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B. Blad   《ITBM》2006,27(5-6):238-242
Deep brain stimulation, DBS, is an accepted technique for the treatment of Parkinson's disease. DBS affects the electrical functions of neurons, but exactly how it alters those functions is not clearly explained. An electrical model is determined to simulate treatment with DBS of the sub thalamic nucleus. This model shows the difference in electrical fields between the inside and the outside the neurons. The generated electrical field near the electrodes is high enough to perform an electropermeabilization of the cell membranes, which most likely blockade normal nerve pulses or reduce the nerve impulse speed. Further away from the electrodes activation of large axons is performed.  相似文献   
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Zusammenfassung Adh?sionsmoleküle sind Zell-Oberfl?chen-Proteine, welche verantwortlich sind für die Zell-Zell- und Zell-Matrix-Interaktionen. Sie sind in der Lage eine gro?e Zahl von Stimuli zu erkennen und darauf entsprechend zu reagieren. Sie bilden somit eine Basis für manchen physiologischen und pathologischen Prozess insbesonders des „Homing“-Verhaltens, der Homeostase der Immunantwort, der Wundheilung, der Entzündungen und der Tumormetastasierung. In der Dermatologie wurde das Interesse vor allem durch die Entdeckung des CLA (cutaneous lymphocyte antigen) geweckt, welches der spezifische „Homing“-Rezeptor für Memory-T-Zellen darstellt. So konnte gezeigt werden, da? die Zellen in kutanen Lymphomen CLA-positive T-Zellen sind, im Gegensatz zu prim?r nodalen Non-Hodgkin Lymphomen, wo die T-Zellen CLA negativ sind. Neuere Arbeiten haben gezeigt, da? die Adh?sionsmoleküle wie CD44v6 bei kutanen Lymphomen, welche eine systemische Ausbreitung zeigen, auf den Tumorzellen exprimiert werden und somit eine entscheidende Rolle in der Metastasierung dieser Tumoren darstellen. Eingegangen am 27. November 1995 Angenommen am 22. Dezember 1995  相似文献   
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Refractoriness to Gal N toxicity occurs especially in fetal rats, newborn rats, and in rats after partial hepatectomy. An injury however (laparotomy, incision on the back or ip BaSO4 suspension), prior to Gal N administration, also inhibits Gal N toxicity. In all these circumstances high levels of rat α2-macrofetoprotein (αMFP) occur. This protein is an acute phase reactant and is identical to rat α2-macroglobulin. αMFP isolated from the serum of injured rats and then administered to normal rats strongly inhibits Gal N toxicity. When time interval between the preceding injury, provoking αMFP production and Gal N administration shortens, the inhibiting effects are less and αMFP production remains low.During resistance to Gal N, the primary and secondary biochemical lesions of Gal N persist and the protecting effect of αMFP must be due to another mechanism, operating in later phases of cell injury. Very probably this is attributable to the stabilizing effect on membranes of hepatocytic organelles and the plasma membranes. As αMFP is an acute phase reactant the importance of these proteins to the course of hepatitis must be considered.  相似文献   
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GAP-43 is normally produced by neurons during developmental growth and axonal regeneration, but it is also expressed in specific regions of the normal adult nervous system. We studied the protein expression of GAP-43 within the conus medullaris portion of the spinal cord in adult male rats. Immunohistochemistry for choline acetyltransferase (ChAT) was first performed to identify specific efferent autonomic and motor nuclei in lumbosacral segments of the spinal cord. Adjacent sections were then processed for GAP-43 immunoreactivity (IR). We show GAP-43 IR in the superficial portion of the dorsal horn, the intermediolateral nucleus, and the dorsal commissural tract. We also demonstrate a differential distribution of GAP-43 IR between different motor nuclei of the conus medullaris. Using densitometry, the most prominent GAP-43 IR was detected in the dorsolateral and dorsomedial motor nuclei, which represent the human Onufs nucleus homologue. Confocal microscopy of double immunofluorescent labeling for ChAT and GAP-43 demonstrate GAP-43 IR in the neuropil of the autonomic and motor nuclei, and many of the GAP-43 IR arbors are in close apposition with the efferent cholinergic neurons. We note that the efferent neurons of both the autonomic and somatic nuclei, which are ultimately responsible for the integrated normal control of the lower urinary tract, bowel and sexual functions, are heavily innervated by GAP-43 enriched projections. We speculate that these functionally related neurons retain a physiological GAP-43-associated synaptic plasticity throughout adult life.  相似文献   
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D. Istrate  M. Vacher  L. Besacier 《ITBM》2006,27(2):35-45
The telemedicine and medical remote monitoring in particular, today represents an effective solution to the health professional shortcomings facing to the increasing older population. In addition to the comfort of being at home, this system decreases the cost of long hospitalization. The proposed system achieves the home medical telesurveillance by means of microphones and medical sensors to detect a distress situation. This system is designed for elderly people at home or for the patient with chronic illness. The experimental apartment is equipped with medical sensors (tensiometer, oxymeter, balance, etc.), infrared position sensors, and acoustic sensors (1 microphone/room). The originality of the system comes from the replacement of the video surveillance with a sound surveillance. The sound analysis system is divided in two stages: firstly, the detection/extraction of the sounds is operated and secondly, a classification of these sounds in known classes takes place. A wavelet-based algorithm with good performance when applied in noisy environments is proposed. The acoustical classification step uses a Gaussian Mixture Models to classify the sounds according to the 7 predefined classes. The detection algorithm allows an equal error rate of 0% for the signal to noise ratio superior or equal to 10 dB and 4% for the 0 dB. The proposed system coupled with a classical medical telesurveillance system will bring extra information needed for the reliability of the global system.  相似文献   
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BackgroundHepatitis C virus (HCV) infected patients have been found to be more susceptible to metabolic syndrome (MetS), but the results remain unclear and lack of a meta-analysis.MethodsDatabases including PubMed, Web of Science, EMBASE and the Cochrane Library were searched to identify all studies concerning HCV and MetS. Funnel plots combined with Begg's tests and Egger's tests were used to analysis the possible publication bias. The odds ratios (ORs) with 95% confidence intervals (CIs) were used to access the effect of HCV infection on the risk of MetS.ResultsEight articles, involving a total of 57387 HCV patients were included. HCV infection was significantly associated with an increased incidence of MetS (OR = 1.73; 95% CI, 1.19–2.52). After adjustment according to the sensitivity analysis, one included article was removed to decrease the publication bias and high heterogeneity, of which the results showed that HCV infection was still associated with an increased incidence of MetS (OR = 1.93; 95% CI, 1.39–2.68).ConclusionsHCV patients tend to have a significant increased risk for MetS, but more large-scale studies are needed to confirm this and explore the exact mechanism.  相似文献   
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丹参酮胶囊治疗结节囊肿性痤疮的临床疗效评价   总被引:1,自引:1,他引:1  
目的 :观察丹参酮治疗结节囊肿性痤疮的临床疗效。方法 :选择符合标准的一组患者 (共 3 5例 ,3 1例完成观察 ) ,口服丹参酮胶囊 (0 .2 5g 粒 ) ,每次4粒 ,每日 3次 ,连服 8wk后 ,改为每次 3粒 ,每日 3次 ,总疗程共 1 2wk。结果 :治疗的总有效率为83 .9% ,治疗 2、4、8、1 2wk后结节囊肿性皮损平均数目分别是 1 9± 9、1 5±6、1 0±6和 7± 7(P <0 .0 1 ) ,与治疗前 (2 3±1 1 )比较 ,P <0 .0 1。结论 :丹参酮对结节囊肿性痤疮有较好的临床疗效 ,随疗程的延长有效率逐渐增加  相似文献   
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