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21.
Neural activity was recorded from the median nerve of a monkey during grasping and lifting, using a chronically implanted cuff electrode. At the onset of lifting, there was an initial dynamic response during which the intensity of the neural signal increased rapidly. This neural response attained its peak value well before the displacement, the load force or the grip force. The time course and peak of the rectified, integrated neurogram were best correlated with the rate of change of grip force. The neural activity declined exponentially to a steady value following the initial peak. During steady holding the mean amplitude of the neurogram was best correlated with the mean grip force. At the end of the holding phase there was a short burst of neural activity as the monkey relaxed the grip force and released the object. During some blocks of trials pulse perturbations were applied to the object. When the monkey did not increase the grip force in advance of the perturbation, the perturbation produced a relatively large displacement of the object and a burst of neural activity whose onset coincided with the onset of displacement. When the monkey anticipated the perturbation by increasing the grip force during the holding period preceding the perturbation, the perturbation produced a relatively small displacement and relatively little increase in neural activity.  相似文献   
22.
OBJECTIVE: Using meta-analytical techniques the present study evaluated differences in short-term and long-term outcomes of adult patients with colonic Crohn's disease who underwent either colectomy with ileorectal anastomosis (IRA) or segmental colectomy (SC). METHODS: Comparative studies published between 1988 and 2002, of subtotal/total colectomy and ileorectal anastomosis vs segmental colectomy, were used. The study end points included were surgical and overall recurrence, time to recurrence, postoperative morbidity and incidence of permanent stoma. Random and fixed-effect meta-analytical models were used to evaluate the study outcomes. Sensitivity analysis, funnel plot and meta-regressive techniques were carried out to explain the heterogeneity and selection bias between the studies. RESULTS: Six studies, consisting of a total of 488 patients (223 IRA and 265 SC) were included. Analysis of the data suggested that there was no significant difference between IRA and SC in recurrence of Crohn's disease. Time to recurrence was longer in the IRA group by 4.4 years (95% CI: 3.1-5.8), P < 0.001. There was no difference between the incidence of postoperative complications (OR = 1.4., 95% CI 0.16-12.74) or the need for a permanent stoma between the two groups (OR = 2.75, 95% CI 0.78-9.71). Patients with two or more colonic segments involved were associated with lower re-operation rate in the IRA group, a difference which did not reach statistical significance (P = 0.177). CONCLUSIONS: Both procedures were equally effective as treatment options for colonic Crohn's disease however, patients in the SC group exhibited recurrence earlier than those in the IRA group. The choice of operation is dependent on the extent of colonic disease, with a trend towards better outcomes with IRA for two or more colonic segments involved. Since no prospective randomised study has been undertaken, a clear view about which approach is more suitable for localised colonic Crohn's disease cannot be obtained.  相似文献   
23.
周围神经端侧动脉套接后神经再生的研究   总被引:6,自引:2,他引:4  
目的研究周围神经端侧动脉套接后神经再生的可能性及其特点. 方法取SD大鼠75只,在股骨中下段切断腓神经,将近断端逆转90度包埋于肌肉中.随机分为5组.A组:将截取的左颈总动脉套接于右侧正常胫神经侧方与腓总神经远端2 mm距离之间,缝合部胫神经外膜不予切除;B组:在胫神经套接部外膜开窗1.0 mm;C组:腓总神经切断14天后再予动脉套接,余同B组;D组:同B组,且于动脉套接部注入神经生长因子(neural growth factor, NGF)1 ml;E组:将腓总神经远端以端侧缝合形式直接缝合于胫神经的一侧,外膜开窗1.0 mm.术后4、8和12周分别行组织学、电镜和神经纤维计数等检查. 结果 4周时C、D及E组周边区域有神经纤维轴突和髓鞘再生,A组则无神经纤维生长; 8周时C、D及E组再生神经纤维较B组多,E组神经纤维较C、D组多,差异有统计学意义(P<0.05); 12周时C、D及E组神经纤维多于B组,差异有统计学意义(P<0.05);C组及D组有较丰富的神经再生,与神经端侧直接吻合的E组差异无统计学意义(P>0.05). 结论神经端侧2 mm距离动脉套接可作为修复周围神经损伤的一种可行方法.  相似文献   
24.
目的探讨第2足趾腓侧皮瓣移植的应用解剖及临床应用的适应证、手术方法和优缺点等。方法新鲜成人尸体足左、右各10只,经灌注、解剖、测量,了解皮瓣的血供范围和相关血管、神经的外径。临床应用17例修复手部皮肤缺损,了解皮瓣的成活及功能恢复情况。结果灌注剂可达整个第2足趾及相邻趾蹼,测得第2足趾跖趾关节处腓侧固有动脉、趾背静脉分别为(1.0±0.2)mm、(0.9±0.2)mm;临床应用17例移植皮瓣全部成活,手、足部均无感染。经半年以上随访,被修复手指外观、颜色接近正常,供足无疼痛和植皮破溃现象发生。结论第2足趾腓侧皮瓣血供可靠,口径适于吻合,质地好,适于手指皮肤确实的修复。  相似文献   
25.
2008年连云港市“手足口病”流行特征及病原学分型   总被引:1,自引:0,他引:1  
宋华 《职业与健康》2010,26(2):191-193
目的分析连云港市2008年手足口病的流行特征及病原学分型情况。方法应用流行病学方法对2008年该市的手足口病流行资料进行分析。结果依据疫情报告,实验室诊断病例45例,其中CoxA1638例,EV71型7例,其他肠道病毒0例。2008年该市临床报告手足口病例1067例,报告发病率为23.19/10万,比2007年上升442.34%,男女发病比为3.1∶1。发病年龄最小的为0岁组,最大的为8岁;0~5岁组,共计发病976例,占总发数的91.47%。发病数的构成以散居儿童最多,占76.66%。地区分布:全市各个区县均有手足口病病例报告,但城区的总体发病率高于县。结论连云港市手足口病发病率有上升趋势;控制传染源是有效防止该病流行的关键。  相似文献   
26.
邻近节指背筋膜(蒂)皮瓣修复手指皮肤软组织缺损   总被引:3,自引:3,他引:0  
目的报道应用手指缺损创面的邻近节指背筋膜(蒂)皮瓣修复手指皮肤组织缺损的方法。方法2004年10月~2006年8月,根据受区皮肤缺损的面积及形状,在供区设计斜形皮瓣修复手指皮肤软组织缺损创面共27例。结果皮瓣全部成活,术后3~20个月随访,皮瓣质地优良,外形与感觉功能恢复满意。结论手指缺损创面的邻近节指背筋膜(蒂)皮瓣手术操作简单、安全可靠,术后治疗、护理容易,外形与功能恢复良好,是手外科修复手指皮肤软组织缺损创面较为理想的方法,值得推广。  相似文献   
27.
对17例人工绝育后曾行输卵管复通手术失败病例,进行再次显微输卵管复通手术,经随访二年以上,宫内妊娠率41.18%(7/17)。手术后成功率与输卵管吻合部位有关,峡部与壶腹部吻合效果最差。作者指出再次显微输卵管吻合手术对由于原吻合部位闭锁病例有一定的价值。但需慎重考虑如何提高初次吻合术质量、防止术后粘连是十分重要。  相似文献   
28.
目的:探讨和研究治疗晚期面瘫的手术治疗,总结应用以足底内侧动静脉为蒂的(足母)展肌游离移植一期修复晚期面瘫40例效果和经验.方法:选取(足母)展肌为供肌,以足底内侧动静脉及其延续的胫后动静脉为血管蒂,以支配(足母)展肌神经及其延续的足底内侧神经和胫神经为神经蒂.(足母)展肌移植于患侧面部皮下,肌近断固定于口角,远端固定于耳前颧弓,血管神经蒂通过上唇皮下隧道与健侧面动静脉和面神经颊支吻合.结果:经随访一年以上,23例恢复了面部静态对称和理想的下面部随意和不随意运动;8例恢复了面部静态对称和部分下面部随意和不随意运动;9例仅恢复了面部静态对称.结论:(足母)展肌游离移植一期修复晚期面瘫具有疗效好、手术操作简便、肌肉大小适中、血管神经蒂走行位置恒定紧密伴行、血管神经蒂可切取较长、变跨面神经移植和肌肉移植的两期移植为一期移植等优点;而且,神经是血管化移植.  相似文献   
29.
Summary Purpose of this study was to evaluate the diagnostic value of a low field dedicated MRI system in hand and wrist imaging. All 308 exams of the hand and wrist, that were performed on a low-field dedicated MRI system (Artoscan, Esaote Biomedica, Italy) in our institution in 1996, and high-field MRI exams performed in addition as part of the diagnostic work-up, were evaluated and correlated to final operative (n = 64) and histologic (n = 12) reports. 90 % of all low-field MRI scans stated a diagnosis according to clinical suspicion. In 62 % the clinical question was answered, and in 26 % additional pathologies were identified. An MR-diagnosis completely different from the clinical suspicion was stated in 2 %. High field exams contributed additional information in 6 of 36 patients. In 3 patients a tumor was not shown completely in the limited field-of-view of the dedicated low-field MRI-system. Frequency-selective fat-suppression pulse sequences and a better spatial resolution were the reasons for the additional information obtained in the other three patients. Low-field dedicated MR-imaging is a valuable method in the extensive work-up of the hand and wrist. Osseous, ligamentous and tendinous pathologies are well depicted. Large or infiltrative tumors should be referred to a high-field system.   相似文献   
30.
慢性肾病患者常需要建立动静脉内瘘进行透析,常规间断缝合法吻合动静脉难度大、耗时长。为了缩短吻合时间,提高远期通畅率,进行了套叠粘接吻合法建立动静脉内瘘的实验研究,并将这一方法应用于透析患者建立动静脉内瘘的血管吻合。将动脉端套入静脉端,只需吻合两针,用医用胶封闭吻合口。经8个月观察,通畅率达100%,血流量均超过300ml/min。达到了透析需要。  相似文献   
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