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1.
采用常规方法剥离制备神经-腓肠肌标本,分别用浸有0.5%、1%和1.5%催产素的纱布浸润标本,浸润5min后,测量蟾蜍坐骨神经-腓肠肌的阈强度(mv)、收缩幅度(g)以及收缩潜伏期(ms),与放入正常任氏液作比较。经0.5%的催产素浸润后,腓肠肌的阈强度无明显变化,收缩幅度增大,且潜伏期时间缩短;经1%的催产素浸润后,腓肠肌的阈强度减小,收缩幅度增大,潜伏期时间相应缩短;而经1.5%浓度的催产素浸润后,腓肠肌的阈强度、收缩幅度以及潜伏期均无明显变化。较低浓度催产素可以提高骨骼肌收缩的兴奋性,但受药物剂量的限制。超过一定范围,骨骼肌收缩不随催产素浓度变化或随浓度增加骨骼肌的收缩能力相应减弱。  相似文献   

2.
采用“先离体法”和“后离体法”两种方法制备蛙坐骨神经-腓肠肌标本,通过实验记录,对标本的收缩机能进行了比较.结果表明后离体法制备的标本单收缩幅度高,潜伏期和舒张期时程缩短,并对其原因进行了分析与讨论.  相似文献   

3.
通过对牛蛙腓肠肌收缩性的研究,将接受连续刺激产生疲劳后的腓肠肌浸泡在不同浓度的ATP中,利用LMS-2B型二道生理纪录仪记录腓肠肌在不同ATP浓度中消除疲劳后的收缩强度和疲劳时间,观察不同浓度的ATP(2%、3%、4%)对接受连续刺激产生疲劳后的腓肠肌收缩能力的影响.实验结果显示:使牛蛙腓肠肌收缩能力最佳的ATP浓度为3%.  相似文献   

4.
不同训练强度和训练量后大鼠骨骼肌HSP72的表达   总被引:1,自引:0,他引:1  
为探讨不同训练强度和不同训练量后大鼠不同类型骨骼肌运动适应能力与热休克蛋白表达的变化.采用44只雄性2月龄大鼠随机分成5组:对照组(n=8),中强度组(n=8),大强度组(n=10),中运动量组(n=8)和大运动量组(n=10),在训练8周后处死取材并测定其血清肌酸激酶浓度及同侧比目鱼肌、红色腓肠肌和白色腓肠肌湿质量和HSP72蛋白含量.结果表明:(1)各训练组大鼠8周后血清肌酸激酶浓度显著高于对照组,尤以大强度组为高.(2)不同强度和负荷训练后都能导致大鼠骨骼肌湿质量出现一定的变化,但大负荷组相关指标出现显著异常.(3)大运动量组HSP72表达显著高于对照组、中等强度和大强度训练组.大强度和大运动量都能引起HSP72在腓肠肌的过高表达,尤以在红色腓肠肌中表达为高,这实际上是一种骨骼肌自我保护机制的表现.不同类型骨骼肌HSP72异常表达变化早于骨骼肌运动适应能力的变化,提示骨骼肌运动适应能力与其HSP72表达变化可能有关.  相似文献   

5.
bFGF对大鼠坐骨神经损伤后腓肠功能恢复的影响   总被引:2,自引:0,他引:2  
目的:观察碱性成纤维细胞生长因子(bFGF)对大鼠坐骨神经损伤后腓肠肌功能恢复的方法:以钳夹损伤左侧坐骨神经大鼠为模型,治疗组肌肉注射bFGF,对照组注射等渗盐水,隔日1次。术后2、3、4周分别对治疗且和对照组损伤仙侧腓肠肌进行肌诱发电位及肌收缩力检测,以健侧为100%,求出损伤侧各指标的恢复率。结果:与对照组相比,治疗组腓肠肌诱发电位幅值恢复率明显加快;腓肠肌单收缩力和强直收缩力的恢复率也显著加  相似文献   

6.
三种麻醉剂对离体骨骼肌收缩性影响的比较研究   总被引:4,自引:0,他引:4  
目的:探讨三种不同的麻醉剂对蟾蜍离体腓肠肌收缩性的影响.方法:把剥制好的离体腓肠肌标本先浸泡在任氏液中,用BL-410生物机能实验系统记录最适刺激下的单收缩曲线;然后换上不同浓度的麻醉剂浸泡8min,记录单收缩曲线.分别测定单收缩的最大收缩力、收缩速率、舒张速率、抑制率.结果:三种不同的麻醉剂对蟾蜍离体腓肠肌收缩能力均有不同程度的抑制作用,低浓度下氨基甲酸乙酯的抑制作用最强,其次是水合氯醛,戊巴比妥钠的抑制作用最小.中、高浓度下水合氯醛的抑制作用最强,其次是氨綦甲酸乙酯,戊巴比妥钠的抑制作用最小.  相似文献   

7.
研究了中华猕猴桃蛋白酶在不同浓度(V:V)乙醇存在下的内源荧光发射光谱、紫外差光谱、圆二色光谱(CD谱)及傅立叶变换红外光谱的变化,并测定了相应的活力变化,当乙醇浓度低于30%时,酶的荧光强度无明显变化,而乙醇浓度大于30%时,则酶荧光强度增大,且峰位略红移。在乙醇溶液中,酶的紫外差光谱在225~235nm内出现正峰,峰强度随乙醇浓度的增高基本表现为逐渐增大,峰位也逐渐蓝移。CD谱及红外光谱的测定结果表明低浓度乙醇中酶分子有序二级结构的减少及高浓度乙醇中β-折叠含量的增加.随乙醇浓度的增加.酶的活力表现为逐渐降低,且乙醇对酶的失活作用类似于竞争性抑制。  相似文献   

8.
目的研究中等强度跑台运动训练对雄性SD大鼠腓肠肌结构及及最大收缩张力的影响。方法以60只雄性SD大鼠为实验对象,将其随机分为对照组和运动运动训练组。运动训练组大鼠进行连续4~6周中等强度的跑台运动运动训练,用张力传感器观察运动训练后腓肠肌等长收缩最大张力变化,用反转录聚合酶链式反应测量腓肠肌MHC mRNA含量,用免疫组化方法检测肌纤维中肌球蛋白的改变,镜下测量腓肠肌横截面积的大小。结果①连续4~6周跑台运动训练后,肌纤维MHCⅡx,MHCⅡb mRNA含量较安静对照组有显著性差异(P<0.05)和(P<0.01),而MHCⅡb和MHCⅠmRNA变化不明显。②运动训练后肌球蛋白转变为以Ⅰ型慢肌纤维为主,同时肌纤维横截面积增大。③方脉冲电刺激诱发6周运动训练组大鼠腓肠肌等长收缩最大张力较对照组显著增加(P<0.01)。结论中等强度运动训练可促进骨骼肌纤维的转型与骨骼肌重塑。  相似文献   

9.
bFGF对大鼠坐骨神经损伤后腓肠肌功能恢复的影响   总被引:1,自引:0,他引:1  
目的:观察碱性成纤维细胞生长因子(b F G F) 对大鼠坐骨神经损伤后腓肠肌功能恢复的作用。方法:以钳夹损伤左侧坐骨神经大鼠为模型,治疗组肌肉注射b F G F,对照组注射等渗盐水,隔日1 次。术后2 、3 、4 周分别对治疗组和对照组损伤侧及健侧腓肠肌进行肌诱发电位及肌收缩力检测,以健侧为100 % ,求出损伤侧各指标的恢复率。结果:与对照组相比,治疗组腓肠肌诱发电位幅值恢复率明显加快( P< 005) ;腓肠肌单收缩力和强直收缩力的恢复率也显著加强( P< 005 和 P< 001) 。结论:b F G F 能促进大鼠坐骨神经损伤后骨骼肌运动功能的恢复  相似文献   

10.
 为研究在生后不同年龄组家兔外侧腓肠肌各亚体肌纤维MyHCs变化与诱发电位的关系,探讨生后发育期间肌纤维MyHCs组成和作用差异与表型之间的相关联系,采用电生理记录仪结合十二烷基硫酸钠-聚丙烯酰胺凝胶电泳(SDS PAGE)检测外侧腓肠肌各亚体。结果表明中间亚体在刺激时各年龄组的峰值电压基本相同,而外侧亚体和内侧亚体分别有些变化。同时发现成年家兔的持续时间都较幼年的长,这可能与各亚体的肌纤维型构成比例有很大关系。外侧腓肠肌各亚体的肌球蛋白重链异构体(MyHCs)电泳条带分别显示MyHCsⅡa、Ⅱd(或Ⅱx)、Ⅱb、Ⅰ共4种,对应于骨骼肌纤维表型ⅡA型(FOG型)、ⅡX(FO型)、ⅡB型(FG型)及Ⅰ型(SO型)4类。  相似文献   

11.
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   

12.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

13.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

14.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

15.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

16.
17.
The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.  相似文献   

18.
R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).  相似文献   

19.
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   

20.
The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.  相似文献   

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