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31.
Castellote JM Valls-Solé J Sanegre MT 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2004,158(1):35-42
In preparation for performing task specific ballistic movements, subjects may choose among different possibilities for setting up their motor apparatus, ranging from quiet resting to different types of muscle activation. In the study presented here, we investigated whether differences in the motor set modify either the reaction time or the kinematic characteristics of the movement. Subjects wearing surface EMG recording electrodes in the wrist extensor (WE) and wrist flexor (WF) muscles were requested to react to the presentation of a visual stimulus by performing a ballistic wrist extension movement of an amplitude of about 50° in the following experimental conditions: resting quietly, which was considered as the control condition (CC); isometric contraction (IC), in which subjects were required to activate WE and WF muscles isometrically; rapid oscillations (RO), in which subjects were requested to make a fast oscillatory wrist movement; and slow oscillations (SO), in which subjects were maintaining a slow oscillatory motion of the wrist. To constrain the movement to the wrist joint and limit the action of postural muscles, the subjects forearm and hand were attached to joined non-resistive metallic platforms, allowing for free non-frictional displacement. In the EMG recordings, we measured the size of the EMG bursts in agonist and antagonist muscles, and the inter-burst intervals. In movement recordings, we measured movement onset latency and the velocity profile. Movement onset was delayed in SO with respect to all other conditions. Conversely, peak velocity was larger in all test conditions in comparison to CC. There were no differences in the size of the first EMG burst of the agonist muscle, but significant changes occurred in the subsequent bursts recorded in the agonist and antagonist muscles. Our study indicates that the motor program used to execute a ballistic voluntary movement is influenced by the conditions of the motor system. The configuration of the motor set should be specifically considered in the search for improving the speed of the reaction and the kinematics of ballistic movements.JMC and MTS were funded by the Spanish Ministry of Education, Culture and Sport, with grant numbers PR 2003-0212 and AP2000-0913 相似文献
32.
Two groups of pigeons with a history of two choice operant drug discrimination tasks (3.0 mg/kg morphine versus 5.6 mg/kg cocaine, and 3.0 mg/kg morphine versus 3.0 mg/kg cocaine, respectively; Swedberg and Järbe 1985) were subjected to three choice tasks in which responses on a third manipulandum were reinforced in the no drug condition. Training drugs generalization gradients in both groups were similar to those normally obtained in two choice drug versus no drug tasks. The salience differences between the training stimuli within the groups observed in the previous two choice task did not differentially affect the three choice discrimination gradients. Tests with novel drugs after the introduction of the no drug condition yielded increased responding to the no drug condition with the exception of the dopamine agonist apomorphine. Results are discussed in terms of a discrimination learning model specifying principles of relative discriminative stimulus control in various discrimination cases.Portions of these data were presented at the International Union of Pharmacology, IUPHAR, 9th International Congress of Pharmacology Satellite Meeting: European Study Group for Internal Stimulus Control by Electrical Stimulation, Drugs and Other Means, ESISC, London, July 29–August 3, 1984 (Swedberg and Järbe 1984). An earlier version of this work appears in the doctoral thesis by the first author (Swedberg 1985). 相似文献
33.
“三公经费”是我国事业单位经费中一项主要组成部分,医院作为事业单位,“三公经费”的管理也尤为重要。目前,我国医院的“三公管理”尚且存在一些问题有待解决,该文先就目前三公经费现状与不足三公经费问题成因分析进行简单概述,再对加强医院三公经费管理的对策进行进一步分析。 相似文献
34.
目的探讨中孕期胎儿染色体异常(FCA)高危孕妇羊水细胞胎儿染色体核型(FK)及其介入性产前诊断(IPD)指征。方法选择2014—2018年,在四川大学华西第二医院产前诊断中心进行羊膜腔穿刺术羊水细胞FK检测的63581例FCA高危孕妇(孕龄为19~27+6孕周)为研究对象。回顾性分析孕妇不同IPD指征及其胎儿染色体核型异常(FKA)检测结果。本研究遵循的程序符合四川大学华西第二医院伦理委员会所制定的伦理学标准,并通过该伦理委员会批准[审批文号:医学科研2019伦审批第(077)号]。结果①本组63581例中孕期孕妇的FKA检出率为3.13%(1989/63581)。这63581例孕妇的IPD指征分别为高龄(预产期年龄≥35岁)(25648例)、血清学筛查高风险(29009例)、无创产前筛查(NIPT)高风险(333例)、夫妇一方为染色体异常携带者(603例)、超声筛查发现胎儿结构异常及超声软指标异常(2647例)、异常儿生育史(1546例)、于外院进行羊水细胞FK分析结果异常者(7例)、孕妇智力低下及合并智力低下家族史(149例)、孕妇早孕期有害物质接触史(1400例)、其他(2239例),FKA检出率分别为3.26%(836/25648)、2.04%(593/29009)、65.17%(217/333)、34.33%(207/603)、3.51%(93/2647)、1.68%(26/1546)、85.71%(6/7)、4.03%(6/149)、0.14%(2/1400)、0.13%(3/2239)。②351例孕妇的IPD指征为超声筛查发现胎儿结构异常中,IPD指征为胎儿淋巴水囊瘤、皮肤水肿的FKA检出率最高,为26.09%(6/23)。2296例孕妇的IPD指征为胎儿超声软指标异常中,IPD指征为胎儿颈项透明层(NT)值≥2.5 mm的FKA检出率最高,为7.74%(66/853)。结论孕妇高龄、血清学筛查高风险、NIPT高风险、夫妇一方为染色体异常携带者、超声筛查发现胎儿结构异常及超声软指标异常等,均为中孕期孕妇FCA的IPD指征,孕妇IPD指征类型不同,FCA风险不同。羊膜腔穿刺术羊水细胞FK检测,可预测有IPD指征孕妇的妊娠结局,为降低FKA出生率提供参考。 相似文献
35.
螺旋CT三维成像对颌面部骨折的诊断价值 总被引:1,自引:0,他引:1
目的 探讨螺旋 CT三维成像对于颌面部骨折的诊断价值。方法 对 2 5例颌面部外伤患者进行螺旋 CT薄层扫描和三维重建成像。结果 螺旋 CT三维成像能够立体地显示骨折的位置、形态、范围和类型。结论螺旋 CT三维成像对于显示颌面部骨折的空间关系具有重要的诊断价值 相似文献
36.
37.
《Asian journal of surgery / Asian Surgical Association》2021,44(12):1515-1519
BackgroundPolypoid lesion of gallbladder (PLG) size larger than 10 mm is considered to be one of the surgical indications, but the final pathological results are mostly non-neoplastic polyps. The aim of the study was to define the risk factors to discriminate neoplastic PLG and create more precise criteria for surgical indications.MethodsA large scale, case-series study based on 2704 patients who underwent cholecystectomy for PLG was designed. Logistic regression analysis and receiver operating characteristic curve (ROC) was adopted to identify risk factors and the optimal size criteria for predicting neoplastic PLG.ResultsPatients in the neoplastic group were significantly older than those in the non-neoplastic group and the average PLG size is much larger in the neoplastic group (18.5 ± 4.7 mm vs 12.6 ± 3.6 mm). Neoplastic PLGs are prone to be single and non-neoplastic polyps are usually multiple. On Multivariate logistic regression analysis, PLG size larger than 15 mm and age older than 43 years were found to be the independent risk factors to discriminate neoplastic PLG (Odds ratio 3.546 and 2.77 respectively). The ROC curve showed that 12 mm might be the more reasonable PLG size threshold for the surgical suggestion.ConclusionsConsidering its moderate diagnostic accuracy, the size of gallbladder polyp larger than 10 mm is insufficient to indicate surgical therapy for PLG and 12 mm should be the more optimal polyp's size threshold. Patients older than 43 years have a higher risk of having neoplastic polyps. 相似文献
38.
Jo-Lynn S. Tan Niranjan Sathianathen Marcus Cumberbatch Prokar Dasgupta Alexandre Mottrie Ronney Abaza Koon Ho Rha Thyavihally B. Yuvaraja Dipen J. Parekh Umberto Capitanio Rajesh Ahlawat Sudhir Rawal Nicolò M. Buffi Ananthakrishnan Sivaraman Kris K. Maes Gagan Gautam Francesco Porpiglia Levent Turkeri Mahendra Bhandari Benjamin Challacombe James Roscoe Porter Craig R. Rogers Daniel A. Moon 《BJU international》2021,128(Z3):30-35
39.
Distal rectus femoris surgery in children with cerebral palsy: results of a Delphi consensus project
Robert M. Kay Kristan Pierz James McCarthy H. Kerr Graham Henry Chambers Jon R. Davids Unni Narayanan Tom F. Novacheck Jason Rhodes Erich Rutz Jeffrey Shilt Benjamin J. Shore Matthew Veerkamp M. Wade Shrader Tim Theologis Anja Van Campenhout Thomas Dreher 《Journal of children's orthopaedics》2021,15(3):270
PurposeThe purpose of this study was for an international panel of experts to establish consensus indications for distal rectus femoris surgery in children with cerebral palsy (CP) using a modified Delphi method.MethodsThe panel used a five-level Likert scale to record agreement or disagreement with 33 statements regarding distal rectus femoris surgery. The panel responded to statements regarding general characteristics, clinical indications, computerized gait data, intraoperative techniques and outcome measures. Consensus was defined as at least 80% of responses being in the highest or lowest two of the five Likert ratings, and general agreement as 60% to 79% falling into the highest or lowest two ratings. There was no agreement if neither threshold was reached.ResultsConsensus or general agreement was reached for 17 of 33 statements (52%). There was general consensus that distal rectus femoris surgery is better for stiff knee gait than is proximal rectus femoris release. There was no consensus about whether the results of distal rectus femoris release were comparable to those following distal rectus femoris transfer. Gross Motor Function Classification System (GMFCS) level was an important factor for the panel, with the best outcomes expected in children functioning at GMFCS levels I and II. The panel also reached consensus that they do distal rectus femoris surgery less frequently than earlier in their careers, in large part reflecting the narrowing of indications for this surgery over the last decade.ConclusionThis study can help paediatric orthopaedic surgeons optimize decision-making for, and outcomes of, distal rectus femoris surgery in children with CP.Level of evidenceV 相似文献
40.
右肺支气管树的三维分形模拟 总被引:2,自引:0,他引:2
肺是天然的非对称不规则体。肺内的气管树呈复杂的自相似的结构。基于最小能耗思想 ,作者根据肺的解剖学数据 ,建立右肺的细分网格坐标 ,通过计算各级分块的质心 ,寻找分叉方向与确定分叉长度 ,以 Open GL 为工具 ,实现了右肺支气管树的三维分形模拟 ,并且得到各级的长度、分叉角度和管径的具体参数。所生成的图形在形态与几何参数上与现有统计数据很吻合。计算得到该模型的分形覆盖维数为 2 .19,与其他学者计算的人体肺的理想维数 2 .17[1 ] 比较接近。该模型为今后用分形思想研究肺的气体扩散传递功能奠定基础。从节省计算机存储、加快图形传输上方面来说也有一定意义 相似文献