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41.
Glial glutamate transporter-1 (GLT-1) plays an essential role in removing glutamate from the extracellular space and maintaining the glutamate below neurotoxic level in the brain. To explore whether GLT-1 plays a role in the acquisition of brain ischemic tolerance (BIT) induced by cerebral ischemic preconditioning (CIP), the present study was undertaken to observe in vivo changes in the expression of GLT-1 and glial fibrillary acidic protein (GFAP) in the CA1 hippocampus during the induction of BIT, and the effect of dihydrokainate (DHK), an inhibitor of GLT-1, on the acquisition of BIT in rats. Immunohistochemistry for GFAP showed that the processes of astrocytes were prolonged after a CIP 2 days before the lethal ischemic insult, which could protect pyramidal neurons in the CA1 hippocampus against delayed neuronal death induced normally by lethal ischemic insult. The prolonged processes extended into the area between the pyramidal neurons and tightly surrounded them. These changes made the pyramidal layer look like a 'shape grid'. Simultaneously, the prolonged and extended processes showed a great deal of GLT-1. Western blotting analysis showed significant upregulation of GLT-1 expression after the CIP, especially when it was administered 2 days before the subsequent lethal ischemic insult. Neuropathological evaluation by thionin staining showed that DHK dose-dependently blocked the protective role of CIP against delayed neuronal death induced normally by lethal brain ischemia. It might be concluded that the surrounding of pyramidal neurons by astrocytes and upregulation of GLT-1 induced by CIP played an important role in the acquisition of the BIT induced by CIP.  相似文献   
42.
矢状缝早闭(舟状头)全颅成形术   总被引:2,自引:1,他引:1  
目的探讨治疗矢状缝早闭(舟状头)畸形的手术方法。方法采用David“‖”形颅缝重建法(6例)、旋转骨瓣截骨法(2例)、梅花颅骨瓣头颅盖成型法(3例)等术式对舟状头进行矫治。结果11例患儿均治愈,外形满意。结论1~3个月舟状头宜采用简单的David“‖”形颅缝重建法进行治疗,3个月以上的患儿可选用浮动颅骨瓣头颅成型术、梅花瓣法颅骨瓣头颅盖成型术等方法进行治疗。  相似文献   
43.
目的:评价直肠癌根治术中用Foley尿管气囊压迫治疗骶前静脉丛大出血(MPVP)的临床价值。方法:分析1995~2005年用Foley尿管气囊压迫治疗骶前静脉丛大出血6例的临床资料。结果:6例骶前大出血中全部用Foley尿管气囊压迫控制出血,术中出血量为800~1700mL,Foley尿管于术后4d拔除3例,5d1例,6d2例,均无再出血,会阴切口均一期愈合。结论:Foley尿管气囊压迫治疗骶前静脉丛大出血是一种简单安全有效的治疗方法。  相似文献   
44.
The present study was designed to detect three single nucleotide polymorphisms (SNPs) located on 22q11 that was thought as being of particularly importance for genetic research into schizophrenia. We recruited a total of 176 Chinese family trios of Han descent, consisting of mothers, fathers and affected offspring with schizophrenia for the genetic analysis. The transmission disequilibrium test (TDT) showed that of three SNPs, rs10314 in the 3'-untranslated region of the CLDN5 locus was associated with schizophrenia (chi(2) = 4.75, P = 0.029). The other two SNPs, rs1548359 present in the CDC45L locus centromeric of rs10314 and rs739371 in the 5'-flanking region of the CLDN5 locus, did not show such an association. The global chi-square (chi(2)) test showed that the 3-SNP haplotype system was not associated with schizophrenia although the 1-df test for individual haplotypes showed that the rs1548359(C)-rs10314(G)-rs739371(C) haplotype was excessively non-transmitted (chi(2) = 5.32, P = 0.02). Because the claudin proteins are a major component for barrier-forming tight junctions that could play a crucial role in response to changing natural, physiological and pathological conditions, the CLDN5 association with schizophrenia may be an important clue leading to look into a meeting point of genetic and environmental factors.  相似文献   
45.
6186例脑卒中患者发病时间的季节性分析   总被引:3,自引:0,他引:3  
目的探讨青岛市区脑出血(CH)、脑梗死(CI)、蛛网膜下腔出血(SAH)发病时间的季节规律。方法收集青岛市1998年~2002年脑卒中患者6186例,其中CH1179人,CI4821人,SAH186人。圆分布分析探讨脑卒中患者发病时间的季节规律。结果CH冬季高发,平均角在1月份(P<0.05),男性患者的平均角在2月份(P<0.05),女性患者的平均角在1月份(P<0.05);CI秋季高发,男、女间无差别,平均角在10月份(P<0.05);SAH秋季高发,平均角在10月份(P<0.05),男性患者的平均角在9月份(P<0.05),女性患者的平均角在10月份(P<0.05)。结论青岛市的脑卒中发病具有季节性,在脑卒中预防工作中要充分考虑其发病的季节特点,并采取相应的措施。  相似文献   
46.
不同脑缺血和再灌流过程中大鼠脑组织NO含量的动态变化   总被引:12,自引:0,他引:12  
采用线栓法制成大鼠大脑中动脉梗塞 ( MCAO)模型 ,依 Hb O2 - NO法测定持续性脑缺血和缺血 /再灌流脑组织内 NO含量的变化 ,以探讨不同脑缺血和再灌流过程中 NO的变化规律及其意义。结果 :缺血 3小时受损脑组织 NO水平即增高 ,再灌流后 NO逐步升高 ,而持续性缺血状态下 NO则表现降低后再升高的变化。虽然两组 NO在 7天时均有明显降低 ,但仍高于缺血前水平。认为持续性脑缺血和缺血 /再灌流情况下 NO的变化规律有所不同 ,与缺血脑组织的缺氧及产生 NO所需底物供应缺乏有关 ,且可能与脑组织的损害密切相关  相似文献   
47.
48.
BACKGROUND AND PURPOSE: We investigated the chemical identity of the endothelium-derived relaxing factor generated by acetylcholine in cerebral microvessels by studying the effects and mechanism of action of inhibitors of nitric oxide synthesis from arginine on the vasodilation and endothelium-derived relaxing factor production induced by topical application of acetylcholine in cerebral arterioles. METHODS: We determined cerebral arteriolar dilation and endothelium-derived relaxing factor production by bioassay in anesthetized cats equipped with cranial windows during superfusion of 10(-7) M acetylcholine before and after administration of either NG-monomethyl L-arginine or NG-nitro-L-arginine, two inhibitors of nitric oxide synthesis. RESULTS: NG-Nitro-L-arginine abolished the vasodilation from acetylcholine and eliminated the production of endothelium-derived relaxing factor in the bioassay experiments. NG-Monomethyl L-arginine had no effect on the response to acetylcholine in the absence of pretreatment. However, after pretreatment with the detergent sodium dodecyl sulfate to increase cell membrane permeability, the inhibitor had effects identical to those of NG-nitro-L-arginine. L-Arginine reversed the effects of the inhibitors of nitric oxide synthesis. Neither inhibitor affected baseline vascular caliber, nor did they generate a vasoconstrictor agent in the bioassay experiments. The two inhibitors of nitric oxide synthesis did not affect the response to nitroprusside or adenosine, showing that the effect on responses to acetylcholine was specific. Also, the blockade of the response to acetylcholine induced by the inhibitors of nitric oxide synthesis was unaffected by treatment with superoxide dismutase and catalase, showing that the effect was not mediated by oxygen radicals. CONCLUSION: The endothelium-derived relaxing factor generated by acetylcholine in cerebral arterioles of cats is either nitric oxide or a nitric oxide-containing substance. The effect of these inhibitors on the response to acetylcholine is mediated by inhibition of the synthesis of nitric oxide. There is no involvement of radicals, and no vasoconstrictor agent is generated.  相似文献   
49.
A limited flip angle gradient-echo 3D volume acquisition imaging protocol for mapping partial pressure of oxygen (pO2) in perfluorocarbon compounds (PFCs) at low field (0.14 T) is presented. The pO2 measurement method is based on the paramagnetic effect of dissolved molecular oxygen (O2) which reduces the PFC 19F T1? Specific objectives related to imaging of PFCs through use of the protocol include improved image signal-to-noise characteristics and elimination of 19F chemical shift artifacts. A parametric Wiener deconvolution filtering algorithm is used for suppression of 19F chemical shift artifacts. Application of the protocol is illustrated in a series of calculated pO2 maps of a gas equilibrated, multi-chamber phantom containing perfluorotributylamine (FC-43). The utility of the protocol is demonstrated in vivo through images of a commercially available perfluorocarbon based blood substitute emulsion containing FC-43 sequestered in the liver and spleen of a rat.  相似文献   
50.
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