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71.
Rupp A  Gutschalk A  Hack S  Scherg M 《Neuroreport》2002,13(17):2203-2207
The temporal resolution of the primary auditory cortex was studied by recording the magnetic middle latency fields (MAEF) evoked by gaps of 3, 6 and 9 ms inserted in the middle of 600 ms broadband noise bursts. Spatio-temporal source modelling showed that a significant neural representation as reflected by MAEF responses is present at gap durations as low as 3 sms. The comparison of the MAEF waveforms elicited by the onset, gap and offset of the noise bursts indicates that the gap related response near threshold is largely determined by the onset to the burst following the gap. The electro-physiologically derived minimum detectable gap closely resembled the psychoacoustic threshold of 2.0 ms obtained in the same subjects.  相似文献   
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目的:优选伤湿止痛流浸膏的提取工艺。方法:采用正交试验法考察药材浸泡时间、煎煮时间、溶媒pH值、药液处理方法对提取工艺的影响。结果:确定最佳提取工艺为溶媒pH3~4的酸水,药材浸泡12h,煎煮6h,药液75%醇沉处理。结论:按优选的最佳提取工艺条件,以指标性成分士的宁的得率为指标,预测并验证试验结果满意。  相似文献   
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The aim of this study was to evaluate the effect of extracorporal shock wave therapy (ESWT) in tennis elbow and painful heel. Nineteen patients with tennis elbow and 44 patients with painful heel in which conservative treatment had failed underwent ESWT. Both groups received 3000 shock waves of 0.12 mJ/mm2 three times at weekly intervals. After a follow-up of 5 and 6 months respectively, pain measured on a visual analogue scale (VAS) decreased significantly in both groups. The success rate (excellent and good results) was 63% in tennis elbows and 70% in painful heels. ESWT seems to be a useful conservative alternative in the treatment of both conditions.  相似文献   
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The objective was to verify different reports in the literature which show an increase of stability using vacuum-mixing of bone cement, by testing the fatigue properties of bone-cement specimens (Palacos R). Evacuation of the poly(methyl-methacrylate) (PMMA) and evacuation with additional pressurization (Draenert system) were used to manufacture the specimens. Although we found improvement in the ultimate bending strength for evacuated Palacos R, an increase of fatigue stability could not be found either for vaccum-mixed cement or for vacuum-mixed and compressed cement. As fatigue failure is one of the most important factors leading to aseptic loosening of cemented alloarthroplasties, we conclude that the long-term results cannot be improved by vaccum-mixing this cement.  相似文献   
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To compare the effect of halothane and enflurane on an atracurium-induced neuromuscular blockade, the authors studied 40 patients during elective surgery. During 1.25 MAC enflurane-nitrous oxide (n = 20) or halothane-nitrous oxide (n = 20) (MAC value includes contribution from 60% nitrous oxide), the doses depressing twitch tension 50% (ED50S) for atracurium were 70 and 77 micrograms/kg, respectively. The difference was not significant. Time from injection to peak effect did not differ between groups. However, the duration of action of atracurium (expressed as duration 50 or the duration of a 50% blockade) was longer during enflurane-nitrous oxide anesthesia (34.2 min) than during halothane-nitrous oxide anesthesia (25.5 min) (P less than 0.05). The authors conclude that the potency of atracurium does not differ during halothane-nitrous oxide and enflurane-nitrous oxide anesthesia. Combining the results of this study with a previous study (atracurium ED50 = 68 micrograms/kg and 83 micrograms/kg during isoflurane-nitrous oxide and fentanyl-nitrous oxide anesthesia respectively), the potency of atracurium does not differ by more than 20% among the four anesthetic techniques studied. The background anesthetic appears to have less effect on an atracurium-induced neuromuscular blockade than on one produced by other longer-acting nondepolarizing muscle relaxants (e.g., pancuronium and d-tubocurarine).  相似文献   
77.
New compounds of the nitroimidazole series have been synthesized as radiosensitizers which selectively sensitize hypoxic cells to the lethal effect of radiation. The reaction of 2,4(5)-dinitroimidazole (2) with chloroethanol or hydrochloric acid yielded 4(5)-nitro-5(4)-chloroimidazole (3), which upon reaction with ethylene oxide yielded the 4-nitro-5-chloroimidazole-1-ethanol (6). Reaction of 2 with ethylene oxide resulted in a mixture of two compounds, the 2,4-dinitroimidazole-1-ethanol (4) and 2,3-dihydro-5-nitroimidazo[2,1-b]oxazole (5). The structure of the new heterocyclic compound 5 was confirmed by 1H NMR, mass spectrum, and X-ray crystallography. These agents were tested for their ability to sensitize hypoxic Escherichia coli cells to killing by ionizing radiation. Compound 4 was found to be the most active agent of this series of compounds.  相似文献   
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Introduction The aim of this study was to investigate the effect of extracorporeal shock wave therapy (ESWT) on the ultrasonographic appearance of chronically painful, proximal plantar fasciitis.Materials and methods Twenty-two patients with a unilateral proximal plantar fasciitis were prospectively enrolled after unsuccessful conservative treatment lasting 6 months. The contralateral plantar fascia was used as the control. ESWT (3×3000 shock waves/session of 0.2 mJ/mm2) was performed at weekly intervals. The thickness of the plantar fascia was measured ultrasonographically about 2 cm distal of the medial calcaneal tuberosity. Pain estimation on a visual analogue scale (VAS) and the comfortable walking time were recorded. No local anaesthesia was applied. Follow-up was done at 6, 12 and 24 weeks.Results Before ESWT, the plantar fasciitis side was ultrasonographically significantly thicker than the control side (p<0.05), whereas 6 months after ESWT, the thickness of the fascia was no longer significantly different. The decrease in thickness of the plantar fasciitis side was significant (p<0.05). Pain during activities of daily living decreased by 79% according to the VAS, and the comfortable walking time increased, both significantly (p<0.01). In patients with little pain (VAS<30), the thickness of the plantar fasciitis side was significantly less (p<0.01) compared with patients who still suffered more pain (VAS>30).Conclusion After ESWT, the thickness of the plantar fascia in patients with plantar fasciitis decreased, pain and walking time improved (all significantly).  相似文献   
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