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1.
为了研究慢性应激性抑郁发生中海马转化生长因子β1(transforming growth factor beta–1,TGF-β1)和硒蛋白P的作用及其关系,实验通过建立慢性不可预见性温和应激(Chronic Unpredictable Mild Stress,CUMS)动物抑郁模型,同时海马内微量注射TGF-β1以及TGF-β1型受体激酶抑制剂LY-364947,然后测量大鼠体重变化率,并通过糖水消耗以及旷场实验、悬尾实验检测大鼠行为变化,运用Elisa、Western blot分别检测大鼠海马组织内TGF-β1和硒蛋白P的含量变化.结果显示,与正常对照组相比,CUMS组大鼠表现出明显的抑郁样行为,海马组织内TGF-β1含量升高,硒蛋白P表达下降;正常大鼠海马内注射TGF-β1并不导致抑郁样行为,相反,CUMS同时海马内注射TGF-β1能逆转应激导致的抑郁样行为;正常和CUMS大鼠海马注射TGF-β1均能明显抑制硒蛋白P的表达;而应激的同时注射TGF-β1型受体激酶抑制剂LY-364947同样具有抗抑郁效应,此时硒蛋白P表达较CUMS组明显升高.以上结果表明:海马TGF-β1和硒蛋白P参与了应激性抑郁的发生;硒蛋白P对海马可能具有保护作用,TGF-β1通过TGF-β1型受体抑制硒蛋白P表达可能是导致抑郁发生的途径之一,而TGF-β1抗抑郁作用可能是经过TGF-β1型受体以外的其他途径实现.  相似文献   

2.
为证明慢性应激性抑郁的发生与应激引起的糖皮质激素(Glucocorticoids,GCs)分泌增加,导致海马脑源性神经营养因子(Brain Derived Neurothrophic Factor,BDNF)表达抑制有关.实验用大鼠通过建立慢性不可预见性温和应激(Chronic Unpredictable Mild Stress,CUMS)抑郁模型,通过海马微量注射皮质酮及糖皮质激素受体拮抗剂米司非酮,然后测量体重,观测行为学表现,并用酶联免疫吸附法检测海马内GCs和BNDF含量.结果显示:CUMS明显诱发大鼠抑郁样行为,海马组织中皮质酮明显升高,BDNF水平明显下降.海马微量注射米司非酮,使CUMS诱发的大鼠抑郁样行为明显改善,且BDNF水平明显升高.正常大鼠海马微量注射皮质酮后,表现出与CUMS组相似的抑郁样行为,且海马组织中BDNF明显下降.以上结果表明,慢性应激引起大鼠海马皮质酮明显升高,使海马BDNF表达明显减少,导致抑郁发生.糖皮质激素Ⅱ型受体(Glucocorticoids Receptor,GR)起着重要作用.  相似文献   

3.
大鼠抑郁症模型的建立与评价   总被引:2,自引:0,他引:2  
目的建立大鼠抑郁症模型并进行评价。方法将40只大鼠随机分为空白对照组、模型组,采用慢性、中等和不可预知应激刺激建立抑郁症模型,观查大鼠行为学指标:大鼠敞箱试验、糖水消耗试验、食物消耗量、去甲肾上腺素(NE)、5-羟色胺(5-HT)和皮质醇(CORT)水平。结果与正常组比较,模型组的水平得分垂直得分、糖水消耗、体重、进食量、NE、5-HT、CORT较空白组有明显差异(P〈0.05或P〈0.01)。结论采用慢性、中等和不可预知应激刺激建立的抑郁症模型符合抑郁症的特征,可作为抑郁症实验模型。  相似文献   

4.
本工作在22只大白鼠上,研究了刺激杏仁核对胃电活动的影响.结果表明,用一定强度的电刺激杏仁核后,胃电慢波振幅增大,同时快波振幅和频率也相应增加.这种效应在切断颈部双侧迷走神经后显暑减弱.因此,可以认为杏仁核参与了胃电的中枢性调节.推测其途径为杏仁核─—逃走神经背核和/或杏仁核─—下丘脑─—脑干网状结构等多个神经元接替通路,再由迷走传出而调节胃电活动.  相似文献   

5.
目的:观察4周自愿转轮运动对慢性应激致抑郁大鼠绝望行为及空间学习记忆能力和海马DG区nNOS表达的影响.方法:30只SD大鼠随机分为对照组、应激模型组及应激运动组,应激模型组及应激运动组大鼠建立慢性不可预见性应激(chronic unpredictable mild stress,CUMS)抑郁模型,同时应激运动组大鼠进行4周自愿转轮运动.运动及应激结束后通过强迫游泳实验及八臂迷宫实验等方法测试大鼠行为学指标变化,免疫组织化学法检测大鼠海马DG区nNOS神经元的表达.结果:(1)与对照组相比,慢性应激致抑郁大鼠强迫游泳实验中大鼠不动时间延长,八臂迷宫实验中应激大鼠完成八臂迷宫时间显著延长,工作记忆错误次数、参考记忆错误次数及总记忆错误次数均显著增加;海马DG区nNOS表达显著增强.(2)与应激模型组比较,应激运动组大鼠强迫游泳实验中大鼠不动时间缩短,八臂迷宫实验中应激运动组大鼠完成八臂迷宫时间显著缩短,参考记忆错误次数及总记忆错误次数均显著减少,海马DG区nNOS表达减弱.结论:自愿转轮运动可改善抑郁模型大鼠的绝望行为、提高大鼠学习记忆能力,机理可能与长期自愿转轮运动减弱抑郁大鼠海马DG区nNOS表达导致NO神经毒性减弱有关.  相似文献   

6.
建立慢性不可预见性抑郁动物模型,采用液体消耗实验(fluid consumption test,FCT)、敞箱实验(Open field test,OFT)和强迫游泳(Forced swimming test,FST)等方法进行行为学测试,并用免疫组织化学的方法检测海马BDNF和iNOS的表达,运用腹腔注射药物的方法探索BDNF和iNOS的作用与关系.探讨了海马脑源性神经营养因子(BDNF)和诱导型一氧化氮合酶(iNOS)在慢性应激诱导的抑郁症中的关系,及抑郁症的发病机制.与对照组相比,慢性不可预见性应激(Chronic unpredicted mild stress,CUMS)组大鼠的行为学表现能力下降,BDNF表达下降(n=8,P0.01),iNOS的表达升高(n=8,P0.01);阻断内源性BDNF大鼠的行为学表现能力也下降,iNOS的表达升高(n=7,P0.01);而海马微量注射iNOS的抑制剂SMT均可反转CUMS和BDNF抑制剂所导致的行为学表现能力下降的现象.慢性不可预见性应激引起海马BDNF表达下降,NO过高而导致抑郁.BDNF对神经元具有保护作用,BDNF的抗抑郁作用可能是通过抑制iNOS的表达而起作用的.提示BDNF等神经保护因子通过抑制iNOS的过量表达而保护脑组织可能是治疗抑郁症的一个重要途径.  相似文献   

7.
观察雌激素受体α(ERα)在正常大鼠和抑郁症模型大鼠海马中的分布.采用慢性不可预见性应激结合孤养方式构建抑郁症模型,Open-field法观察动物的抑郁行为,免疫组织化学方法观察海马神经元中ERα的分布.结果表明:与对照组相比,抑郁组大鼠水平运动、垂直活动和理毛次数显著减少(P0.01),体重增幅和糖水消耗量显著性下降(P0.01);在对照组和抑郁组,ERα免疫反应阳性神经元主要分布在海马的锥体层和颞叶皮层,DG区较少;与对照组相比较,抑郁组海马中ERα免疫阳性细胞数和染色强度均明显减少和降低;在对照组ERα染色主要位于神经元的胞核、胞质和/或突起,在抑郁组ERα染色主要位于神经元的胞质和突起,而位于胞核的则很少见.抑郁症的雌激素功能缺失或弱化机制,可能是应激诱导抑郁症过程中导致雌激素通过ERα核受体信号通路发挥神经保护作用的能力减弱.  相似文献   

8.
慢性不可预知和慢性束缚应激抑郁模型大鼠行为学研究   总被引:4,自引:0,他引:4  
采用慢性综合应激法配合孤养模型建立的应激模型和慢性束缚应激模型.观察模型组大鼠的行为学改变.实验结果表明,慢性综合应激结合孤养模型与空白组相比,大鼠的水平穿越格数(P<0.01)、竖立次数(P<0.01)、理毛次数均减少,中央格停留时间、粪便粒数均显著增加(P<0.01);大鼠体重明显减少(P<0.01);蔗糖溶液消耗量明显减少(P<0.01).慢性束缚模型大鼠的水平穿越格数、竖立次数、理毛次数和粪便粒数均减少;中央格停留时间显著增加(P<0.01);大鼠体重明显减少(P<0.05);蔗糖溶液消耗量明显减少(P<0.05).由此可见,慢性综合应激结合孤养模型组抑郁动物的各项行为学指标、体重变化及液体消耗量上均显示建模成功,而慢性束缚应激模型在行为学指标上无显著差异,但在体重、糖水消耗及糖水偏爱程度上均有显著差异.  相似文献   

9.
目的:观察槟榔十三味丸对抑郁模型大鼠行为学及下丘脑-垂体-肾上腺(HPA)轴的影响,探讨其抗抑郁作用及机制.方法:将40只SD雄性大鼠,根据蔗糖水消耗量及体重随机分成4组:空白对照组、慢性应激抑郁模型组、阳性药氟西汀组、槟榔十三味丸中剂量组,每组10只.除空白对照组外,其余均采用慢性不可预见性应激刺激加孤养诱导产生抑郁模型,造模同时ig给药,每日1次,连续给药21 d,各组均按10mL.kg-1给药,空白对照组、模型组ig等量去离子水.21 d后,采用敞箱实验、糖水消耗量检测和体重测量等指标评定大鼠行为学改变,并用放射免疫法检测大鼠下丘脑CRH,垂体ACTH和血清CORT的含量.结果:与空白对照组比较,模型组大鼠水平穿越格数、竖立次数、糖水消耗量、体重明显降低(P〈0.01或P〈0.05);与模型组比较,阳性药氟西汀组、槟榔十三味丸中剂量组水平穿越格数、竖立次数、糖水消耗量、体重明显升高(P〈0.01);放射免疫检测结果显示,与空白对照组比较,模型组大鼠下丘脑CRH,垂体ACTH和血清CORT的含量明显升高(P〈0.05或P〈0.01);与模型组相比,阳性药氟西汀组、槟榔十三味丸中剂量组下丘脑CRH,垂体ACTH和血清CORT的含量明显降低(P〈0.05或P〈0.01).结论:槟榔十三味丸可改善慢性应激抑郁模型大鼠行为学,具有一定的抗抑郁作用,并且抑制抑郁模型大鼠HPA轴的激活是槟榔十三味丸治疗抑郁症的机制之一.  相似文献   

10.
实验采用中缝大核(NRM)内微量注射、胃内压记录、针刺调节胃运动变化等方法,研究NRM相关神经递质、受体及细胞因子与电针影响大鼠胃运动之间的关系.结果显示,电针显著抑制胃收缩幅度,对胃收缩频率无影响.NRM内分别注入5-HT和IL-6均能加强针刺对胃收缩幅度的抑制效应.NRM内注入纳洛酮可反转针刺效应.NRM内注射L-NAME能加强针刺抑制胃收缩幅度的效应,而NRM内注射L-Arg则可减弱或反转针刺效应.结果表明,电针足三里穴可明显抑制胃收缩幅度,针刺效应可能是通过NRM中阿片肽实现的,并通过NO调节针刺效应.NRM中的5-HT及IL-6可影响针刺对胃收缩幅度的调节作用,神经、内分泌、免疫调节系统共同参与了针刺作用.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

15.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

16.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

17.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

18.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

19.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

20.
1 Rise of studies on climate change's effects on biodiversity
Until the 1980s, climate change and biodiversity were studied as two independent disciplines for more than a century. In 1992, the Ecological Society of America's annual report named climate change, biodiversity, and the sustainable ecological system as the three major global environmental issues of the twenty-first century [1].  相似文献   

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