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31.
Summary The relationship between the concentrations of 5-hydroxyindoleacetic acid (5-HIAA) in the CSF and in the striatum has been evaluated in the rat by measuring the levels of this metabolite in ventricular CSF (by liquid chromatography coupled with electrochemical detection) and in the striatal extracellular fluid (byin vivo voltammetry) after administration of inhibitors of serotonin synthesis or degradation. Pargyline, NSD 1015 and-propyldopacetamide all caused an exponential decline of 5-HIAA in both CSF and striatum. For a given drug, the rate constants for 5-HIAA disappearance were identical in the CSF and in the striatal extracellular fluid. These results confirm the view that CSF 5-HIAA may serve as a good index of brain serotonin turnover.  相似文献   
32.
IntroductionThe repair of a deltoid ligament injury, following an ankle fracture with involvement of the syndesmosis, has no univocal consensus. Also the surgical strategies in case of a subsequent chronic instability are still under debate. In this work the result of a double bundle anatomic reconstruction of deltoid ligament with ipsilateral autologous gracilis muscle tendon is presented.Case reportA 50 year old active male patient came to our attention with a catastrophic medial ankle instability, a severe pronation of the hindfoot and disabling ankle pain. He reported a Weber type B fracture of the left ankle with a lesion of the syndesmosis treated with anatomic plate and screws and a transyndesmotic screw 8 months before. The imaging showed a complete deltoid ligament lesion. Due to the impossibility of a direct repair of the ligament, we performed the reconstruction of the medial ligamentous complex with an autologous gracilis tendon graft. 10 months after the medial ligamentous complex reconstruction, the patient showed an excellent recovery of walking ability, disappearance of pain under load and resumed an active lifestyle.DiscussionThe deltoid ligament has a key role in ankle joint stability and its integrity promotes the recovery after ankle fractures. However, its lesion is often left untreated in the acute setting. The result of a chronic untreated deltoid ligament injury could be extremely disabling and the ligament reconstruction, when an optimal native deltoid ligament repair is not achievable, is the choice to restore ankle function and stability.ConclusionIn the delayed treatment of a deltoid ligament rupture the described double bundle anatomic reconstruction with autologous tendon graft can be an effective and suitable option.  相似文献   
33.
BackgroundIn severe cases of ankle and subtalar arthritis, arthrodesis of the subtalar joint is performed in combination with ankle arthroplasty. In these special cases gait analysis reveals real motion at the replaced tibiotalar joint.MethodsTwenty-three patients affected by ankle and subtalar arthritis, treated either with a 3-component or a 2-component prosthesis in combination with subtalar arthrodesis, were clinically evaluated preoperatively and at a minimum of 1-year follow-up. Gait analysis was performed postoperatively using a multi-segment foot protocol. Foot kinematics were compared to corresponding data from a healthy control group.ResultsClinical scores significantly improved from preoperative to follow-up. The clinically measured passive ankle dorsiflexion/plantarflexion significantly improved at the follow-up. Patients’ normalized walking speed and stride length were significantly lower than those in control. With exception of the ankle frontal-plane motion, sagittal-plane mobility of foot joints was about 50% than that in healthy joints.ConclusionsImprovement in clinical scores was found for both prostheses. Normal spatio-temporal parameters were not restored. In these patients, fusion of the subtalar joint appeared to be compensated by larger frontal-plane motion at the tibiotalar joint.Level of evidenceLevel III- retrospective comparative study.The study was approved by the local Ethics Committee as protocol MAT (protocol registration at clinicaltrials.gov NCT03356951).  相似文献   
34.
BackgroundOur aim in this study was to identify the fibular footprint of the Anterior Inferior Tibiofibular Ligament (AITFL) and its relation to Wagstaffe fracture fragment size.MethodsWe examined 25 cadaveric lower limbs which were carefully dissected to identify the lateral ankle ligaments. The AITFL anatomy was compared to 40 Wagstaffe fractures identified from our ankle fracture database.ResultsThe AITFL origin was from the anterior fibular tubercle with an average length of 21.61 mm (95% CI 20.22, 22.99). The average distance of the distal aspect of the AITFL footprint to the distal fibula margin was 11.60 mm (95% CI 10.49, 12.71). In the ankle fractures analyzed, the average length of the Wagstaffe fragment was 17.88 mm (95% CI 16.21, 19.54). The average distance from the distal tip of the fibula to the Wagstaffe fracture fragment was 21.40 mm (95% CI 19.78, 23.01).In total there were 22 syndesmosis injuries. There was no statistical difference in Wagstaffe fragment size between stable and unstable groups.ConclusionThe AITFL fibular origin was both larger and more distal than the Wagstaffe fracture fragments seen in our institution. Therefore, this suggests that a ligamentous failure will also have to occur to result in syndesmotic instability. The size of fracture fragment also did not confer to syndesmotic instability on testing.Level of Evidence - 3  相似文献   
35.
Summary The contours of pressure and flow of a pulse wave arriving at the entrance of a collapsed segment of an elastic tube can be described by application of the basic laws of reflection. The collapsed segment acts like a valve. It is opened by the pressure of the pulse wave when the pressure within the tube becomes higher than the collapse pressure, i.e. the pressure exerted on the segment from outside. This opening of the collapsed segment suddenly changes the sign of the pulse wave reflection from positive to negative; thus a typical contour change of the pulse proximal to the segment is observed. The most obvious effect is a reduction of the pulse pressure. The extent of this reduction is a function of the collapse pressure.A typical example of this phenomenon can be observed in an artery proximal to the segment which is collapsed due to the pressure exerted by an inflated Riva-Rocci cuff. The effect is explained by the assumption that the sign of reflection changes when the pressure of the pulse wave crosses the level of the cuff pressure. This explanation is supported by the results of model experiments.  相似文献   
36.
Summary For determination of trace Se we used high-pressure wet digester to pretreat the specimens obtained from the human body. This method is very effective in preventing loss of Se by volatilization which often occurs in the sample pretreatment. We studied the method of using anodic stripping voltammetry at gold-disc electrode to measure the trace Se present in the human body and found it to be the optimal procedure. The detection limitation was about 2x10−8 g/L, the recovery rate of Se about 96.6±6,7 % , and the coefficient of variation CV = 7.0%.  相似文献   
37.
人体胆结石高能震波碎石的动物实验   总被引:2,自引:2,他引:0  
目的 研究人体 3种胆结石在一定能量下 ,冲击次数和能量的关系 ,确定不损伤胆囊和小肠内膜的能量安全阈值 .方法 犬胆囊和小肠内放入固醇石、混合石和色素石 ,在不同的输出电压下 ,放电碎石 .结果 固醇石、混合石和色素石破碎所需的能量不同 ,在同样电压下 ,固醇石所需的次数最少 ,混合石次之 ,色素石最多 ;病理检查表明 ,在电压 <15 k V时 ,胆囊和小肠粘膜处 ,细胞膜轻度充血 ,出现小出血点 .当电压 >15 k V后 ,粘膜有脱落 ,膜下组织水肿 .结论 电压具有依赖性 ;该仪器临床应用的冲击电压应小于 15 k V  相似文献   
38.
【目的】研制一个计算机辅助的心血管信号检测和处理系统。【方法】本系统的硬件设计采用奔腾 Ⅱ / 2 33多媒体微机系统 ,多路模 /数转换器和心电电极、心音传感器、脉搏波传感器及由运算放大器等构成相关的放大器及滤波器。本系统采用可视化编程环境构建系统结构和功能模块设计的方法 ,基于多媒体技术和小波变换原理 ,在 32位Windows平台下 ,利用可视化编程语言VisualC 6 0和多媒体著作工具Authorware等进行系统的软件设计。【结果】本系统能完成心电、心音、脉搏波信号检测和处理 ,并将结果以图、文、声并茂的形式显示、打印或播放 ,还具有病案管理和心音听诊多媒体计算机辅助教学功能。【结论】它是一个新型的多功能心血管信号检测和处理系统。  相似文献   
39.
目的为探讨压力波的致聋机理,对豚鼠耳蜗血管纹(SV)、毛细胞(HC)中心钠素免疫活性(ANP-IR)的改变及与听阈阈移的相关性进行研究。方法采用免疫细胞化学(ABC法)法、图像分析听性脑干反应测听技术(ABR)对压力波暴露后不同时间分组的豚鼠耳蜗SV、HC中ANP-IR产物进行检测。结果压力波暴露后6、12、24h和48h组SV组织中ANP-IR光密度值较对照组均有明显的差异(P<0.05),其中24h组最高;冲击波暴露后6、12、24h组内毛细胞(IHC)中ANP-IR阳性产物的光密度值较对照组明显增高(P<0.05),其中以12h组最高。二者的变化均与听阈阈移有明显的正相关性(r1=0.8175,P>0.05;r2=0.9185,P>0.05)。而外毛细胞(OHC)中ANP-IR阳性产物变化不明显。结论压力波暴露后,SV组织中ANP的增高可能是内耳的一种代偿机制;IHC和OHC中ANP-IR的变化可能是冲击波对其损伤机制的不同表现。  相似文献   
40.
Mohler J  Hart SC 《Air medical journal》1994,13(11-12):479-482
INTRODUCTION: Traditional methods of determining blood pressure may be unreliable (auscultation or palpation) or unavailable (direct arterial cannulation) in the air medical environment. The authors investigated the combination of a pulse oximeter with a standard sphygmomanometer (blood pressure) cuff as an alternative method. METHOD: The pulse oximeter is applied to a finger on the same upper extremity on which a standard blood pressure cuff had been applied. A baseline blood pressure was obtained by palpation or an automated blood pressure device. One minute later, the systolic blood pressure (SBP) was determined by inflating the blood pressure cuff until the pulsatile display on the pulse oximeter was obliterated. This was taken as the systolic blood pressure. RESULTS: Complete data were obtained on 116 patients, with 223 data pairs. The SBP as obtained by the baseline method was strongly correlated with the SBP obtained by the pulse oximeter display obliteration method (r = 0.90, p < 0.001). CONCLUSION: The obliteration of the wave form display on a pulse oximeter is an accurate, convenient, inexpensive and readily available alternative method of determining SBP.  相似文献   
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