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V. Kyriazis 《Journal of orthopaedics and traumatology》2006,7(1):1-5
Abstract Robotics has been applied to the rehabilitation of patients suffering from upper limb-related diseases such as stroke, upper
spinal cord injuries and neuromuscular diseases (e. g. muscular dystrophy) alone, or combined with appropriate orthotic devices.
In all cases, expensive industrial manipulators, as much as relatively low-cost commercial systems with specific modifications
have been used. However, no reference has been made in the literature on the technology of such devices. This article presents
the development of a joystick-computer system for the control of a step motor. Further research can lead to the development
of an extremely low-cost robotic arm which uses residual finger movement input and can be used by research centers with restricted
funding. Reference is made to the technology on which the circuitry is based, as well as to the design concept of it. 相似文献
54.
T. Hammen F. Kerling M. Schwarz A. Stadlbauer O. Ganslandt B. Keck B. Tomandl A. Dörfler H. Stefan 《European journal of neurology》2006,13(5):482-490
Up to 30% of patients with temporal lobe epilepsy (TLE) remain without remarkable changes in MRI. In this study we investigated the role of (1)H-MR spectroscopy ((1)H-MRS) in lateralizing the affected hemisphere in the mentioned patient group. Twenty-two consecutive patients diagnosed with TLE were investigated by high resolution MRI and (1)H-MRS. We examined the incidence and diagnostic accuracy of temporal metabolite alterations determined by Linear Combination of Model Spectra (L C Model) via water reference. Metabolite values of each hemisphere of TLE patients were compared with healthy controls. Results of metabolite alterations were related to intensive video EEG focus localization. Reduction of N-acetylaspartate + N-acetylaspartyl-glutamate (tNAA) in the affected hemisphere revealed identification in six of nine patients (66%) with unilateral TLE. Group comparison revealed a significant reduction of tNAA (6.1+/-0.8*) in the involved temporal lobe compared with controls (6.67+/-0.4*, P=0.026). Choline levels were significantly increased in the affected hemisphere (1.42+/-0.17*) compared with healthy controls (1.22+/-0.17*, P=0.035). The results of our study show that (1)H-MRS is able to identify the affected hemisphere of MRI negative TLE patients and can be used as an additive tool in multimodal focus localization. 相似文献
55.
本文对19名无喉人食管发音患者,利用X线电影、X线录相及录音技术,对食管发声的机理进行了图、声同步的动态观察与分析。认为食管发声须经过:科学训练;代声门形成;贮气、送气、发音三个时相过程及口腔、鼻腔、舌唇、齿等构字器官的协调配合加工而成。文中还对此项检查设备、方法、检查前准备及步骤进行了详尽论述。 相似文献
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报道30例腕部损伤患者,伤情比较相同。其中12例采用传统外科手术治疗,不作或仅作不正规的理疗;18例采用显微外科技术治疗,仔细修复各种组织结构,术后系统地进行康复治疗。经随访3个月~2年,传统方法治疗组优良率仅为8.3%;采用显微外科技术及康复治疗组优良率达67%。 相似文献
58.
Functional properties of ramified microglia were investigated in primary cultures of rat cerebral cortical cells. These microglia could be readily identified in both fixed and living cultures through previously established features. Based on their destruction by 5 mM L-leucine methyl ester, a high level of intrinsic endocytotic activity was established. When cultures were incubated with fluorescent latex beads to assess phagocytosis, little or no such activity was exhibited by ramified cells. However, when cultures were incubated with dyes or other soluble tracer compounds, these cells always exhibited labeling. This labeling was selective for ramified microglia in the cultures and was demonstrated using a variety of compounds, including trypan blue, lucifer yellow, horseradish peroxidase (HRP), and India ink. Intracellular label could be observed in vesicular structures; this localization corresponded to an active cellular process. Also, cellular labeling was inhibited by the presence of colchicine. These features supported the inference that the labeling was attributable to pinocytosis, and this process appeared to account for the vast majority of endocytotic activity in the ramified microglia. Possible physiological significance of this pinocytotic activity was indicated by the accumulation of various neurotransmitters/modulators: gamma-aminobutyric acid and vasoactive intestinal polypeptide (VIP). Ramified cells in these cultures have been previously noted to exhibit a constant and rapid pattern of motility, which was consistently observed here through time-lapse video recording; pinocytosis and rapid motility were shown to concur in individual cells. Based on their high intrinsic pinocytotic activity and pattern of cellular motility, the ramified microglia specifically are suggested to serve a constitutive function of fluid cleansing within the interstitial spaces of brain tissue. 相似文献
59.
In Vitro Evaluation of Platelet/Biomaterial Interactions in an Epifluorescent Video Microscopy Combined with a Parallel Plate Flow Cell 总被引:1,自引:0,他引:1
Nobuchika Kawagoishi Chisato Nojiri Kazuhisa Senshu Takayuki Kido Hirofumi Nagai Toshiyuki Kanamori Kiyotaka Sakai Hitoshi Koyanagi† Tetsuzo Akutsu 《Artificial organs》1994,18(8):588-595
Abstract: Suitable evaluation systems are critical for ranking various biomaterials in order to develop a method to design and synthesize nonthrombogenic biomaterials. We have recently developed an in vitro test system to evaluate platelet/biomaterial interactions in whole blood. The system consists of a parallel plate flow cell and epifluorescent video microscopy (EVM). A glass coverslip coated with a polymer was incorporated into the flow cell, and blood was perfused using a syringe pump via a polymer–coated PVC tubing connected to the flow cell. Whole human blood was anticoagulated with heparin (2 U/ml), and the platelets were labeled with the fluorescent dye mepacrine (5 μM). This system permitted real–time and dynamic observations of platelet/biomaterial interactions in whole blood under a defined flow condition. In order to evaluate the feasibility of this system, two different segmented polyether–polyurethanes (SPEUs), PU–PTMG(650) and PU–PTMG(2000), were chosen as test polymers. Surface characteristics verified with electron spectroscopy for chemical analysis (ESCA) and contact angle measurements showed similar results in both SPEUs. Blood was perfused at a wall shear rate of 200 s–1 for 20 min. Excitation light was applied for 2 s at 1 min intervals. The real–time image was then analyzed at each time point for the percentage of surface area of platelet coverage. Plasma β–thromboglobulin (β–TG) levels were also measured before and after each run. PU–PTMG(650) showed a significantly higher number of adhered platelets than PU–PTMG(2000) at each time point. β–TG levels of PU–PTMG(650) were also higher than those of PU–PTMG(2000), which is comparable to the results of EVM. Thus, this EVM system has been proven to be an excellent and highly sensitive in vitro analytical method for evaluating platelet/biomaterial interactions. 相似文献
60.
Video feedback has been shown to increase performance estimates on the part of speech anxious individuals (R. M. Rapee & K. Hayman, 1996). The present experiment tested a video feedback condition against 2 control conditions. A possible moderator of video feedback effects, the degree to which participants underrated their initial speech, was also tested, as was the possibility of mediation of video feedback's effects by increases in self-efficacy. Participants were 90 speech anxious undergraduate students. Although video feedback showed transitory effects across the sample as a whole, the effect was consistently positive for participants who highly underrated their first speech. Self-efficacy was an important predictor of change in self-perception of performance, but was not a mediator of video feedback's effects. 相似文献