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1.
大豆甙元磺酸盐对豚鼠离体回肠收缩的影响及途径分析   总被引:2,自引:0,他引:2  
实验采用豚鼠回肠离体肠段,置于装有Krebs液的恒温灌流浴槽中,记录肠段收缩活动,探讨大豆甙元对消化道平滑肌的作用及其作用机理.结果表明,大豆甙元磺酸盐对豚鼠离体回肠收缩有明显抑制作用,纳洛酮能减弱大豆甙元磺酸盐对回肠的抑制作用,心得安、酚妥拉明、阿托品均不影响大豆甙元磺酸盐对回肠平滑肌的作用.实验结果提示,大豆甙元能抑制回肠平滑肌的收缩活动,其作用部分由μ-受体介导.  相似文献   

2.
紫红獐牙菜对在体及离体肠肌的影响   总被引:2,自引:0,他引:2  
目的:研究紫红獐牙菜对豚鼠离体肠肌及小鼠小肠推进功能的影响。方法:采用炭末推进法、离体标本运动实验法分析紫红獐牙菜对在体及离体肠肌的作用及可能的机理。结果:两个剂量组的紫红獐牙菜对乙酰多余胆碱及组胺引起的豚鼠离体肠肌痉挛均有显著的解痉作用(P〈0.05);高剂量的紫红獐牙菜对小鼠小肠推进运动也有明显抑制作用(P〈0.05)。结论:紫红獐牙菜对动物在体及离体肠肌的收缩均有明显的抑制作用。  相似文献   

3.
目的:研究微毛诃子树皮醇提取液对小鼠的半数致死量(LD50)以及在体肠肌的影响,并且观察其对豚鼠离体肠肌的影响。方法:按Bliss法设计实验,对小鼠灌胃给药,观察5 d内小鼠的毒性反应和死亡情况,以小鼠急性死亡率为指标,测定微毛诃子提取液对小鼠的LD50;采用炭末推进实验观察药物对在体肠肌的影响;以豚鼠离体肠肌收缩幅度、张力为指标,采用离体标本运动实验法观察微毛诃子树皮醇提液对豚鼠离体肠肌的影响及其作用机制。结果:微毛诃子树皮提取液小鼠灌胃给药的LD50为5.69 g/kg,LD50的95%的可信限为4.60~7.05 g/kg;微毛诃子树皮的醇提液对小鼠在体肠肌和豚鼠离体肠肌都具有明显的舒张作用,且组胺对微毛诃子树皮的醇提液的抑制作用具有拮抗作用。结论:微毛诃子树皮的醇提取液具有一定的毒性,同时微毛诃子树皮醇提液能在一定程度上抑制肠肌的收缩,且作用机制可能与阻断组织胺受体有关。  相似文献   

4.
山苦茶对动物小肠和胆囊平滑肌的作用   总被引:5,自引:0,他引:5  
本文采用随机区组和拉丁方设计,研究山苦茶醇提物对动物小肠和胆囊平滑肌的作用,结果表明:山苦茶醇提物乳剂,对小白鼠小肠推进运动有明显的抑制作用和促进胆囊排空作用,对乙酰胆碱(Ach)、组胺、5-羟色胺(5-HT)兴奋的豚鼠离体回肠和被5-HT兴奋的豚鼠离体胆囊也均有明显的抑制作用.  相似文献   

5.
目的:观察美洲大蠊提取物CⅡ-3对豚鼠离体回肠收缩活动的影响.方法:采用离体肠肌实验,用BL-420E+生物机能实验系统记录美洲大蠊提取物CⅡ-3对乙酰胆碱(Ach)、组胺(His)及BaCl2所致离体肠肌收缩活动的影响.结果:美洲大蠊提取物CⅡ-3对Ach、His及BaCl2引起的豚鼠离体肠肌痉挛有显著的解痉作用(P<0.05).结论:美洲大蠊提取物CⅡ-3对离体肠肌的收缩具有明显抑制作用,可能与其阻断了M受体、H1受体以及阻滞了Ca2+通道有关.  相似文献   

6.
观察白酒对家兔离体小肠平滑肌活动的影响。制备家兔小肠离体肠段标本,采用常规离体灌注小肠平滑肌标本活动的实验方法,记录用药前后肠段平滑肌自发收缩性活动变化。不同度数的白酒(23°、38°、48°、56°)对小肠平滑肌自发收缩活动有抑制作用,其变化值与用药之前比较差异性显著(P<0.05,P<0.01)。最后得出结论:白酒对小肠平滑肌活动有抑制性作用。  相似文献   

7.
目的:观察毛大丁草根水煎剂对受试动物的镇咳、祛痰、平喘作用。方法:采用氨水诱咳法分别观察毛大丁草根水煎剂对小鼠咳嗽次数及咳嗽潜伏期的影响;酚红排泌法检测毛大丁草根水煎剂对小鼠呼吸道酚红排泌量的影响;离体气管法观察毛大丁草根水煎剂对乙酰胆碱(Ach)、组胺(His)诱导的豚鼠离体气管平滑肌收缩的影响。结果:毛大丁草根水煎剂可减少小鼠咳嗽次数、延长咳嗽潜伏期;可增加小鼠呼吸道酚红排泌量;可降低Ach、His诱导的豚鼠离体气管平滑肌的收缩张力。结论:毛大丁草根水煎剂对受试动物具有镇咳、祛痰、平喘作用。  相似文献   

8.
目的探讨鸡屎藤水提液促进胃肠运动功能的影响。方法采用在体肠推进性运动和胃排空实验方法以及离体肠管和胃实验方法,研究鸡屎藤水提液对肠、胃运动功能的影响。结果鸡屎藤水提液高、中、低剂量(10.0、5.0、2.5 g生药/kg)组对胃内残留率均明显降低,与蒸馏水组相比差异显著(P 0.05),对小肠推进百分比也明显提高,与蒸馏水组相比差异也显著(P 0.05);离体实验中,鸡屎藤水提液给药后的肠管平滑肌收缩的振幅显著高于给药前,与给药前相比差异显著(P 0.01),胃底环形肌的收缩频率和幅度显著高于给药前,与给药前相比差异显著(P 0.01)。结论鸡屎藤水提液具有促进肠推进性运动和胃排空的作用。  相似文献   

9.
目的:探讨月见草花浸液对豚鼠肠道平滑肌收缩活动机制。方法:豚鼠离体回肠实验法。结果:加入10%月见草花浸液1mL(浓度为3.3mg/mL),1.5mL(浓度为5.0mg/mL)时,豚鼠离体回肠收缩活动明显加强(与给药前相比较P<0.05),当加入1×10-3mol/L硫酸阿托品或1×10-4mol/L盐酸苯海拉明后,豚鼠离体回肠收缩幅度陡降,张力下降(降至正常值以下),表明硫酸阿托品竞争与M受体结合拮抗了月见草花对肠道平滑肌的作用,盐酸苯海拉明竞争与H1受体结合拮抗了月见草花对肠道平滑肌的作用。结论:月见草花兴奋肠道平滑肌可能是通过与M受体、H1受体结合而起到激动作用的。  相似文献   

10.
观察白酒对家兔离体小肠平滑肌活动的影响。制备家兔小肠离体肠段标本,采用常规离体灌注小肠平滑肌标本活动的实验方法,记录用药前后肠段平滑肌自发收缩性活动变化。不同度数的白酒(23°、38°、48°、56°)对小肠平滑肌自发收缩活动有抑制作用,其变化值与用药之前比较差异性显著(P〈0.05,P〈0.01)。最后得出结论:白酒对小肠平滑肌活动有抑制性作用。  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.
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   

14.
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   

15.
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   

16.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

17.
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   

18.
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   

19.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

20.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

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