非水介质中明胶水凝胶电场驱动行为的研究

研究了明胶水凝胶在绝缘硅油中的电场响应行为。结果表明,在硅油中,明胶水凝胶在外加高压直流电场作用下可发生运动,其运动由转动和平动两部分组成。存在一个运动所需的最小阈值电场,只有外加电场在此阈值以上时,才可观察到水凝胶明显的运动。水凝胶的运动速度随外加电场的增大而增大,其运动可通过外加电场的大小来调控。由硅油很稳定且在电场中会电解,因此避免了传统电场驱动水凝胶在水介质中响应时不可避免的电解缺点,为建立一种新的电响应凝毅然驱动方式提供了可能。     

PVA／PAA水凝胶纤维的电刺激响应性能

以过硫酸胺为引发剂,在PVA水溶液中原位聚合丙烯酸单体,得到的PVA／PAA混合水溶液在凝固浴硫酸胺饱和水溶液中纺丝制备了物理缠结和氢固定网络形式的PVA／PAA水凝胶纤维。该纤维于NaCl溶液中在直流电场作用下具有电流－刺激敏感性,表现为溶胀、收缩、弯曲行为。纤维的弯曲速度和最大弯曲度随电场强度和凝胶网络中PAA含量的增加而增大,随电解质溶液离子强度的变化出现临界最大值。纤维向负极弯曲的过程中,在电场下自由离子和反庆子迁移引起的渗透压主导作用,弯曲过程主要是溶胀弯曲;向正极弯曲过程中,由于电化学反应和电场作用下产生的PH梯度导致凝胶网络构像变化主导作用,弯曲主要是收缩弯曲;弯曲由负极向正极转化过程中,两种机理对弯曲的影响相对平衡。     

直流电场对鸡胚绒毛尿囊膜血管生成作用的研究

目的：探讨直流电场（electric fields．EF）对血管生成的影响及作用机制。方法：于发育第8天的鸡胚绒毛尿囊膜（chick embryo chorioallantoic membrane，CAM）上植入明胶海绵载体，其中加载不同强度EF，计数长入载体的血管和载体内的微血管密度（microvascular densily．MVD）。结果：150mV／mm、200mV／mm组在CAM上长入载体边缘的血管数和MVD与对照组间的有显著差别（p〈0．01）。结论：强度为150mV／mm、200mV／mm的直流电场能促进CAM的血管生成。     

Magnetic and electrical stimulation of undulating nerve fibres: a simulation study

Mathematical models of myelinated nerve fibres are highly stylized abstractions of real nerve fibres. For example, nerve fibres are usually assumed to be perfectly straight. Such idealizations can cause discrepancies between theoretical predictions and experimental results. One well-known discrepancy is that the currently used models predict (contradictory to experimental findings) that an activation of nerve fibres is not possible with a pure transverse electric field. This situation occurs when a magnetic coil is placed symmetrically above a straight nerve fibre for magnetic nerve stimulation, or when an anode and a cathode are placed equidistantly on a line perpendicular to the fibre in the case of electrical stimulation. It is shown that this discrepancy does not occur if the physiological undulation of peripheral nerve fibres is included in the models. Even for small undulation amplitudes (e.g. 0.02 mm), it is possible to activate the fibre in these positions. For physiological undulations, as found in the literature, and favourable (off-centre) positions, the typical reduction of the thresholds is in a range between one and five, compared with perfectly straight fibres.     

穴位体表电刺激对术后PCEA的强化效应

目的　观察穴位体表电刺激对术后患者硬膜外自控镇痛（PCEA）效果、镇痛药用量、血清皮质醇浓度和不良反应的影响。方法　 选择经腹全宫切除术患者40例（ASAⅠ～Ⅱ级）,随机分成二组,每组20例。A组：于术后第4,8小时 Han's各刺激30 min,术后行PCEA。B组：单纯行术后PCEA（对照组）。术后随访镇痛效果、镇静评分、布氏舒适评分（BCS）,分段记录24 h镇痛药用量及总按压次数/实进次数（D1/D2）比值,血清皮质醇含量,肛门恢复排气时间和不良反应情况。结果　两组镇痛效果满意,A组BCS评分高于B组（P＜0.05）。A组镇痛药用量为（31.7±1.9）ml,与对照组（34.2±2.1）ml相比差异有显著性（P＜0.01）。血清皮质醇浓度两组均较术前下降,但A组术后8 h的下降幅度大于对照组。A组恢复肛门排气时间快于B组,而且恶心、呕吐与对照组相比有所减少。结论　术后患者硬膜外腔自控镇痛（PCEA）复合应用穴位体表电刺激,可增强镇痛效果,减少用药量,降低不良反应,是安全有效的复合镇痛方法。     

Experimental analysis of the human perception threshold of a DC electric field

To study the biological effects of extremely low frequency (ELF) electric fields, a fundamental study is conducted of the human perception threshold of an electric field. The perception threshold is measured with human subjects, and the results are analysed. It is clear that field perception is based on the movement of hair and not on other sensations. Variance in the perception threshold and its causes are investigated. The perception threshold decreases by almost 30% as the relative humidity increases from 50 to 90%. The perception threshold is also dependent on the physical condition (length and density) of the hair and the psychological condition (degree of awareness) of the subject. The dependence on these is much smaller than that on relative humidity. The cause of the gender difference in the threshold is ascribed to the difference in the physical condition of the hair. Through this study, some factors to be taken into account for the safety standard are made clear.     

重症肌无力重复神经电刺激检测的比较研究

目的比较肘肌、三角肌、小指展肌重复神经电刺激（RNS）对重症肌无力（MG）的诊断价值。方法应用低频RNS技术对18例MG患者的肘肌、三角肌、小指展肌进行疲劳前后的检测,用DANTECounterpoint肌电图仪记录。结果对照组肘肌、三角肌、小指展肌疲劳前RNS电压分别降低了1．54％±1．32％、1．64％±1．43％、0．62％±0．38％;疲劳后RNS电压分别降低了2．01％±1．75％、2．05％±1．98％、1．02％±0．75％。MG组肘肌、三角肌、小指展肌疲劳前测试阳性分别为9／18（50％）、10／18（55．6％）、3／18（16．7％）（P均＜0．05）;疲劳后RNS测试阳性分别为15／18（83．3％）、14／18（77．8％）、6／18（33．3％）（P均＜0．05）。经卡方检验,肘肌疲劳前后RNS测试阳性率有显著性差异（P＜0．05）。小指展肌、三角肌疲劳前后RNS测试阳性率对比无显著性差异。结论MG患者肘肌疲劳后RNS阳性率较疲劳前明显增高,而三角肌、小指展肌疲劳前后RNS阳性率无显著性差异;肘肌、三角肌RNS测试较小指展肌更敏感,但肘肌RNS方法简便,病人不适程度轻,有较大的临床实用价值。     

良导络测量系统的理论应用与远景分析

本文通过目前有关良导络测量系统的理论与研究近况,分析其应用于传统医学研究的价值,指出其用于经络腧穴电性研究相关理论的可行性及其意义.