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1.
目的:探究马铃薯内生真菌次生代谢产物中新型倍半萜类化合物TA的抗炎作用.方法:脂多糖(LPS)刺激RAW264.7细胞建立体外炎症模型,通过测定细胞存活率、细胞NO的产生量、细胞内活性氧(ROS)水平,细胞培养上清液中肿瘤坏死因子-α(TNF-α)、白细胞介素-1β(IL-1β)的释放量、一氧化氮合成酶(iNOS),环氧合酶(COX-2)蛋白表达量,从而评价化合物TA的抗炎活性.结果:化合物TA对细胞无毒性,可剂量依赖性地抑制LPS刺激产生的NO,降低ROS水平,减少细胞炎症因子TNF-α和IL-1β的产生及下调iNOS,COX-2蛋白的表达量.结论:马铃薯内生真菌次生代谢产物中新型倍半萜类化合物TA具有显著的抗炎活性.  相似文献   

2.
目的:观察枸杞多糖(LBP)对脂多糖(LPS)致人脐静脉血管内皮细胞(HUVECs)损伤的保护作用,并探讨其可能的作用机制.方法:体外培养人脐静脉内皮细胞,分为空白对照组、LBP组、LPS模型组、LBP+LPS实验组,采用CCK-8法检测细胞活力,Western-blot法检测诱导型一氧化氮活酶(iNOS)、Caspase-3及NF-κB p65蛋白水平,ELISA法检测上清液TNF-α、IL-1β水平,Gries法测上清一氧化氮(NO)含量,硫代巴比妥酸法检测丙二醛(MDA).结果:与对照组相比,LPS模型组HUVEC增殖活力显著下降,NF-κB p65蛋白、iNOS、NO、TNF-α、IL-1β、MDA及Caspase-3水平显著升高,LBP处理则可部分增加受损内皮细胞的增殖活性,NF-κB p65蛋白、iNOS、NO、TNF-α、IL-1β、MDA及Caspase-3水平显著下降.结论:枸杞多糖对脂多糖诱导的人脐静脉内皮细胞损伤具有保护作用,与抑制NF-k B信号通路、抑制促炎因子TNF-α和IL-1β释放,抑制NO合成、减轻氧化应激,抑制凋亡蛋白Caspase-3表达有关.  相似文献   

3.
研究雷公藤红素(Celastrol)对大鼠胰岛细胞(INS-1)在炎症通路中功能损伤的恢复作用,并探索其分子药理学机制.通过MTT检测不同浓度Celastrol对炎症侵润下INS-1细胞的活性影响,利用免疫荧光技术观察INS-1细胞凋亡变化.采用钾离子刺激的胰岛素分泌(KSIS)来检验INS-1细胞分泌胰岛素的功能.ELISA检测INS-1细胞处理前后NO的分泌情况.结果发现,低浓度状态下Celastrol(100~300nmol/L)对有IL-1β引起的INS-1细胞凋亡有一定的保护作用,并且能显著改善INS-1的功能,INS-1细胞内NO分泌降低.研究结果表明Celastrol对INS-1细胞中NO分泌的抑制可能是其抑制INS-1细胞炎症状态下功能损伤的机制之一.  相似文献   

4.
观察紫花地丁提取物对脂多糖诱导的RAW 264.7巨噬细胞的抗炎作用并探讨其机制.采用脂多糖(1μg/mL)诱导RAW 264.7巨噬细胞建立体外炎症模型,格里斯试剂法和酶联免疫吸附法分别检测细胞上清液中的NO、TNF-α、IL-6、IL-1β的浓度,凝胶成像法检测细胞中iNOS、COX-2蛋白水平.结果显示,紫花地丁水提物、醇提物剂量依赖地降低脂多糖刺激巨噬细胞分泌NO、TNF-α、IL-6、IL-1β以及其iNOS、COX-2蛋白水平.相同剂量(100μg/mL)的紫花地丁醇提物抗炎活性优于水提物.结果表明,紫花地丁水提物、醇提物可抑制脂多糖刺激的RAW 264.7细胞炎症,其机制可能与抑制iNOS、COX-2蛋白表达,减少NO、TNF-α、IL-6、IL-1β等炎性因子的分泌有关.  相似文献   

5.
为研究2种石松属植物化学成分的抗炎活性,筛选具有较强抗炎活性的化合物,用LPS诱导RAW264.7细胞建立了体外炎症模型,采用MTT法检测了化合物对小鼠巨噬细胞株RAW264.7细胞增殖的影响.在安全浓度范围内(细胞存活率大于80%)给予药物干预,用Griess法检测了培养上清液中一氧化氮(NO)水平,以各化合物抑制NO释放的能力为筛选指标,评价了化合物的抗炎活性.结果表明:乙酰基二氢石松生物碱(16)、对香豆酸甲酯(21)、豆甾烷-3-酮-21-酸(22)具有较好的NO抑制率,并呈一定剂量依赖关系,提示它们具有一定的抗炎活性.  相似文献   

6.
目的:探究野漆树苷(Rhoifolin,RHO)对细菌脂多糖(lipopolysaccharide,LPS)诱导的小鼠单核巨噬细胞RAW264.7细胞炎症模型释放炎性因子的影响,并探讨其作用机制.方法:用脂多糖(0.5μg·mL~(-1))刺激体外生长良好的RAW264.7细胞24h建立体外细胞炎症模型,以MTT法测定不同浓度RHO对RAW264.7细胞的毒性作用,用Griess试剂法检测一氧化氮(Nitric Oxide NO)的含量,RT-PCR法检测细胞中肿瘤坏死因子α(Tumor Necrosis Factor,TNF-α),白介素1β(Interleukin-1β,IL~(-1)β),白介素6(Interleukin,IL-6)的含量,采用Western Blot法检测MAPK信号通路中相关蛋白的含量.结果:与空白对照组相比,在LPS诱导下,RAW264.7细胞分泌致炎因子NO,TNF-α,IL~(-1)β,IL-6(P0.01);与模型组相比,25~100μmol·L~(-1)的RHO可明显下调LPS诱导的RAW264.7细胞释放炎症因子NO,TNF-α,IL~(-1)β和IL-6(P0.05,P0.01),并呈现良好的剂量依赖关系;野漆树苷还不同程度的抑制了Erk和JNK激酶的磷酸化.结论:RHO可以抑制LPS所致的RAW264.7细胞炎症反应,减少炎症因子NO分泌,抑制TNF-α,IL~(-1)β和IL-6mRNA的合成,抑制JNK/SAPK及Erk信号通路可能是其抗炎作用机制之一.  相似文献   

7.
机体异常炎症反应与各种疾病的发生息息相关.实验室通过前期工作,筛选出抗炎效果较好的化合物,并将其命名为143.通过LPS诱导RAW264.7细胞和BV2细胞作为炎症细胞模型,用不同浓度的143处理细胞,观察其抗炎效应.用MTS检测不同浓度143对细胞活力的影响,NO试剂盒检测细胞培养上清NO含量的变化,Western blot检测NF-κB p-p65、iNOS、COX-2蛋白的表达情况.结果显示,143在浓度小于10μmol/L时对两种细胞活力没有影响;143在浓度为10μmol/L时能显著抑制细胞上清中NO的含量,并显著抑制细胞中炎症相关蛋白因子NF-κB p-p65、iNOS、COX-2的表达.  相似文献   

8.
采用LPS刺激小鼠单核巨噬细胞RAW 264.7释放炎症介质NO、PGE2以及IL-6、TNF-α等炎症因子,以MTT法评价细胞毒性,Griess法检测NO的含量,ELISA法检测PGE2、IL-6和TNF-α水平,Western blot法检测iNOS、COX-2及内参蛋白β-actin表达水平,研究黄芩素的抗炎活性及作用机制.测定黄芩素对DPPH自由基、超氧阴离子的清除活性,评价其抗氧化活性.结果表明,黄芩素能显著抑制炎症介质NO和PGE2的产生以及炎症因子TNF-α和IL-6的释放,明显下调iNOS、COX-2蛋白表达水平,对DPPH自由基、超氧阴离子均具有较强的清除活性,且呈良好剂量依赖关系.通过对黄芩素的抗炎、抗氧化作用的研究,可以为黄芩素及相关制剂的临床应用提供一定的理论依据.  相似文献   

9.
目的:探索高血压病血瘀证患者血清对内皮细胞功能及AMPK活性的影响.方法:高血压病血瘀证患者血清刺激人脐静脉内皮细胞(HUVECs)24 h,以高血压病非血瘀证患者血清作为对照.采用一氧化氮(NO)、内皮素(ET-1)检测试剂盒检测NO和ET-1的含量.Western blot法检测磷酸化一氧化氮合酶(e NOS)、总e NOS、细胞间黏附分子-1(ICAM-1)、血管细胞黏附分子-1(VCAM-1)、磷酸化AMPK及总AMPK的表达.定量PCR法检测肿瘤坏死因子(TNF-α)、白细胞介素-1β(IL-1β)的表达.结果:高血压病血瘀证患者血清处理24 h后,显著降低NO含量、抑制e NOS的活性、升高ET-1的含量,升高ICAM-1、VCAM-1的表达,升高单核细胞黏附率,升高内皮细胞TNF-α、IL-1β的表达水平,与高血压病非血瘀证患者血清相比,有统计学差异(P0.05).此外,高血压病血瘀证患者血清显著降低蛋白激酶AMPKα的磷酸化水平,与高血压病非血瘀证患者血清相比,有统计学差异(P0.05).结论:高血压病血瘀证患者血清能诱导内皮功能障碍和炎症反应,其机制可能与抑制AMPK的活性有关.  相似文献   

10.
为探讨岗松总黄酮(GSH)的抗炎活性机制,通过NF-κB信号通路,研究脂多糖(LPS)诱导RAW264.7细胞炎症的保护作用。实验采用噻唑蓝(MTT)法检测GSH对RAW264.7细胞增殖活性的影响,采用酶联免疫法(ELISA)检测GSH对白介素(IL-1β、IL-8)及转换生长因子β (TGF-β)的影响,采用蛋白印迹法(WB)检测细胞中IκBα蛋白相对表达,采用实时定量基因扩增荧光检测法(QPCR)检测细胞中NF-κB p65的mRNA基因表达。研究结果表明, GSH处理细胞后,可促进RAW264.7细胞增殖(P<0.05),抑制IL-1β、IL-8、TGF-β含量(P<0.01),上调IκBα蛋白的相对表达(P<0.05或P<0.01),抑制NF-κB p65的mRNA基因表达(P<0.01)。推测岗松总黄酮抑制NF-κB信号通路可能是其抗炎活性作用机制之一。  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.
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   

14.
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   

15.
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   

16.
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   

17.
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   

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.
The non-orthogonal localized molecular orbital(NOLMO)is the most localized representation of electronic degrees of freedom.As such,NOLMOs are thus potentially the most efficient for linear scaling calculations of electronic structures for large systems.However,direct ab initio calculations with NOLMO have not been fully implemented and widely used,partly because of the slow convergence issue in the optimization of NOLMO.We devel-  相似文献   

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