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Szilassy  De´nes  Sala´nki  Katalin  Bala´zs  Ervin 《Virus genes》1999,18(3):221-227
Infectious full-length cDNA clones from the genomic RNAs of a subgroup II cucumber mosaic cucumovirus strain (Trk7) were obtained. Sequence analysis of the whole genome revealed strong homology (99%) to the genome of Q-CMV, the only subgroup II strain whose entire genomic nucleotide sequence had been available in the database, and an overall 75% homology to those of subgroup I strains. We provide sequence comparisons of different parts of 1a, 2a and 2b proteins of Cucumovirus species, and propose phylogenetic trees based on these protein sequences.  相似文献   
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After partial denervation, the remaining motor units (MUs) of adult fast extensor digitorum longus muscle (EDL) expand their peripheral field. The time course of this event was studied using tension measurement and recordings of electromyographic (EMG) activity. The results show that after section of the L4 spinal nerve, when only 5.3 ± 0.63 of the 40 MUs normally supplying EDL muscle remain, the force of individual motor units starts to increase between the 1st and 2nd week after the operation and continues to do so for a further week. The drastic reduction of the number of motoneurones supplying the fast EDL leads to an increase in activity of the remaining MUs. In the 1st week after partial denervation, there was a sharp increase in the EMG activity of remaining motor units. During the next 12 days, this increase became less marked, but EMG activity remained nevertheless significantly higher than that of the unoperated EDL muscle. Many MUs became tonically active during posture. The EMG activity pattern during locomotion was also altered, so that the burst duration was positively correlated with the step cycle duration. Moreover, shortly after partial denervation, the interlimb coordination was disturbed but returned to its original symmetrical use 1–2 weeks later. Received: 17 September 1996 / Accepted: 3 November 1997  相似文献   
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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  相似文献   
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卵巢肿瘤增殖细胞核抗原的表达及意义   总被引:3,自引:0,他引:3  
袁碧波  刘姝华 《天津医药》1999,27(12):731-733
目的:研究增殖细胞核抗原(PCNA)在卵巢肿瘤中的表达及意义。方法:应用免疫组化ABC法检测133例卵巢肿瘤和12例正常卵巢组织PCNA的表达。结果:卵巢肿瘤与正常卵巢组织的PCNA表达有显著性差异。良性、交界性、恶性组PCNA表达呈上升趋势(P〈0.05)。病理分类上皮性组PCNA表达显著高于非上皮性组(P〈0.05)。在上皮性组中,中、低分化组PCNA表达高于高分化组,晚期表达高于早期(P〈0  相似文献   
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阿霉素脂质体淋巴管灌注的靶向效果   总被引:2,自引:0,他引:2  
目的:探讨阿霉素脂质体经淋巴管灌注后的体内动力学过程以及靶向效果。方法:将60只家兔随机分为阿霉素脂质体和阿霉素水溶液两组,从家兔足背淋巴管给药,采用高效液相色谱(HPLC)法检测给药后各时点外周血及腹膜后淋巴结中阿霉素药物浓度,并将摘取的淋巴结作病理检查。结果:水溶液组腹膜后淋巴结阿霉素峰浓度(Cmax)为46.81μg/g,药时曲线下面积(AUC)为31.86μg/dayg-1;而脂质体组阿霉素峰浓度为91.23μg/g,AUC为138.34μg/dayg-1。在外周血中脂质体组的峰浓度只有水溶液组的1/5。淋巴结病理检查结果表明,脂质体组的水肿、坏死、纤维化较水溶液组明显,而心肌病理反应较轻或不存在。结论:脂质体对淋巴结具有高度靶向性,阿霉素脂质体淋巴管灌注有可能成为治疗淋巴结转移的有效且副作用少的新方法。  相似文献   
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目的研究环磷酸腺苷葡胺(心先安,McAMP)围术期对心肌缺血老年病人心肌梗死的预防和治疗作用。方法40例有心肌缺血基础的老年病人随机分为治疗组和对照组,每组各20例。治疗组在麻醉诱导前10min静脉注射心先安20mg,随后160mg加入100ml0.9%氯化钠注射液中持续缓慢静脉滴注;对照组静脉滴注0.9%氯化钠注射液。术中纪录心电图各导联ST段水平、MAP和HR,并计算HR与SBP的乘积(RPP);同时抽取外周静脉血检测术前、术毕、术后24h血清心肌肌钙蛋白I(cTnI)水平。结果术中对照组出现明显的ST段下降和RPP升高,与治疗组比较差异有统计学意义(P<0.05);治疗组术后cTnI水平的升高程度较对照组为低(P<0.05)。术后对照组有2例出现灶性心肌梗死。结论心先安预防和治疗老年患者围术期心肌缺血、心肌梗死具有较好的作用。  相似文献   
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Background:Myasthenia gravis (MG) is an archetypal autoimmune disorder. The conventional treatments for this disease are drugs, plasma exchange, surgical, and so on. However, this disease is difficult to cure. A mass of studies revealed that the external treatment of traditional Chinese medicine (TCM) for MG is a safe and economical approach. The present study conducted a meta-analysis to compare TCM external treatment combined with modern medicine with modern medicine for MG, in order to determine which TCM external treatment intervention has the best relative efficacy, safety, and provide the best evidence for clinical practice.Methods:PubMed, Cochrane Library, EMBASE, Web of Science, Springer, China National Knowledge Infrastructure (CNKI), Wan-fang database, VIP Chinese Science and Technique Journals Database, the Chinese Bio Medical Database (CBM), and Baidu Scholar were searched. The time of publication was limited from inception to February 28, 2021. Two reviewers independently searched for the selected articles and extract the data. The RevMan V.5.3 statistical software (Cochrane Collaboration) and Stata V.16.0 software were used to conduct the meta-analysis.Results:The results of the systematic review and meta-analysis will be published in a peer-reviewed journal.Conclusion:The present study provides a protocol that can be used in the systematic review and meta-analysis, with the intent to inform professionals on the external treatment of TCM for MG. These would lead to investigations on the use of the most external treatment of TCM for MG.Trial registration number:INPLASY202110083  相似文献   
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