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111.
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   
112.
探讨keratin 13基因在喉癌发生中的作用。方法在keratin 13基因内部及附近选择5个微卫星引物进行LOH分析,于DNA水平间接检测100例喉癌患者中该基因的缺失情况。结果5个STR位点均存在LOH,其中D17S1964E、D17S2092、D17S791、D17S1665及D17S808位点的LOH频率分别为30.48%、26.02%、21.62%、37.66%和21.51%,以D17S1665位点的LOH频率最高,杂合性丢失与临床分期无显著相关。结论Keratin13基因在喉癌的发生中具有重要作用,具体机制有待进一步研究。  相似文献   
113.
目的 通过研究枸橼酸能否减轻一水草酸钙(calcium oxalate monohydrate,COM)晶体对体外培养的Wistar大鼠肾小管上皮细胞造成的损伤,以探讨枸橼酸在尿路结石防治中的作用及其机制。方法分离、培养正常雄性Wistar大鼠的肾小管上皮细胞,在原代培养第5天时,将细胞分成3组(空白对照组、COM组及枸橼酸组),分别于各组培养液中培养2h后用比色法测定各组细胞培养基中丙二醛(malonaldehyde,MDA)的含量及细胞的钙镁ATP酶(Ca`2+-Mg`2+-ATPase)和钠钾ATP酶(Na`2+K`+-ATPase)的活性。结果①COM组和枸橼酸组细胞Ca2+-Mg`2+ATPase和Na`++K`+-ATPase活性均明显低于对照组(P〈0.05);②与枸橼酸组相比,COM组细胞Ca`2+-Mg`2+-ATPase和a`++K`+-ATPase活性下降更加明显(P〈O.05);③COM组和枸橼酸组细胞培养基中MDA的含量均明显高于对照组(P〈O.05);④与枸橼酸组相比,COM组细胞培养基中MDA的含量更高(P〈O.05)。结论外源性枸橼酸能够减轻一水草酸钙晶体对体外培养的Wistar大鼠肾小管上皮细胞造成的脂质过氧化损伤。  相似文献   
114.
目的 探讨诊断电镜(DEM)对脾原发性淋巴瘤的病理分型的超微结构特征。流式细胞术(FCM)测定瘤细胞DNA倍性与恶性程度的关系。方法 应用透射电镜和流式细胞术观察分析41例脾原发性淋巴瘤的超微结构和瘤细胞DNA倍性。结果41例脾原发性淋巴瘤中霍奇金淋巴瘤5例,电镜下R-S细胞呈双叶不规则核和对称致密大核仁,核内常染色质明显,胞质内见中等量线粒体,较长的粗面内质网。非霍奇金B细胞性淋巴瘤21例,裂细胞性5例,细胞核大,核伴有较深的裂沟,胞浆少,胞质见少数肿胀线粒体,无核裂细胞性7例,细胞核规则,呈圆或卵圆型,异染色质多呈条块状,核仁中等大,胞质少,见少量线粒体及长粗面内质网。混合细胞性,瘤细胞大小悬殊,大畸形核较多,核扭曲,不规则深沟及不对称分叶,形成多叶核。非霍奇金T免疫母细胞淋巴瘤11例,瘤细胞较大,核小胞质相对多,胞质透明,核多形性,有的呈圆或卵圆形,核膜薄,有深浅不一的凹陷,可见小核仁。淋巴母细胞性5例,淋巴母曲核性淋巴瘤,细胞为中小形,呈锯齿状核和扭曲状核,异染色质沿核膜聚集,核仁小。毛细胞性淋巴瘤1例,毛细胞的绒毛宽基底,核仁大,胞浆无核糖体板层复合物。组织细胞性淋巴瘤3例,细胞浆丰富,核圆或椭圆形,偶见核膜呈锯齿状或折叠,线粒体和溶酶体丰富,无细胞连接和Birbeck颗粒。FCM  相似文献   
115.
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   
116.
双侧内囊前肢毁损术治疗难治性强迫症疗效及随访研究   总被引:9,自引:0,他引:9  
目的 对难治性强迫症进行双侧内囊前肢毁损术治疗 ,评定手术疗效并进行 2年随访 ,以进一步探索脑外科手术对难治性强迫症的疗效 ,并探讨手术治疗的良好适应症。方法 对 2 8例难治性强迫症患者进行双侧内囊前肢毁损术治疗 ,并分别在手术前、手术后二周、手术后三月、手术后六月、手术后一年、手术后二年进行Y BOCS、HAMA、HAMD量表评定及术后疗效评定。结果  (1)强迫症患者手术后各期Y BOCS评分、HAMA评分与手术前比较均下降 ,有极显著差异 (P <0 .0 0 1) ;(2 )手术后各期Y BOCS的强迫思维评分均有明显下降 (P <0 .0 0 1) ,强迫行为在手术后 1年和 2年 ,与手术前比较无明显改变 (P >0 .0 5 ) ;(3)手术后 2年的总有效率为 5 3.5 % ,明显低于手术后 3月的总有效率 (P <0 .0 1)。结论 采用双侧内囊毁损术有相当的治疗效果 ,对于难治性强迫症患者可作为一种补充治疗手段 ;手术治疗对强迫行为的长期疗效较差 ,以严重的强迫思维为主的难治性强迫症患者为手术更好的适应症。  相似文献   
117.
左半结肠癌并发急性肠梗阻一期切除吻合的合理性与评价   总被引:21,自引:3,他引:18  
目的 探讨左半结肠癌并发急性肠梗阻一期切除吻合的合理性与评价。方法 回顾性分析我院1994年2月期间至2003年2月采用一期切除吻合术治疗左半结肠癌并发急性肠梗阻64例的l临床资料。结果 全组患者无死亡及腹腔感染。7例(10.9%)发生切口感染,3例(4.7%)发生吻合口漏,均治愈。住院时间10~36d,平均16d。结论 部分经选择的病例中开展一期切除吻合术是安全、可行的,选择性应用一期切除吻合术是治疗左半结肠癌并发急性肠梗阻的理想术式。  相似文献   
118.
We describe the enhancement patterns of myoepithelioma in two patients with a soft palate mass. In the first case, helical CT revealed a faintly enhancing mass. Histologically, the tumor was composed of plasmacytoid cells in a background of rich myxoid stroma. Immunostaining for CD34 showed scanty blood vessels. In the second case, helical CT revealed an intensely enhancing mass. Histologically, the mass was a cellular tumor with fibrous stroma. Immunostaining for CD34 also showed frequent blood vessels.  相似文献   
119.
Objective: To summarize the clinical outcomes of 117 human vitrified blastocyst transfer cycles and to determine the impact factors.Methods: In IVF-ET cycles, supernumerary embryos were cultured to 5-Day(D5) or 6-Day(D6), blastocysts of various stages were cryopreserved by vitrification using cryoloops. Survival rate and clinical pregnancy rate were observed.Results: A total of 312 blastocysts were thawed in 117 frozen embryo transfer cycles, the survival rate was 90.7% (283/312) after thawing. After the transfer of 230 blastocysts in 115 cycles, 69.6% (80/115) of the women got clinically pregnant, and 17.5% (14/80) of them suffered from miscarriage, 39 healthy babies were born in 28 deliveries, and the other 38 pregnancies are ongoing. The implantation rate was 47.4% (109/230). In 107 transfer cycles with 2 hatched blastocysts transferred in each cycle, 72.9% (78/107) got clinically pregnant, while in 8 cycles with 1 or no hatched blastocysts in the two transferred blastocysts, the clinical pregnancy rate is 25%(2/8). The clinical pregnancy rates were not statistically different between natural (77.4%, 24/31) or artificial endometrium preparation (66.7%, 56/84) cycles. Conclusions: These findings suggest that blastocyst vitrification is effective in terms of implantation rate and pregnancy outcome. Transferring of two hatched blastocyst can achieve a higher pregnancy rate.  相似文献   
120.
目的:研究脑缺血后脑片[Ca2+]i变化。方法:采用新型Ca2+荧光指示剂Fura-2双波长法测定兔大脑中动脉阻塞(MCAo)局灶脑缺血后脑片细胞内游离钙([Ca2+]i)。结果:脑缺血后脑组织[Ca2+]i显著升高。结论:[Ca2+]i在脑缺血损害中起重要作用。  相似文献   
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