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1.
目的:探索早期诊断和预防脑血管疾病的方法。方法:对50例高血压病Ⅲ的病人进行脑极超,脑干听[秀发电位和头部CT检查,并进行对比分析,结果:反应脑血流动力学改变的脑彩超最敏感,其次是反应脑动能改变的脑干听觉的诱发电位,而反应脑器质改变的头部CT敏感性较差,结论:脑彩超,脑干听觉诱发电位可作为早期诊断和预防脑血管病的客观指标。  相似文献   

2.
本文对普通大学生与体育系大学生脑干听觉诱发电位进行了初步的研究,结果表明:(1)人体左右两耳脑干听诱发电位各波间没有明显差异;(2)体育组峰潜伏期、波间时程(除Ⅰ、Ⅱ和Ⅲ—Ⅴ)较普通组延长,波幅较普通组增高。  相似文献   

3.
目的:探讨脑干听觉诱发电位(BAEP)的波幅问比率在糖尿病大鼠中的动态变化。方法:采用链脲佐菌素(SIZ)腹腔注射法,建立实验性糖尿病(ED)动物模型。在成模前后按时间顺序连续10周动态观测BAEP的波幅间比率的变化。结果:与正常对照组相比,ED组大鼠在病程2周时出现BAEP Ⅰ、Ⅲ、Ⅳ、Ⅴ波幅增高;在病程4周时出现BAEP各波波幅增高;病程6周时BAEP Ⅰ、Ⅱ、Ⅲ、Ⅳ波幅增高;病程8~10周时:BAEP Ⅰ、Ⅲ、Ⅳ、Ⅴ波幅增高。病程8周后BAEPⅤ/Ⅰ波幅比率下降;病程10周后BAEPⅢ与Ⅴ波幅比率降低;Ⅴ与Ⅰ、Ⅳ与Ⅰ波幅比率明显降低。结论:糖尿病大鼠BAEP的波幅和波幅比率有明显变化,这有助于糖尿病中枢神经病变的早期诊断。  相似文献   

4.
针对老年人椎-基底动脉缺血发病机理及临床表现特点,分析了年龄男60岁 ̄80岁老年人椎-基底动脉缺血82例,均起病急剧。头位改变时诱发发病率占85.40%,头痛、走路不稳占78.00%,突然眩晕不能站立并伴有恶心呕吐占5.50%,构音障碍占0.24%。均卧床何处并给予复方丹参及小剂量甘露醇静滴治疗,1d ̄3d症状减轻或全部消失。  相似文献   

5.
目的:探讨体温过低对耳蜗电图-脑干听觉诱发电位综合波(ECochG-BAEP SW)的影响。方法:体表物理降温法逐步降低豚鼠体温(36~25℃),观察脑干听觉诱发电位(BAEP)、耳蜗电图(ECochG)和ECochG—BAEPSW的波形、波峰潜伏期(PL)、波峰间潜伏期(IPL)和波幅随体温降低的变化。结果:从体温36℃到25℃,ECochG-BAEPSW波形始终兼具:BAEP和ECochG两者的特点,有十分明显突出的1波;与BAEP和ECochG一致,ECochG-BAEPSW的PL和IPL随体温降低而逐步延长;与BAEP的Ⅰ、Ⅱ、Ⅲ波和ECochG的N1、N2波波幅相似,ECochG-BAEPSW的1、2、3波波幅也在体温过低至30~29℃开始出现显著降低。结论:体温过低时ECochG-BAEP SW有BAEP和ECochG相似的显著改变,且始终兼具两者波形特点。  相似文献   

6.
本文探讨了运用MRI及TCD测定老年患者椎-基底动脉血流量并确定最低阈值及其意义。本研究测定了老年患者椎、基底动脉血流量的阈值,凡低于此阈值者与临床上诊断为椎-基底动脉缺血具有较高的符合率。因此,此方法有助于椎-基底动脉缺血评估。  相似文献   

7.
目的:探讨脑干听觉诱发电位(BAEP)检查用于高血脂的诊断价值。方法:对76例高血脂病例和54例血脂正常者进行BAEP检查进行比对。结果:高血脂组与对照组BAEP测定的潜伏期(PL)和波间期(IPL)均检出异常。结论:血脂增高对听力障碍有很大影响。BAEP检查对该病有一定的诊断价值。  相似文献   

8.
不同月龄Beagle犬的心电图研究   总被引:1,自引:0,他引:1  
对不同月龄的66只健康Beagle犬采用3%戊巴比妥钠麻醉,进行了9个导联的心电图描记和分析。结果表明:健康Beagle犬为窦性心律:30月龄以下育成犬心律平均为173.8次/分,种用犬(50月龄以上)心率平均为131.7次/分;二者经统计学处理,有极显著差异。P波间期平均为0.051±0.013Sec。P波振幅平均0.061mv,P波直立在导联中占92.6%,在aVR导联中P波倒置率98.75%;QRS波间期均值为:0.027±0.005Sec。在Ⅱ导联中范围为0.02-0.04S-ec。在各导联中,Ⅰ导联以r波为主(51.85%),Ⅱ导联以Rs波多见(50%),Qr波和qr波在aVR导联中出现较多(38.89%,31.48%)。T波在Ⅰ、Ⅱ、Ⅲ、avF、Ⅴ1、Ⅴ2、Ⅴ3导联中直立为主,在avL导联中倒置多见(89.2%,73.1%)。T波方向与QRS波一致。T波振幅平沟0.137mv。P-R间期范围在此0。075-0.140Sec。在9个导联中,无明显S-P段偏移。P-P间隔<0.01Sec。  相似文献   

9.
总结了542例孕33 ̄44周孕妇的胎儿脐动脉血流速度波型图的S/D值,并对分娩后新生儿体重、有否脐带缠绕及胎儿宫内窘迫等进行比较。结果:155例正常足月妊娠产妇其S/D值〈3.0。25例S/D值≥3.0均为高危妊娠。S/D值异常对胎儿宫内发育迟缓(IUGR)的阳性预测率为32.0%;对胎儿宫内窘迫的阳性预测率为68.0%,而脐带缠绕其S/D值则在正常或偏低范围。资料显示胎儿脐动脉血流速度波型图  相似文献   

10.
120例聋哑儿240耳的脑干电反应测听结果234耳(97.5%)有残余听力,216耳(88.3%)听阈高于110dB,平均听阈为83.7dB,在100dB可诱出波Ⅰ、Ⅲ、Ⅴ者共180耳,达75%,波形变异及波Ⅴ波幅低于0.15μV者占18%;因此大部分聋哑儿具备语言训练的条件。  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.
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   

13.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

14.
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   

15.
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   

16.
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   

17.
18.
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   

19.
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   

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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