On the electrical capacitance of interfaces exhibiting constant phase element behaviour

It is stressed that any attempt to characterise the interfacial double layer exhibiting a constant phase element (CPE) behaviour by electrical capacitance is misleading. The only possibility to obtain the value of the interfacial double layer capacitance is to ascribe to the double layer a capacitive character. Such a simplifying assumption causes a modelling error and influences all parameters of the system. The problem is analysed for several characteristic examples of an electrode system, where a simple electrode reaction takes place. The two most frequently used definitions of CPE are applied. One of them should be rejected, as intrinsically erroneous. An electrode with a double layer of CPE character can never be an `ideally polarizable electrode'. The conclusions can be qualitatively applied to all systems with an interface revealing CPE behaviour.     

Common epileptic pathway in amygdaloid bicuculline and electrical kindling demonstrated by transferability

The transferability between amygdaloid bicuculline kindling and electrical kindling was studied in rats. Electrically kindled animals exhibited stage 5 generalized seizures on the first injection of bicuculline, in contrast to the 3–7 injections required in controls. Similarly, bicuculline-kindled animals reached stage 5 after significantly fewer electrical stimulations than controls; two-thirds of the bicuculline-kindled animals began in stage 1 but skipped stages 3 and 4 on their way to stage 5. These data indicate that a common generalization mechanism exists in both types of kindling, but the process of progression from local seizure to generalized seizure may be immature in bicuculline kindling.     

电阻抗法测定精子浓度

①目的 建立电阻抗法测定精子浓度的实验方法。②方法 精液标本直接经溶血素作用，溶解精子尾部及卵磷脂小体，然后采用 Ｆ－８００血细胞分析仪模拟血小板检测步骤测定精子浓度。③结果 精子体积直方图分布主要集中于２～２０ｆｌ。测定高、中、低精子浓度的变异系数分别为２．９％、４．４％、９．０％。精子浪度在（１～２３７）×１０９／Ｌ范围内显示良好的线性（ｒ＝０．９９７）。６６例精液标本用本法（Ｙ）测定结果与 Ｍａｋｌｅｒ精子计算盘法（Ｘ）测定结果比较，显示两种方法相关性良好（Ｙ＝１.０７ Ｘ＋１．９６，ｒ＝０．９９３），两组结果平均误差不超过 １０％。④结论 本法精密度高，简便实用，适于常规实验室开展。     

Optimal parameters for effective electrical stimulation of the anal sphincters in a child with fecal incontinence: preliminary report

The purpose of the present study was to examine the optimal parameters for electrical stimulation of the anal sphincters to improve fecal incontinence in a child after abdominoperineal anorectoplasty for imperforate anus. A pair of coiled-wire electrodes was implanted bilaterally into the deep external sphincter, and alternating bidirectional, biphasic pulses of regulated current were applied. Anal pressure increased in response to an increase in pulse amplitude, width, or frequency, but fell again rapidly when the pulse frequency was higher than 10 Hz. Assuming that an anal pressure of 30 mmHg was necessary to improve anal continence and that tissue damage caused by electrical stimulation and muscle fatigue should be minimized, pulse frequency of 5 Hz and pulse width of 0.1–0.3 ms were determined to be desirable parameters for effective electrical anal sphincter stimulation.     

Implications of the dielectrical behaviour of human blood for continuous online measurement of haematocrit

A study was designed to explore the possibility of detecting the haematocrit of blood by means of admittance measurements. The admittance and phase angle of blood kept in a measuring cell were determined at various frequencies between 60 kHz and 24 MHz. A reliable and accurate estimation of haematocrit was obtained in two ways. First, low-frequency admittance, high-frequency admittance and a factor x, which was the conductive percentage of cell content, were used. Secondly, the maximum phase angle was used. Both methods can be applied to obtain continuous on-line information about haematocrit for blood volume control during haemodialysis.     

电刺激后颅窝治疗脑血管病的初步临床评价

为观察电刺激小脑顶核（ＦＮ）治疗脑血管病的临床疗效，探讨其可能治疗机制．１００例脑血管病患者（经ＣＴ或ＭＲＩ证实）均接受常规治疗，其中５０例用脑循环功能治疗仪经皮电刺激后颅窝，另５０例神经功能缺损评分与匹配的对照患者不接受该治疗，于治疗１０天后进行评分。治疗１０天后，该治疗对不同病情程度患者都有促进神经功能恢复的作用，接受治疗者与不接受者具有显著差异（Ｐ＜０．００１）。应用脑循环功能治疗仪电刺激小脑顶核对脑血管病患者有促进神经功能恢复的作用。     

Semi-quantitative electromyography as a predictor of nerve transfer outcome

ObjectivesEvaluate correlation between donor nerve semi-quantitative electromyography (sqEMG) and strength outcome in nerve transfer surgery.MethodsRetrospective review of pre-operative donor nerve semi-quantitative neurophysiology and post-operative recipient muscle force after at least one-year follow-up. The semi-quantitative technique is the average motor unit number estimate associated with needle recorded interference patterns in the donor muscle (IP-AMUNE), which was correlated with hand-held manometry, standardized as a percent of the contralateral arm, using multivariable linear regression with backward selection.ResultsTwenty-eight nerve transfer cases were included. The correlation between the donor nerve IP-AMUNE and the recipient muscle strength was moderate to strong and highly significant (r = 0.67, p < 0.001). Medical Research Council (MRC) grading did not predict strength (p > 0.54).ConclusionsIP-AMUNE is a good predictor of strength after nerve transfer surgery and should be considered in the evaluation and planning of patients undergoing nerve transfer to aid in donor nerve selection.SignificanceIP-AMUNE may significantly benefit those undergoing nerve transfer surgery for the restoration of movement.     

Photosensitive Epilepsies and Photoconvulsive Responses in Arabs

The occurrence of photosensitivity (PS) was examined in 327 Arabs greater than or equal to 15 years of age with epilepsy by intermittent photic stimulation (IPS). A control group of 192 nonepileptic Arabs greater than or equal to 15 years of age were also examined by IPS. Of the epileptic patients, 24 (7.3%) were photosensitive, an incidence comparable to that in whites in contradistinction to the reported rarity among African blacks. This finding indicates that environmental factors, particularly excessive sunshine, does not appear to influence the occurrence of PS among epileptic patients. The occurrence of PS among epileptic patients may depend more strongly on the presence of an epileptic syndrome known to have association with PS.     

心房颤动离子通道重构的研究进展

心房颤动是临床上最常见的心律失常,目前国内外学者研究认为,心房电重构在心房颤动发生和维持中起主要作用,而心房电重构主要由离子通道重构引起,本文对此进行综述。     

大容量人天然噬菌体单链抗体库的构建

目的：构建大容量和具有良好多样性的人天然噬菌体单链抗体库。方法：从人外周血分离淋巴细胞，提取mRNA后用RT—PCR技术采用新设计的引物扩增VH和VL基因片段，两者分别与Linker连接后，采用改进的重叠延伸PCR法将VH基因和VL基因连接成人单链抗体（scFv）基因（VH—Linker—VL片段），继而连接到噬菌粒载体pCANTAB5E中，连接产物通过电转化方法转入大肠杆菌TG1，构建噬菌体scFv抗体库。结果：所有VH、VL亚类基因都得到了扩增和有效的连接．经电转化E.coli TG1和噬菌体的超感染，构建了总库容达到了6×10^8的单链抗体库。结论：成功地构建了一个多样性良好的人源天然噬菌体抗体库，可用于制备具有应用前景的人源抗体。