咽神经节,提示可能有中枢启动运动反射环路。统计239例成体螯虾光敏神经元反应检出率,提示在发育过程中存在作为光感受器的光敏及适应潜能的保留或消亡机制。  相似文献   
12.
为了建立脊髓背根神经节(dorsal root ganglion,DRG)切除模型,选择性地使感觉神经纤维溃变而保持运动神经纤维的正常功能,从而为周围神经趋化性再生的定量评价提供有效的研究方法。将雄性SD大鼠20只,随机分为两组,每组10只动物。大体解剖组:解剖大鼠坐骨神经的神经根组成及DRG的位置。DRG切除组:切除支配大鼠坐骨神经的每个神经根的DRG。观察大鼠DRG切除后步态变化及足部溃疡情况。切除后3周,取双侧坐骨神经、胫神经、腓神经及腓肠神经行髓鞘染色,观察各神经中感觉神经纤维溃变情况;行美兰复红染色,计算机图像分析,运动神经纤维计数。发现大鼠坐骨神经由L4、L5、L6神经干组成,DRG位于腹、背侧根汇合处近心端1mm处。DRG切除术后,大鼠步态失去协调性,但展趾宽度无明显改变。DRG切除后3周,髓鞘染色显示腓肠神经中有髓神经纤维髓鞘完全溃变,坐骨神经、胫神经、腓神经中部分有髓神经纤维发生溃变。美兰复红染色、计算机图像分析计数显示坐骨神经及三个主要分支内,有髓运动神经纤维分别占其总数的58.4%、54.6%、45.4%、0。说明DRG切除模型,可以有效区分感觉和运动神经纤维,能够较好地定量评价周围神经趋化性再生的效果。通过比较不同桥接材料和不同修复方法的错接率,从而定量评价各修复材料和方法的趋化性再生效果。  相似文献   
13.
The brain and the thoracic ganglion of a crustacean can synthesize and secrete gonad-stimulating hormone (GSH) which stimulates the maturation of gonad. In the previous experiments, sex steroid hormones (estradiol, testosterone, progesterone, etc.) have been detected from the crustacean. However, the feedback regulation of sex steroid hormones on the brain and the thoracic ganglion of the crustacean has not been reported so far. In the present experiment, monoclonal antibodies were applied to investigate the immunorecognition of estrogen receptor (ER) and androgen receptor (AR) in the brain and the thoracic ganglion mass of Scylla paramamosain. The results showed that the distribution of the immunopositive substances of ER and AR was extremely similar. They distributed in the protocerebrum, deutocerebrum and tritocerebrum of the brain, and mainly in protocerebrum. In the thoracic ganglion mass, immunopositive substances distributed in the subesophageal ganglion, thoracic ganglion and abdominal ganglion, and mostly in subesophageal ganglion. Immunopositive substances of ER and AR mostly existed in the cytoplasm of neurons. The present study will provide morphological evidence for the origin and the evolution of ER and AR. In addition, the immunoreactivities of ER and AR suggested that the estrogen and androgen may be involved in the feedback regulation of crustacean neuroendocrine.  相似文献   
14.
Long chain polyunsaturated fatty adds, i. e., docosahexaenoic acid (DHA or C22 : 6n - 3), amchidonic acid (AA or C20 : 4n -6) have been identified as essential fatty acids and play an important role in growth and development of infants. Measurement of fatty acid composition is usually by collection of blood, but to obtain blood in infants is difficult. Nowadays, the fatty acid composition can be estimated by collecting buccal mucosal cells, which can avoid repeated blood sampling. The of this paper is to compare the fatty acid composition of cheek cells with that of plasma and red blood cells (RBCs). In this study, twenty-seven infants were enrolled, and buccal mucosal cells and blood samples were obtained from these infants of the same time. Fatty acid composition of buccal mucosal cells, plasma and RBCs were measured by capillary gas chromatography. The results show that the contents of AA and DHA in the buccal macosal cells are correlated well with that in the plasma [r=0.36 (P=0.042) and r =0.38 (P =0.033), respectively]. The ratio of AA to DHA is 1.32% in buccal mucosal cells, 1.60% in plasma and 1.55% in RBCs and there are no significant differences among groups (P = 0.134). It shows that the fatty acid composition in buccal macosal cells can reflect the fat nutrition status in infants and can be detected by capillary gas chromatography. Estimating fatty acid composition of buceal mucosal cells in infants by capillary gas chromatography is feasible, and because of its noninvasiveness, it can be suitable for nutrition research in infants.  相似文献   
15.
将90例带状疱疹患者分为三组:A组为头面部及上肢患者组,采用行星状神经节阻滞;B组为胸腹部患者组,采用硬膜外隙注药;C组病变部位与B组相同,采用皮肤科常规综合治疗。结果表明:接受星状神经节阻滞和硬膜外给药,A,B组止痛优良率分别为90%和93.3%;C组优良率仅为40%。A,B组平均病程为12.4d和11.8d,C组平均病程为17.2d。A,B组与C组相比较,差异具有统计学显著性(P<0.05)。结果表明:星状神经节阻滞和硬膜外隙注药比皮肤科综合治疗止痛效果好,且具有使患者缩短病程、康复快的临床效果。  相似文献   
16.
The mammalian olfactory system is not uniformly organized but consists of several subsystems each of which probably serves distinct functions. Not only are the two major nasal chemosensory systems, the vomeronasal organ and the main olfactory epithelium, structurally and functionally separate entities, but the latter is further subcompartimentalized into overlapping expression zones and projection-related subzones. Moreover, the populations of ‘OR37’ neurons not only express a unique type of olfactory receptors but also are segregated in a cluster-like manner and generally project to only one receptor-specific glomerulus. The septal organ is an island of sensory epithelium on the nasal septum positioned at the nasoplatine duct; it is considered as a ‘mini-nose’ with dual function. A specific chemosensory function of the most recently discovered subsystem, the so-called Grueneberg ganglion, is based on the expression of olfactory marker protein and the axonal projections to defined glomeruli within the olfactory bulb. This complexity of distinct olfactory subsystems may be one of the features determining the enormous chemosensory capacity of the sense of smell.  相似文献   
17.
目的观察三叉神经慢性缩窄环术大鼠半月节射频热凝的大体及镜下改变,探讨射频热凝温度和时间与半月神经节损伤的关系。方法36只成年雄性SD大鼠,随机选取33只建立慢性缩窄性损伤三叉神经痛模型。建模成功2周后,随机分为3组:射频热凝组(R组,n=24),假手术纽(S组,n=6),热凝对照纽(C组,n=3)。经中颅窝开颅暴露半月神经节,R组行半月节穿刺热凝,根据温度、时间随机分为8个小组,每组3只,分别为:65℃120″、180″组,70℃120″、180″组,75℃120″、180″组,80℃120″、180″组。S组仅行半月节穿刺不热凝,按留针时间分为120″、180″两组;C组不行半月神经节穿刺及热凝。余3只SD大鼠作为正常对照组(N组)。R组及S组热凝或穿刺结束即取出大鼠半月神经节,C组、N组直接取出半月神经节,观察半月神经节大体变化,游标卡尺测量神经节毁损区直径,光镜下观察神经节细胞的变化。结果S组、C组与N组比较,大鼠半月神经节大体及光镜下均无明显变化。R组在65℃时大鼠半月节大体及镜下无明显损伤;70℃时开始在肉眼及镜下出现损伤;75℃、80℃时半月节则出现明显凝固区,毁损区直径测量较70℃组明显增大(P〈0.01),光镜下神经元细胞核出现不同程度的固缩改变。毁损温度越高、时间越长,损伤范围越大,程度越重。结论75℃、80℃射频热凝可导致神经节细胞明显变性,损伤程度及范围随温度升高、时间延长逐渐加重与增大。  相似文献   
18.
莫宁  王鲁  陈家欢  陈美芳 《广西科学》1997,4(4):306-308
应用细胞内生物电记录方法,观察神经肽P物质(SP)对大鼠星状神经节能细胞的影响,用灌流或用加压向细胞周围施加SP可使部分细胞发生膜除极反应,用低钙或用含河豚毒素克氏液灌流神经节,并不影响SP引起的除极反应的幅度和时程。SP引起除极反应的同时常伴有膜电阻增大,当膜电位增大时,除极化反应幅度变小,反转电位为-80mV至-100mV,研究表明,SP对部分星状神经节细胞具有直接兴奋作用,并且SP对细胞膜的  相似文献   
19.
20.
从中国大陆产银环蛇毒纯化得到两个K-神经毒素:Ⅵ26及Ⅷ1b峰,其中Ⅵ2d峰的部分氨基酸顺序与K-银环蛇毒素结构均一。Ⅵ26及Ⅷ1b峰在浓度分别为150nmol/L及200nmol/L经30分钟可完全阻断小鸡睫状神经节的烟碱传递,表明这两个K-神经毒素均为高效神经元烟碱乙酰胆碱受体拮抗剂。以Affi-gel401亲和层析柱纯化的电鳐烟碱受体在严格的脂-蛋白比例下重构至人工微团上,以 ̄(86)Rb ̄+内流至荷有烟碱乙酰胆碱受体的囊泡来衡量离子通道功能.测定了α-银环蛇毒素及K-神经毒素对受体离子内流的抑制作用.毒素(μmol)与受体(μmol)比值为0.5时,α-银环蛇毒素100%阻断氨甲酰胆碱作用下的受体离子内流。10倍于此浓度的K-神经毒素对离子通道活动无影响。  相似文献   
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