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21.
胸腰脊神经后根形态计量研究   总被引:4,自引:1,他引:4  
在15具成人尸体上对胸腰脊神经后根进行了大体解剖和形态计量研究.结果表明:(1)上胸段脊神经后根的囊外段长度、硬膜点横径和脊髓点束数在逐节减少;后根的囊外段与囊长轴之下夹角>90°,囊内段及脊髓点分布长度在逐节增加,交通支最丰富.(2)中胸段脊神经后根的囊外段长度、硬膜点横径和脊髓点束数各节段波动范围较小,下夹角在90°左右,囊内段短,脊髓点分布长.(3)下胸段脊神经后根的脊髓点分布长度转而下降,下夹角<90°,其它指标均逐节增加.(4)腰段脊神经后根的脊髓点分布长度进一步减少,下夹角最小,其它指标达最大值,交通支丰富.根据研究结果进行后根受损危险排序,腰>下胸>上胸>中胸.  相似文献   
22.
The long-term ST database is the result of a multinational research effort. The goal was to develop a challenging and realistic research resource for development and evaluation of automated systems to detect transient ST segment changes in electrocardiograms and for supporting basic research into the mechanisms and dynamics of transient myocardial ischaemia. Twenty-four hour ambulatory ECG records were selected from routine clinical practice settings in the USA and Europe, between 1994 and 2000, on the basic of occurrence of ischaemic and non-ischaemic ST segment changes. Human expert annotators used newly developed annotation protocols and a specially developed interactive graphic editor tool (Semia) that supported paperless editing of annotations and facilitated international co-operation via the Internet. The database contains 86 two- and three-channel 24h annotated ambulatory records from 80 patients and is stored on DVD-ROMs. The database annotation files contain ST segment annotations of transient ischaemic (1155) and heart-rate related ST episodes and annotations of non-ischaemic ST segment events related to postural changes and conduction abnormalities. The database is intended to complement the European Society of Cardiology ST-T database and the MIT-BIH and AHA arrhythmia databases. It provides a comprehensive representation of ‘real-world’ data, with numerous examples of transient ischaemic and non-ischaemic ST segment changes, arrhythmias, conduction abnormalities, axis shifts, noise and artifacts.  相似文献   
23.
The nucleotide sequence of RNA segment 3 of A/FPV/Rostock/34 (H7N1), an avian strain of influenza A virus, has been determined from a cloned DNA copy. Segment 3 codes for the PA polypeptide and the sequence specifies an acidic polypeptide of 716 amino acid residues. Comparison of the sequence with the corresponding segment of two human strains A/PR/8/34 and A/NT/60/68 indicates significant divergence of the avian sequence from the human sequences at the nucleotide level. At the amino acid level there is considerably greater homology between the avian and human strains. This presumably reflects a constraint on divergence of the PA polypeptide imposed by a common functional requirement of PA in all influenza virus strains.  相似文献   
24.
胰腺外科学分段的解剖学基础及其意义   总被引:1,自引:0,他引:1  
目的:为胰腺外科学分段提供解剖学基础。方法:在64具灌注标本和4具铸型标本上观察胰内动脉分布、吻合。结果:头由胰十二指肠上动脉和胰十二指肠下动脉供血;颈为一乏血管区;体和尾由胰背动脉、胰支、胰大动脉和胰尾动脉供血。结论:全部胰腺可分为左侧段和右侧段  相似文献   
25.
Summary There have been a number of attempts in the last years to localize the generators of brain electromagnetic activity, considering one current dipole as the source model. Single Dipole Localization (SDL) requires the selection of an optimization algorithm (OA). General aspects related with the selection, implementation and evaluation of some of the OA employed for SDL are discussed in this paper. Specifically the performance of two algorithms, those of Hooke-Jeeves and Levenberg-Marquardt, are tested by simulations. Suggestions for including restrictions to the dipole position and comments about some commonly used measures of the goodness of fit are given. Examples of erroneous implementations of these algorithms are also illustrated. A simple graphic rejection criterion, which can be easily used by inexperienced researchers, is introduced and tested in noisy and noise free simulations.The authors are grateful to Roberto D. Pascual Marqui for programming the Hooke-Jeeves algorithm.  相似文献   
26.
夏豪  胡波  周桃  谭安安 《微循环学杂志》2007,17(3):48-49,52
目的:观察盐酸替罗非班对平板运动试验中ST段抬高患者TIMI血流分级的影响。方法:将平板运动试验ST段抬高患者35例按就诊顺序随机双盲分为受试组(n=18)和对照组(n=17),受试组在对照组给予阿司匹林、氯吡格雷、肝素等基础治疗上加用盐酸替罗非班,所有患者疗程结束后均行选择性冠状动脉血管造影(SCA)检查,观察两组患者治疗后TIMI血流情况。结果:与对照组相比,受试组应用盐酸替罗非班后TIMI血流分级提高,达2级血流者比例高于对照组(44.44%比11.76%,P<0.05);受试组完全闭塞者比例明显低于对照组(5.56%比35.29%,P<0.05)。结论:盐酸替罗非班可以改善平板运动试验中ST段抬高患者TIMI血流分级。  相似文献   
27.
The etiology of the juvenile type of the human ceroid-lipofuscinosis (JCL) is unknown, in spite of the fact that the first report of this disease was given more than 160 years ago. The necessity of good animal models for scientific progress in chronic metabolic diseases in humans is obvious. The inbred strain of English setter with ceroid-lipofuscinosis (CCL) seems to be a perfect model for human JCL. Dogs with CCL and organs for research purposes are available from Dr. Koppang's experimental kennel in Norway.  相似文献   
28.
This paper presents a mathematical model of blood volume kinetics and renal function in response to burn injury and resuscitation, which is applicable to the development and non-clinical testing of burn resuscitation protocols and algorithms. Prior mathematical models of burn injury and resuscitation are not ideally suited to such applications due to their limited credibility in predicting blood volume and urinary output observed in wide-ranging burn patients as well as in incorporating contemporary knowledge of burn pathophysiology. Our mathematical model consists of an established multi-compartmental model of blood volume kinetics, a hybrid mechanistic-phenomenological model of renal function, and novel lumped-parameter models of burn-induced perturbations in volume kinetics and renal function equipped with contemporary knowledge on burn-related physiology and pathophysiology. Using the dataset collected from 16 sheep, we showed that our mathematical model can be characterized with physiologically plausible parameter values to accurately predict blood volume kinetic and renal function responses to burn injury and resuscitation on an individual basis against a wide range of pathophysiological variability. Pending validation in humans, our mathematical model may serve as an effective basis for in-depth understanding of complex burn-induced volume kinetic and renal function responses as well as development and non-clinical testing of burn resuscitation protocols and algorithms.  相似文献   
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