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81.
We investigated the synaptic connectivity of two populations of recoverin-labeled bipolar cells and GABAergic neurons in the inner plexiform layer (IPL) of the rat retina. Two types of cone bipolar cells, type 2 and type 8, were stained with anti-recoverin antibodies, and GABAergic neurons were stained with anti-glutamic acid decarboxylase (GAD) antibodies. Type 2 cone bipolar axons received synaptic input from amacrine cell processes in 177 cases; among these amacrine cell processes, 92 processes (52.0%) were GAD-like immunoreactive. A total of 159 amacrine cell processes, which are presynaptic to type 8 cone bipolar cells, were observed. Among these processes, 117 processes (73.6%) were GAD-like immunoreactive. The postsynaptic elements at the ribbon synapses of recoverin-labeled cone bipolar cells were observed in 482 processes. In both type 2 and type 8 cone bipolar cells, the major output was to amacrine cell processes. At the ribbon synapses of the type 2 cone bipolar cells, 224 of the postsynaptic profiles were amacrine cell processes, 97 processes (43.3%) were GAD-like immunoreactive. In type 8 cone bipolar cells, 45 processes (30.2%) of 149 amacrine cell processes were GAD-like immunoreactive. Our results provide morphological evidence that GABA is a major transmitter involved in the visual processing of type 2 and 8 cone bipolar cells and GABA may have a stronger influence on type 8 cone bipolar cells than type 2 cone bipolar cells in the IPL of the rat retina.  相似文献   
82.
Disorders of pyruvate carboxylase and the pyruvate dehydrogenase complex   总被引:3,自引:0,他引:3  
Summary The most common defect associated with deficiency of the pyruvate dehydrogenase (PDH) complex occurs in the E1 component, specifically due to mutations in the X-linked E1 gene. Clinical sequelae of these mutations, which range from severe neonatal lactic acidosis to carbohydrate-sensitive ataxia, can be different in males and females depending on the nature of the mutation and, in the case of females, on the X-inactivation pattern in different tissues. Males have a high representation of missense mutations among the patient cohort, while females are much more likely to have DNA rearrangements, particularly toward the 3 end of the coding sequence of the gene. Missplicing mutations involving exon 6 deletion have been reported, as has a missense mutation conferring true thiamin-responsiveness of the enzyme and the patient's clinical symptoms.Pyruvate carboxylase deficiency, on the other hand, is a true autosomal recessive disease, though it has high occurrences in particular ethnic groups, especially in Algonkian-speaking Amerindians and in Arabs. In the former group the defect is a simple type in which material cross-reactive to pyruvate carboxylase antibody is present in cultured cells (CRM+ve). In the latter group, cross-reacting material is rarely present (CRM–ve). The CRM+ve patients can survive into teenage years with careful supervision, while the CRM–ve patients have complications due to hyperammonaemia and dysfunction of the urea cycle and rarely survive beyond 3 months of life.  相似文献   
83.
84.
In this study we investigated the extent and time course of neuronal cell death and the regulation of the proliferating cell nuclear antigen (PCNA) in the different retinal cell layers following ischemia-reperfusion injury. Retinal ischemia was induced by controlled elevation of the intraocular pressure for a duration of 60 min. Changes in thickness and cell numbers in the retinal cell layers were analyzed at various time points (1 h to 4 weeks) after reperfusion. In parallel, apoptotic cell death was determined by the TUNEL method and the expression of PCNA analyzed by immunocytochemistry. In addition, we tested whether PCNA is expressed in neurons by double immunocytochemistry. The reduction in thickness was found to be less pronounced in the inner nuclear layer (INL). Correspondingly, cell numbers decreased by only 33% in the inner retina, but by more than 80% in the outer nuclear layer (ONL). Alterations in glial cell numbers did not contribute significantly to postischemic changes in the INL and ONL as assessed by using immunocytochemical markers for microglial and Müller cells. The time course of cell death determined by the TUNEL technique also differed markedly in the retinal layers being rapid and transient in the inner retina but delayed and prolonged in the ONL. PCNA immunoreactivity was undetectable in the normal retina, but was specifically induced in neurons of the inner retina within 1 h after reperfusion and was sustained for at least 4 weeks. We conclude that in contrast to photoreceptors in the ONL, a significant proportion of inner retinal neurons is resistant to ischemic insult induced by transiently increased intraocular pressure and that PCNA may possibly play a role in the selective postischemic survival of these cells.  相似文献   
85.
第二信使系统和其介导的基因表达对针灸效应影响的研究   总被引:2,自引:0,他引:2  
从微观水平研究针灸效应对揭示其机理有重要的意义。本文从第二信使系统和其介导的基因表达对针灸效应影响的研究方面综述了针灸效应的终结反映于细胞内生物效应的变化(即对机体不同器官组织细胞内的物质代谢调节 ) ,从一个侧面提示 ,针灸对机体各系统的调节作用最终是在细胞通过胞内信息传导系统实现的  相似文献   
86.
马春亮  程令梅 《新中医》2003,35(8):18-20
目的:观察疏肝起萎汤配合夫妻性感集中训练疗法治疗心因性勃起功能障碍的临床疗效。方法:将406例患者随机分为3组,治疗组147例采用疏肝起萎汤(由柴胡、枳壳、白芍、淫羊藿、蜈蚣、川芎、陈皮、炙甘草组成)配合夫妻性感集中训练疗法治疗;对照Ⅰ组132例采用疏肝起萎汤治疗;对照Ⅱ组127例采用家庭性感集中训练疗法治疗。观察3组综合疗效和症状改善情况。结果:治疗组痊愈99例,好转37例,痊愈率67.35%,总有效率92.52%;对照Ⅰ组痊愈49例,好转34例,痊愈率37.12%,总有效率62.88%;对照Ⅱ组痊愈53例,好转36例,痊愈率41.70%,总有效率70.08%。治疗组与对照Ⅰ组、对照Ⅱ组痊愈率、总有效率比较,差异均有显著性意义(P<0.05)。结论:疏肝起萎汤配合夫妻性感集中训练疗法治疗心因性勃起功能障碍,疗效确切。  相似文献   
87.
郑海洪  谷欣  谷春山  赵林山 《中成药》2003,25(3):220-222
目的:测定血能达片的急性毒性和验证其抗栓疗效及选药提供依据。方法:小白鼠一次Ig血能达26g/kg;五组动物分别给血能达(XND)3g/kg,溶栓胶种(RSC)1.25g/kg,复方丹参(CDDP)1.25g/kg,消栓通络(XSTL)2.5g/kg和NS Ig,qd 1次,连续7d。第7日药后1h,IV Collagen-Adr诱发血栓[1],观察死亡数;用毛细血管法测凝血时间,扭体法测痛。结果:小白鼠口服最大耐受量为26g/kg,临床用量的866.7倍;4种药物除消栓通络外,均有明显的抗栓作用(P<0.05-0.01);还证中、高剂量血能达尚有延长凝血时间和镇痛作用(P<0.05-0.01),其余3种药则没有。结论:血能达毒性小,具有溶栓胶囊,复方丹参等效的抗栓疗效,还能抗凝和镇痛。  相似文献   
88.
嗅觉诱发电位的实验研究   总被引:1,自引:0,他引:1  
目的:观察电刺激家兔嗅区黏膜记录的诱发电位的波形及其稳定性,探讨一种可以客观评价嗅觉功能的方法。方法:将双极刺激电极经家兔前鼻孔置于嗅区黏膜,给予电刺激,在颅顶记录嗅觉诱发电位(OEPs);改变刺激参数和部位,观察对电位潜伏期、阈值和波形的影响。结果:在颅顶前方近嗅球处记录到一组波形稳定的N1-P1-N23相复合波。潜伏期为:N1波20.6ms,P1波33.5ms,N2波58.3ms;改变刺激强度对各波无明显影响;改变刺激频率对各波影响较大,频率过高.波形分化较差。结论:正常OEPs是一组波形稳定的负-正-负3相复合波,波形稳定、重复性好,各参量可作为评价嗅觉功能变化的有用指标。  相似文献   
89.
迁移性咽和颈段食管异物4例   总被引:1,自引:0,他引:1  
目的:探讨迁移性咽和颈段食管异物的临床特征、诊断及治疗方法。方法:对位于腔壁内的异物,应尽量选用内镜下切开黏膜取出;若异物已移至腔外,则采用颈侧切开术。结果:4例患者均顺利取出异物,3例无并发症发生,1例声带麻痹。结论:颈部薄层CT扫描是证实异物迁移的重要手段,并对手术时定位异物有重要价值;食入异物出现迁移者,可产生致命性并发症,应及时处理。  相似文献   
90.
硫色满酮3位Mannich碱衍生物的合成及其抗真菌活性   总被引:1,自引:1,他引:1  
目的 设计、合成硫色满酮3位Mannich碱类化合物,并对其抗真菌活性进行初步评价。方法 以对氟苯硫酚为原料,经多步反应合成目标化合物,并测定目标化合物的抗真菌活性。结果共合成了10个未见文献报道的新化合物,经红外光谱、核磁共振氟谱及元素分析确证了其结构。其中化合物3对大部分供试真菌活性强于或相当于对照品克霉唑。结论 硫色满目3位取代Mannich碱具有较强的抗真菌活性。  相似文献   
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