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1.
A novel cardiokymograph system is introduced. The new system features a capacitance transducer with increased sensitivity and can be used in multichannel measurements. The novelty of this technique is the injection of a current into the patient coupled with the use of a capacitive displacement transducer and the possibility of multichannel monitoring. It provides for the possibility of removing breath noise when some signal processing technique, such as adaptive filtering, is used. Further investigation is needed to demonstrate clinical significance and pathologies.  相似文献   
2.
An acceleration transducer elicits an output voltage proportional to the deformation of the piezo crystal, in accordance with the twitch responses of the applied fingers. The reliability of such a transducer was evaluated by comparing induced twitch responses with those from a force transducer applied on the contralateral arm of an individual during neuromuscular block with vecuronium. The results obtained from twitch responses with the acceleration transducer during neuromuscular block were almost identical to those obtained with the force transducer. Also, the twitch heights due to acceleration of the examined thumb correlated extremely well with the twitch height due to twitch tension with the force transducer. It is concluded that the acceleration transducer may be a useful and reliable device for monitoring neuromuscular block, although responses during tetanic stimulation such as tetanic fade cannot be determined by the transducer.  相似文献   
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A new and simple acceleration transducer (ACT)–based system of neuromuscular monitoring has recently been introduced. The precision of this transducer has been evaluated as compared to a conventional force displacement transducer (FDT) in the present study. Ten progressions of spontaneous recovery from atracurium–induced block with simultaneous measurements using the ACT on one hand and the FDT on the other were studied. Five individuals undergoing elective surgery in modified neurolept anaesthesia and one ICU–patient requiring prolonged neuromuscular blockade, sedated with pentobarbital, were included. Measurements were carried out on the latter patient on 5 consecutive days. Train–of–four (TOF) stimulation was used, readings were given in twitch heights (TH) (Tl/control value), and when four responses were obtained in TOF–ratios (T4/T1). Linearity was achieved after logit–transformation and the values regressed on time for each progression of recovery. Analysis of variance was applied to the regressions for the TH and TOF–ratio readings of each transducer. No significant differences were found, either between variation due to differences between slopes or variation due to technical error between the two transducers. The study indicates that the ACT is equal to the FDT with regard to precision in clinical recordings on atracuriumrelaxed individuals.  相似文献   
4.
目的研究人脑不同级别胶质瘤中白细胞介素(IL)-6,信号传导和转录活化因子3(STAT3)和血管内皮生长因子(VEGF)的表达,探讨IL-6、STAT3和VEGF与肿瘤病理级别和侵袭性的关系。方法采用免疫组织化学法,检测70例人脑胶质瘤,10例脑膜瘤和5例正常脑组织中IL-6、STAT3和VEGF的表达。结果胶质瘤中IL-6、STAT3和VEGF的表达水平在高级别组(Ⅲ、Ⅳ级)明显高于低级别组(Ⅰ、Ⅱ级),两组间差异有统计学意义(P〈0.01),STAT3的表达与IL-6和VEGF的表达均呈正相关(P〈0.01)。结论IL-6、STAT3和VEGF的表达与胶质瘤的恶性程度有密切关系;且三者协同在胶质瘤发生、发展过程中起重要作用。三者的相关性证实VEGF基因由STAT3蛋白调节,而STAT3又由IL-6刺激活化。  相似文献   
5.
A new method for monitoring neuromuscular function based on measurement of acceleration is presented. The rationale behind the method is Newton's second law, stating that the acceleration is directly proportional to the force. For measurement of acceleration, a piezo-electric ceramic wafer was used. When this piezo electrode was fixed to the thumb, an electrical signal proportional to the acceleration was produced whenever the thumb moved in response to nerve stimulation. The electrical signal was registered and analysed in a Myograph 2000 neuromuscular transmission monitor. In 35 patients anaesthetized with halothane, train-of-four ratios measured with the accelerometer (ACT-TOF) were compared with simultaneous mechanical train-of-four ratios (FDT-TOF). Control ACT-TOF ratios were significantly higher than control FDT-TOF ratios: 116 +/- 12 and 98 +/- 4 (mean +/- s.d.), respectively. In five patients not given any relaxant during the anaesthetic procedure (20-60 min), both responses were remarkably constant. In 30 patients given vecuronium, a close linear relationship was found during recovery between ACT-TOF and FDT-TOF ratios. It is concluded that the method fulfils the basic requirements for a simple and reliable clinical monitoring tool.  相似文献   
6.
A prototype electronic radial scan ultrasound endoscope has been developed by Olympus (Tokyo, Japan) for endoscopic ultrasound (EUS) study. The ultrasound view‐angle of this model is 360° vertical to the scope. Though the diameter of the scanner and the shaft of the scope is bigger than those of the present mechanical radial scan model, clinical manipulation of the new scope is the same as that of the present model. Image quality of the ultrasound picture demonstrated by the electronic radial model was as clear as those provided by the mechanical radial scan model. Ultrasound penetration was better and satisfactory because of less echoic reduction compared to the mechanical radial model. The newly developed electronic radial model can be evaluated as an ultrasound endoscope for the next generation. The advantage of this system is to facilitate the clinical use of color Doppler function and tissue harmonic imaging, and this system can be operated by the same monitor unit as a convex model of ultrasound endoscope.  相似文献   
7.
本文报道由我们研制的氢离子半导体传感器的性能特点,并与普通离子选择电极(玻璃电极)比较。H^+-ISFET具有体积小、取样少、快速、稳定、全固体化、不用预先活化等优点,对氢离子的敏感性也优于普通玻璃电极。本文还成功地将H^+-ISFET应用于有复杂成分并存的尿、血及其他生物材料的pH值测试,并改进胆碱酯酶活力测定方法,将H^+-ISFET应用于有机磷中毒后胆碱酯酶活力的快速定量测定。  相似文献   
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