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目的:探讨丹酚酸A对大鼠脑缺血/再灌注(cerebral ischemia/reperfusion,CI/R)损伤及抗氧化酶活性的影响。方法:采用大鼠脑中动脉闭塞(middle cerebral arteryocclusion,MCAO)2 h再灌注24 h模型。实验终末,检测脑梗死面积,脑水肿以及评价神经功能损伤,并进一步分析脑组织中三种抗氧化酶的活性水平。结果:与模型组相比,丹酚酸A组大鼠脑梗死面积显著减少(P0.05),水肿程度显著减轻(P0.05),神经功能学评分显著下降(P0.05)。模型组再灌注24 h后,SOD,GSH-PX及CAT活性显著下降(P0.05);丹酚酸A组SOD,GSH-PX及CAT活性则显著升高(P0.05)。结论:丹酚酸A对大鼠CI/R损伤具有保护作用,可能与CI/R损伤时的脑组织SOD,GSH-PX及CAT活性显著升高相关。  相似文献   
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目的初步分离和鉴定力竭运动诱导的大鼠睾丸金属结合蛋白(testis metal-binding proteins,TMB-Ps)。方法 8只雄性SD大鼠一次性力竭游泳运动(8只对照)后6 h取睾丸和肝脏组织,用镉饱和法测定TMBPs和肝脏金属硫蛋白(metallothionein,MT)含量,用tricine-SDS-PAGE方法分离镉饱和法提取液的TMBPs组分和肝脏MT,用液相色谱-串联质谱法(LC-MS-MS)鉴定TMBPs分离条带。结果力竭运动组大鼠TMBPs水平(113.71±11.72)nmol Cd/g testis显著高于安静对照组(87.14±12.72)nmol Cd/g testis(P0.01),肝脏MT表达量(64.70±14.89)μg/g也显著高于安静对照组(7.32±3.31)μg/g(P0.001)。LC-MS-MS对tricine-SDS-PAGE分离的蛋白条带的鉴定结果为:TMBPs含有泛素、铜-锌-超氧化物歧化酶、酪蛋白样磷蛋白等蛋白质,另外还应包括MT。结论TMBPs由一组具有金属结合性、耐热性和诱导性的蛋白质所组成,主要有泛素、超氧化物歧化酶和酪蛋白样磷蛋白。镉饱和法并非测定金属硫蛋白的特异性方法。  相似文献   
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The translational efficiency of the coat protein gene of phage MS2 has been examined in vivo with respect to neighbouring sequences. The cloned MS2 DNA has been gradually shortened starting at the 5' or 3' terminus, and its effect on coat protein synthesis monitored. Removal of the 3'-terminal sequences had little influence. In contrast, the gradual removal of the 5'-terminal region profoundly reduces translation. Long before the ribosomal binding site (RBS) of the coat protein (CP) gene is reached, the yield of CP has dropped by one order of magnitude. Functional half-lives of the various messengers were found not to be significantly different. Available evidence indicates that the secondary structure of the RBS in native and shortened MS2 RNA is identical. We infer that important determinants for ribosome recognition lie 5' to the RBS region of the MS2 RNA coat gene.  相似文献   
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Adult male Sprague-Dawley rats were administered bombesin (BN) intracerebroventricularly (ICV), at a dose of 0.001, 0.01, 0.1, or 1.0 μg, and the behavioural effects monitored longitudinally across time for up to 24 hr. Administration of BN significantly increased the locomotor, rearing and grooming activity at all doses. The time-course of behavioural activation was dose-related (lasting up to 2.5 hr). There was no significant difference in the behavioural response of rats receiving the BN doses in an ascending or descending order. To test the effects of dopamine receptor blockade on the BN-induced behavioural changes, groups of animals were treated with fluphenazine or haloperidol (0.1 to 2.5 mg/kg, IP) 30 min prior to BN (1 μg, ICV) administration. The results revealed that the neuroleptics could effectively antagonize the BN-induced activation of locomotor, rearing and grooming activity. These data are concordant with the view that centrally administered BN stimulates spontaneous exploratory and grooming behaviours in rats, in a time- and dose-related manner. Furthermore, since neuroleptics block these effects, it remains possible that the BN-induced behavioural changes may be mediated, at least in part, through the dopaminergic system(s).  相似文献   
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借助基因芯片获取慢性酒精中毒大鼠海马相关基因的表达数据集,通过生物信息学的分析方法对差异表达基因进行筛选与分析。从分子水平揭示慢性酒精中毒对大鼠大脑海马体的影响,为慢性酒精中毒的损伤机制以及相关疾病发病机制的基础研究与临床治疗提供新的方向。同时,还通过Y迷宫实验对实验大鼠的学习记忆功能进行了检测,借助电镜拍摄其线粒体。结果显示,我们一共筛选出208个差异表达基因,其中51个表达上调,157个表达下调。其中涉及的主要信号通路有氧化磷酸化通路、D-谷氨酰胺和谷氨酸代谢通路、阿尔茨海默病信号通路、帕金森病信号通路、膀胱癌信号通路、B细胞受体信号通路和亨廷顿病信号通路等。由此我们得出结论,慢性酒精中毒可能影响了海马多个基因的表达,其中包括Rpsa、Wdr31、Rps11、Rps9、Ndufa2、Mrto4、Rpl6、Dap3、Ndufb8、Ndufb6、Ephb2、Cox6c、Prkcd、Rela、Raf1、Ubd、Mrps28、Mrpl35等关键基因,进而损伤了电子传递链复合体Ⅰ,最终损伤线粒体,导致大鼠学习记忆能力的损伤。  相似文献   
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Influence of spleen deficiency rat model to observe the Fusen herbal tea.MethodsRats were gavaged 15% rhubarb powder suspension (5 mL) of 17 days, twice a day. It caused by the spleen deficiency rats model, rats model are respectively at the same time drinking large doses of Fusen herbal tea, a small dose of Fusen herbal tea, a high dose of Wang Laoji herbal tea, a small dose of Wang Laoji herbal tea. When modeling will replace the corresponding tea rat normal blank group were given normal drinking water instead of daily water, and Baohewan group given a pill solution. In the 17 days, Rats were killed and observe the changes of rats.ResultsRat model were successded in spleen deficiency. The pathological changes of the organs in the model group, the pathological changes of the organs in the model group, but every dose of Fusen herbal tea has no obvious effect on rats.ConclusionFusen herbal tea has no obvious effect on rats.  相似文献   
59.
Moist Exposed Burn Ointment (MEBO®) is widely used topical agent applied on skin burn. This study investigated the effect of MEBO topical application on activation and proliferation of epidermal stem cells through the immunohistochemical localization of cytokeratin 19 (CK19) as a known marker expressed in epidermal stem cells. Biopsies from normal skin and burn wounds were taken from 21 patients with partial thickness burn 1, 4, 7, 14, 21, and 28 days after treatment with MEBO. Tissue sections were prepared for histological study and for CK19 immunohistochemical localization. In control skin, only few cells showed a positive CK19 immune-reaction. Burned skin showed necrosis of full thickness epidermis that extended to dermis. Gradual regeneration of skin accompanied with an enhancement in CK19 immune-reactivity was noted 4, 7, 14 and 21 days after treatment with MEBO. On day 28, a complete regeneration of skin was observed with a return of CK19 immune-reactivity to the basal pattern again. In conclusion, the enhancement of epidermal stem cell marker CK19 after treatment of partial thickness burn injuries with MEBO suggested the role of MEBO in promoting epidermal stem cell activation and proliferation during burn wound healing.  相似文献   
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目的 探讨半夏总生物碱(total alkaloids from Pinellia Ternate,TAPT)对帕金森病模型大鼠的防治作用及其抗氧化机制.方法 采用脑内定位注射6-羟基多巴胺(6-OHDA)建立帕金森病大鼠模型,在模型建立成功的同时给予半夏总生物碱预防性治疗.采用Morris水迷宫进行帕金森病大鼠的行为学检测,用化学比色法检测大脑皮质及血清超氧化物歧化酶(SOD)活力、丙二醛(MDA)、过氧化氢(H2O2)和还原型谷胱甘肽(GSH)的含量.结果 与正常组比较,帕金森病模型组大鼠的逃避潜伏期明显延长(P<0.01),跨越平台次数明显减少(P<0.01);经半夏总生物碱治疗组,大鼠逃避潜伏期明显缩短(P<0.05,P<0.01),跨越平台次数明显增加(P<0.01).帕金森病模型组大鼠脑皮质及血清中MDA、H2O2的含量增加,SOD活性及GSH的含量降低(P<0.01);经半夏总生物碱治疗组,脑皮质MDA、H2O2的含量显著减少(P<0.01),皮质GSH、SOD含量显著增加(P<0.01);半夏总生物碱给药组中低浓度组、中浓度组血清MDA的含量无统计学意义(P>0.05),高浓度组血清MDA含量下降(P<0.01),各治疗组中血清H2O2含量明显下降(P<0.01),血清GSH含量显著增加(P<0.01).结论 半夏总生物碱具有改善学习记忆能力,对抗大鼠神经系统的退行性变有一定的作用,可能通过改变帕金森病模型大鼠皮质部分及血清SOD、GSH的含量,而抑制了MDA和H2O2的产生.  相似文献   
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