Intracortical inhibition of lower limb motor-evoked potentials after paired transcranial magnetic stimulation

The aim of the present study was to determine the characteristics of intracortical inhibition in the motor cortex areas representing lower limb muscles using paired transcranial magnetic (TMS) and transcranial electrical stimulation (TES) in healthy subjects. In the first paradigm (n=8), paired magnetic stimuli were delivered through a double cone coil and motor evoked potentials (MEPs) were recorded from quadriceps (Q) and tibialis anterior (TA) muscles during relaxation. The conditioning stimulus strength was 5% of the maximum stimulator output below the threshold MEP evoked during weak voluntary contraction of TA (33±5%). The test stimulus (67±2%) was 10% of the stimulator output above the MEP threshold in the relaxed TA. Interstimulus intervals (ISIs) from 1–15 ms were examined. Conditioned TA MEPs were significantly suppressed (P<0.01) at ISIs of less than 5 ms (relative amplitude from 20–50% of the control). TA MEPs tended to be only slightly facilitated at 9-ms and 10-ms ISIs. The degree of MEP suppression was not different between right and left TA muscles despite the significant difference in size of the control responses (P<0.001). Also, conditioned MEPs were not significantly different between Q and TA. The time course of TA MEP suppression, using electrical test stimuli, was similar to that found using TMS. In the second paradigm (n=2), the suppression of TA MEPs at 2, 3, and 4 ms ISIs was examined at three conditioning intensities with the test stimulation kept constant. For the pooled 2- to 4-ms ISI data, relative amplitudes were 34±6%, 61±5%, and 98±9% for conditioning intensities of 0.95, 0.90, and 0.85× active threshold, respectively (P<0.01). In conclusion, the suppression of lower limb MEPs following paired TMS showed similar characteristics to the intracortical inhibition previously described for the hand motor area. Received: 21 June 1996 / Accepted: 23 May 1997     

Clinical and electroencephalographic changes in MMP+-induced parkinsonian syndrome in rats

Laboratory of General Pathology of the Nervous System, Research Institute of General Pathology and Pathological Physiology, Academy of Medical Sciences of the USSR. Laboratory of Psychopharmacology and Group for Synthesis of Physiologically Active Compounds, Research Institute of Pharmacology, Academy of Medical Sciences of the USSR, Moscow. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 107, No. 2, pp. 147–150, February, 1989.     

Dielectric behavior of pulmonary edema induced in the rat lung

The dielectric properties (conductivity, kappa and relative permittivity, epsilon) of excised rat lung are modified by lung air and water content. The measurements of these quantities were made over the frequency range of 10 kHz to 100 MHz with an open-ended coaxial probe. The following relationships were analyzed in an oleic acid-induced pulmonary edema model using 18 animals: the spectra of kappa, epsilon and the loss tangent as a function of lung air and water content. Secondly, an isolated-perfused lung system was produced to induce a gradual increase in lung water. The time course of kappa, epsilon and the loss tangent for one excised lung was analyzed. The principal findings were: (i) a decrease in kappa and epsilon with increasing air content, (ii) an increase in kappa and epsilon with increasing water content, and (iii) a good correlation between lung water content and maximum loss tangent that was insensitive to changes in air content. We conclude that this technique could provide a quantitative assessment of lung water during pulmonary edema formation.     

Fear of Movement/Injury in the General Population: Factor Structure and Psychometric Properties of an Adapted Version of the Tampa Scale for Kinesiophobia

In recent years, several studies have pointed out the importance of pain-related fear in the development and maintenance of chronic pain. An important instrument for measuring pain-related fear in the context of low back pain is the Tampa Scale for Kinesiophobia (TSK). Recently, a version of this questionnaire has been developed for administration among the general population (TSK-G). To determine the factor structure of the TSK-G, data from a random sample of the Dutch general population were studied separately for people who had had back complaints in the previous year, and people who had been without back complaints. For both groups the TSK-G appeared to consist of one, internally consistent, factor of 12 items. The one-factor TSK-G also appeared valid after comparison with scores on measures of catastrophizing and general health status.     

Novel Semi‐Fluorinated Poly(ether imide)s Derived From 4‐(p‐Aminophenoxy)‐3‐trifluoromethyl‐4′‐aminobiphenyl

An unsymmetrical diamine monomer 4‐(p‐aminophenoxy)‐3‐trifluoromethyl‐4′‐aminobiphenyl has been synthesized successfully. This monomer leads to the synthesis of different novel poly(ether imide)s when reacted with different dianhydrides like pyromellatic dianhydride (PMDA), benzophenone tetracarboxylic acid dianhydride (BTDA), 2,2‐bis(3,4‐dicarboxyphenyl) hexafluoropropane (6FDA), and oxy diphthalic anhydride (ODA). The poly(ether imide) prepared from this monomer on reaction with 6FDA is soluble in several organic solvents such as N‐methylpyrolidinone (NMP), dimethylformamide (DMF), N,N‐dimethylacetamide (DMAc), tetrahydrofuran (THF), and CHCl₃. The poly(ether imide)s prepared from BTDA and ODA are soluble in NMP, DMF, and DMAc but not in THF or CHCl₃, whereas the polymer prepared from PMDA is soluble only in NMP. The water uptake value for these poly(ether imide) films is very low (0.2–0.5%), and exhibited low dielectric constants (2.81 at 1 MHz). The polymers exhibited high thermal stability up to 532 °C in air for 5% weight loss, and high glass transition temperatures up to 288 °C. The polymer exhibited high tensile strength up to 135 MPa, modulus 3.2 GPa, and elongation at break up to 25%, depending on the exact polymer structure.

The structure of the poly(ether imide) synthesised from 4‐(p‐aminophenoxy)‐3‐trifluoromethyl‐4′‐aminobiphenyl and 2,2‐bis(3,4‐dicarboxyphenyl) hexafluoropropane. This polymer was soluble in many organic solvents.     

Pretherapeutic flow cytometric DNA investigations in radiotherapy patients with maxillo-facial carcinomas

In order to analyze the possible meaning of cellular DNA content and cell cycle phases for the radiosensitivity and the prognosis of human malignant tumors, flow cytometric measurements have been performed in biopsies of 131 patients with histologically proven squamous cell carcinomas of the maxillo-facial region. In two-thirds of the patients (88/131; 67%), aneuploid tumor cell lines have been found, only 33% (43/131) had a diploid DNA distribution pattern. The average DNA index (DI) of the aneuploid carcinomas was 3.4 +/- 0.6 (normal nonmalignant tissue DI = 2.0). The frequency of S-phase cells, which represents the "proliferative activity", was between 4.8 and 63.2%, regardless of the ploidy stages. The aneuploid carcinomas had about twice as many S-phase cells (mean 23.7 +/- 11.8%) than diploid tumors (mean 12.7 +/- 4.8%). Mean survival for patients with diploid carcinoma and aneuploid carcinoma was 12 and 9.5 months, respectively. Concerning the relationship of S-phase frequency and survival times in our material there was a high negative statistical correlation (Spearman-Rank test) in patients with diploid carcinomas. A high S-phase fraction resulted in short survival times. No correlation was found in the aneuploid carcinomas: patients with tumors in high S-phase values in their biopsies showed no difference in prognosis in comparison to tumors with lower S-phase fractions.     

一种复合微生物菌肥对穿心莲生长、品质及土壤性质的影响

目的：研究一种微生物复合菌肥对穿心莲生长、品质及土壤性质的影响,旨在为穿心莲栽培生产中微生物复合菌肥的应用提供依据。方法：通过盆栽的共5个处理试验,CK（不施肥）组、A处理（施化肥）组、B处理（施微生物菌肥,施用量为2.5 g·kg-1土）组、C处理（施微生物菌肥,施用量为7.5 g·kg-1土）组、D处理（施微生物菌肥,施用量为12.5 g·kg-1土）组,研究一种复合微生物菌肥对穿心莲的农艺性状、有效成分含量及根际土壤细菌、放线菌、真菌的数量和土壤理化性质的影响。结果：施加一定量的复合微生物菌肥,穿心莲的株高、叶片数、叶面积、地上部、地下部鲜重较CK组和A处理组显著升高,不同生长期有差异。复合微生物菌肥对穿心莲内酯、脱水穿心莲内酯、新穿心莲内酯及14-去氧穿心莲内酯含量影响有差异,与CK组、A处理组比较,C处理组的穿心莲内酯分别明显升高26.13%、13.23%(P<0.05);新穿心莲内酯的含量随微生物菌肥施加量的增加而增加,在D处理组下的效应最显著,与CK组、A处理组比较,分别明显升高9.06%、50.33%(P<0.05);B处理组的14-去氧穿心莲内酯较A处理组...     

膈神经传导时间的测定及其影响因素

目的:探讨用经皮电刺激双侧膈神经法测定膈神经传导时间(ＰＮＣＴ)的正常值及其影响因素。方法:对１３例肺功能正常者和７例慢性阻塞性肺疾病(ＣＯＰＤ)患者用经皮电刺激双侧膈神经法测定ＰＮＣＴ。结果:①１３例肺功能正常者左、右侧ＰＮＣＴ分别为:(７．０２±０．８６)ｍｓ和(８．１３ ±０．９１)ｍｓ,右侧显著长于左侧(Ｐ＜０．００１);②７例ＣＯＰＤ患者左、右侧ＰＮＣＴ分别为:(７．１９ ±０．７２)ｍｓ和(８．０８ ±０．８４)ｍｓ,右侧同样长于左侧(Ｐ＜０．０５);③肺功能正常组ＣＯＰＤ组间,双侧ＰＮＣＴ均没有统计学上的差异(双侧Ｐ＞０．０５);④ＰＮＣＴ与年龄和身高呈直线相关,而与体重无显著性相关;⑤ＰＮＣＴ不随电流刺激量增高而变化。结论;左、右侧ＰＮＣＴ的正常值分别为:(７．０２ ± ０．８６)ｍｓ和(８．１３ ±０．９１)ｍｓ;ＣＯＰＤ肺功能异常者的ＰＮＣＴ基本无变化;ＰＮＣＴ与受试者的身高和年龄相关,不受电刺激强度的影响。     

聚吡咯／聚合物固体电解质双层复合膜研究

在聚合物固体电解质（聚乙二醇不饱和聚酯网络－LiClO4)中进行吡咯聚合原位制得了聚吡咯／聚合物固体电解质双层复合膜。用扫描电镜观察复合膜的界面结构,用循环伏安和交流阻抗法研究了复合膜的电化学杂脱掺杂性能。结果表明,聚吡咯／聚合物固体电解质双层复合膜具有相互穿插渗透的固／固密接界面结构,这种界面结构改善了聚吡咯和聚俣物固体电解质间的界面接触,提高了聚吡咯在聚俣物固体电解质中的电化学掺杂脱掺杂性能。