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1.
被动体位倾斜时的心血管反应为了了解重力对心血管调节功能的影响,本实验观察了12名健康男性被试者在重力作用逐渐增加时的心血管反应。实验中采用了逐渐改变被试者倾斜方向和角度的方法,造成对心血管系统的不同刺激,即采用了立位15°、30°、60°及头低位-1...  相似文献   

2.
立位-下体负压时心血管指标的变化   总被引:4,自引:3,他引:1  
目的了解立位 -下体负压 (HUT +LBNP)期间心血管系统的变化 ,确定心律变异和脉图两种方法在评价心血管调节功能中的作用。方法观察 1 6名被试者在 75°头高位倾斜加 - 4kPa下体负压 2 0min期间血压、脉图、心律变异和脑血氧饱和度的变化。结果 ( 1 )HUT +LBNP可引起被试者出现明显的心率、血压、规 -化低频峰功率 (LFn)、LFn/HFn增加 ,脑血氧饱和度、心电T波和规 -化高频峰功率(HFn)下降 ;( 2 )晕厥前出现明显的血压、心率和脑血氧饱和度下降 ;( 3)低耐力组在HUT +LBNP初期的心率明显高于高耐力组 ;( 4 )HUT +LBNP时脉搏波波形发生很大变化 ,无法进行分析。结论HUT +LBNP是一种负荷量较高的立位耐力检查方法 ,可充分暴露被检者在立位中的心血管调节功能 ;脉图检测方法不能作为评价被试者HUT +LBNP耐力的方法。  相似文献   

3.
头低位卧床7d对立位心肺循环功能的影响   总被引:6,自引:1,他引:5  
目的观察短期模拟失重对立位心肺循环功能的影响,为进一步研究失重时心血管功能下降机理积累资料。方法6名健康男性被试者,头低位6°卧床7d。分别观察卧床前、后立位心肺循环功能的变化。心肺循环功能检测选用XXH-2000型小循环心功能检测仪。结果头低位卧床7d致被试者立位耐力降低,卧床后右心室射血期(j-z)缩短,右心室排血效率降低(Q-j/j-z升高),提示右心功能减退。心血管调节适应性反应减弱,右心功能储备降低。结论c波高度(hc)、c波高度与Z波高度的比值(hc/hz)可作为评价立位耐力或预测立位晕厥的指标;小循环心功能检测法评价立位心肺循环功能的变化有一定的前景。  相似文献   

4.
立位负荷量增加时压力感受器反射功能的变化   总被引:2,自引:1,他引:1  
为了了解立位负荷量增加和中枢对压力感受器反射功能的影响,本实验观察了8名被试者在两种不同方式(加心算和无心算)的递增性负压—立位负荷时(下身负压值为0、2.67、5.33、8.00kPa)BRF的变化。结果表明压力感受器反射增益随着立位负荷量的增加而增加,但在极限负荷时增益下降,反射功能的降低是造成立位晕厥的主要原因。立位中加心算后,反射增益和负荷量的关系不密切,说明中枢兴奋对立位时压力感受器的反射功能有抑制作用。  相似文献   

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观察了12名被试者在下体负压作用下脑氧饱和度(SrO2)的变化,并作了分析。结果表明:(1)下体负压作用下,SrO2呈现显著下降的趋势;(2)在负压终止的时刻,不同状态组之间SrO2的变化量差别显著;(3)下体负压作用下SaO2保持不变,SrO2的改变与眶上动脉血流改变的百分数显著相关(r=0.59~0.86,P<0.05或0.01)。以上结果提示下体负压作用下SrO2的改变与脑血流的下降有关,而且用SrO2探测晕厥前状态及晕厥是可能的。作者据此推测SrO2的监测能够在G-LOC的研究中得到应用。  相似文献   

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目的观察头低位后直立位下体负压暴露的耐力和心血管反应。方法8名被试者在下体负压倾斜床上进行“直立位-倒立位30s-直立位联合下体负压(-60mmHg)致晕厥前症状”的模拟推拉效应试验及单纯直立位 下体负压(-60mmHg)致晕厥前症状的对照试验,用阻抗法测量了试验过程中心血管功能指标的变化。结果在模拟推拉效应试验中,8名被试者出现晕厥前症状的平均耐受时间为4.5±2.4min,显著低于对照试验时的8.4±2.1min(P<0.01)。在倒立位,被试者HR较直立位基础值降低,SV和CO较直立位基础值升高,均有显著性意义。和基础值相比,直立位下体负压时HR增加的百分比显著低于对照试验(P<0.05),而直立位下体负压时SV和CO降低的百分比均显著高于对照试验时SV和CO降低的百分比(P<0.05)。在直立位下体负压暴露时,对照试验的PP和基础值比较显著降低(P<0.05),TPR比基础值显著增加(P<0.05)。结论倒立位后,再进行直立位下体负压作用,出现晕厥前症状的平均耐受时间缩短,心血管反应降低。  相似文献   

7.
有空中晕厥史飞行员微循环的特征及其可能的影响   总被引:2,自引:1,他引:1  
目的 探讨微循环与空中晕厥发生的关系。方法试验对象为39名有空中晕厥文的飞行员并设对照健康组飞行员46人。两组飞行员均作常规主动立位耐力试验,试验前后测量血压、心率和微循环各项指标。结果 两组立位耐力试验后,晕厥组多项指标与对照组差异明显,特别是管拌数目、心率、收缩压、血管长度、拌顶宽度、输入枝、输出枝直径等(P<0.05)。而多数变化从立位即刻开始至立位后20min持续加深而血压进一步下降。结论 微循环的变化与易发空中晕厥有关系,改善微循环对预防和矫治空中晕厥可能有意义。  相似文献   

8.
目的观察模拟失重条件对人体左心舒张功能的影响 ,探讨其在航天后心血管功能失调中的作用。方法采用超声多谱勒技术观察了 6名健康青年男性在 2 1d - 6°头低卧位模拟失重前、实验第 1 0、2 1天及实验后左心舒张功能变化 ,同时检查其卧床前后的立位耐力改变。结果被试者左心舒张功能指标 :经二尖瓣血流E峰最大流速 (PEV)、A峰最大流速 (PAV)、E峰血流速度积分 (VTIE)指标在实验第1 0、2 1天均较实验前有明显的降低 (P <0 .0 5 ) ;而A峰血流速度积分 (VTIA) ,峰值血流速度比值 (A/E)及血流速度积分比值 (VTIA/E)的下降则未达到显著水平 (P >0 .0 5 )。 6名被试者均未能通过立位耐力检查。结论模拟失重可引起人体左心舒张功能的显著下降  相似文献   

9.
航天飞行后立位耐力不良严重影响航天员返回地面的适应能力。中医的整体理论适合航天医学问题研究。准确认识飞行后立位耐力不良的病因病机,能做到辨证论治,做好针对性干预。综合分析了航天飞行后立位耐力不良的中医病因病机,总结得出航天飞行后立位耐力不良的中医病因包括重力变化、节律变化、性别差异、航天器特殊生活环境的变化、心理因素、饮食因素等6个方面,中医病机为脏腑功能紊乱,调整适应能力下降,以及气血不足,清阳不升和血供动力不足。同时综述了中医对抗飞行后立位耐力不良措施的研究进展,对中医药及针灸在防治航天飞行后立位耐力不良中的应用进行了展望。  相似文献   

10.
目的 研制基于小型一体化生物电阻抗电极的用于多部位阻抗血流图检测的仪器,用于检测手腕、颈、脑等多部位阻抗血流图和评价运动负荷状态下组织中阻抗血流图的变化。方法 采用高共模抑制比的差动放大器和相关检测原理对小型电极提取的微弱信号进行处理,设计相应的电路,提高信噪比,实现阻抗血流小型传感器微弱信号的检测。结果 经过实验验证,该仪器能够提取手腕、颈、脑等部位的阻抗血流信号,应用相干检测技术得到了很高的信噪比,测量方便,可以进行连续监测。结论 该仪器能够检测人体不同部位阻抗血流信号的搏动分量和非搏动性的直流分量,更好地评价局部血液循环状况,并且有望对运动负荷状态下的阻抗血流动力学参数作出评价。  相似文献   

11.
The Knee injury and Osteoarthritis Outcome Score (KOOS) is a self-administered instrument measuring outcome after knee injury at impairment, disability, and handicap level in five subscales. Reliability, validity, and responsiveness of a Swedish version was assessed in 142 patients who underwent arthroscopy because of injury to the menisci, anterior cruciate ligament, or cartilage of the knee. The clinimetric properties were found to be good and comparable to the American version of the KOOS. Comparison to the Short Form-36 and the Lysholm knee scoring scale revealed expected correlations and construct validity. Item by item, symptoms and functional limitations were compared between diagnostic groups. High responsiveness was found three months after arthroscopic partial meniscectomy for all subscales but Activities of Daily Living.  相似文献   

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Objective To investigate endovascular treatment of traumatic direct carotid-cavernous fistulas (CCF) and their complications such as pseudoaneurysms. Methods: Over a five-year period, 22 patients with traumatic direct CCFs were treated endovascularly in our institution. Thirteen patients were treated once with the result of CCF occluded, 8 twice and 1 three times. Treatment modalities included balloon occlusion of the CCF, sacrifice of the ipsilateral internal carotid artery with detachable balloon, coll embolization of the cavernous sinus and secondary pseudoaneurysms, and covered-stem management of the pseudoaneurysms. Results All the direct CCFs were successfully managed endovascularly. Four patients developed a pseudoaneurysm after the occlusion of the CCF with an incidence of pseudoaneurysm formation of 18.2% (4/22). A total number of 8 patients experienced permanent occlusion of the ICA with a rate of ICA occlusion reaching 36.4% (8/22). Followed up through telephone consultation from 6 months to 5 years, all did well with no recurrence of CCF symptoms and signs. Conclusion Traumatic direct CCFs can be successfully managed with endovascular means. The pseudoaneurysms secondary to the occlusion of the CCFs can be occluded with stent-assisted coiling and implantation of covered stents.  相似文献   

15.
Acute limping may be the result of multiple pathologies in children. The differential diagnosis varies based on the age of the child. Irrespective of age, the initial imaging work-up includes AP and frog leg radiographs of the pelvis and ultrasound; MRI may sometimes be helpful. In children less than 3 years, infections and trauma are most frequent. MRI is the imaging modality of choice when osteomyelitis is clinically suspected. Between the ages of 3 and 10 years, transient synovitis of the hip and Legg-Calvé-Perthes disease are main considerations but infection, inflammation and focal bony lesions are also considered. In children over 10 years, slipped capital femoral epiphysis also is considered.  相似文献   

16.
Introduction Ankle sprains are the most common musculo-skeletal injury that occurs in athletes,particularly in sports that require jumping and landing on one foot such as soccer,and basketball(1-4).These injuries often result in significant time loss from participation,long-term disability,and have a major impact on health care costs and resources(5-8).  相似文献   

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KEY POINTS ·High-intensity interval training(HIT)is characterized by repeated sessions of relatively brief,intermittent exercise.often performed with an“a11 out”effort or at an intensity close to that which elicits peak oxygen uptake(i.e.,≥90%of VO2 peak).  相似文献   

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In response to the ENFSI and EDNAP groups’ call for new STR multiplexes for Europe, Promega® developed a suite of four new DNA profiling kits. This paper describes the developmental validation study performed on the PowerPlex® ESI 16 (European Standard Investigator 16) and the PowerPlex® ESI 17 Systems. The PowerPlex® ESI 16 System combines the 11 loci compatible with the UK National DNA Database®, contained within the AmpFlSTR® SGM Plus® PCR Amplification Kit, with five additional loci: D2S441, D10S1248, D22S1045, D1S1656 and D12S391. The multiplex was designed to reduce the amplicon size of the loci found in the AmpFlSTR® SGM Plus® kit. This design facilitates increased robustness and amplification success for the loci used in the national DNA databases created in many countries, when analyzing degraded DNA samples. The PowerPlex® ESI 17 System amplifies the same loci as the PowerPlex® ESI 16 System, but with the addition of a primer pair for the SE33 locus. Tests were designed to address the developmental validation guidelines issued by the Scientific Working Group on DNA Analysis Methods (SWGDAM), and those of the DNA Advisory Board (DAB). Samples processed include DNA mixtures, PCR reactions spiked with inhibitors, a sensitivity series, and 306 United Kingdom donor samples to determine concordance with data generated with the AmpFlSTR® SGM Plus® kit. Allele frequencies from 242 white Caucasian samples collected in the United Kingdom are also presented. The PowerPlex® ESI 16 and ESI 17 Systems are robust and sensitive tools, suitable for the analysis of forensic DNA samples. Full profiles were routinely observed with 62.5 pg of a fully heterozygous single source DNA template. This high level of sensitivity was found to impact on mixture analyses, where 54–86% of unique minor contributor alleles were routinely observed in a 1:19 mixture ratio. Improved sensitivity combined with the robustness afforded by smaller amplicons has substantially improved the quantity of data obtained from degraded samples, and the improved chemistry confers exceptional tolerance to high levels of laboratory prepared inhibitors.  相似文献   

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