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51.
Intraperitoneal injection of free valproic acid (VPA) suppressed amygdaloid-kindled seizure 1 h after injection in rats, but had no effect at 24 h. VPA entrapped in positively charged liposomes showed a prolonged anticonvulsant effect lasting for 2 days, while the effect evaluated at 1 h was not different from that with free VPA. VPA entrapped in negatively charged liposomes exerted a significantly stronger effect at 1 h than did free VPA, while it had no significant effect at 24 h. These results suggest that surface charges on liposomes play an important role in modifying the anticonvulsant effect of VPA.  相似文献   
52.
新生大鼠反复惊厥对NMDA受体表达的长期影响   总被引:6,自引:0,他引:6  
目的:研究反复惊厥对大鼠脑内N-甲基-D-天门冬氨酸(NMDA)受体表达,以及成年期认知功能和惊厥阈的长期影响。方法:生后6d(用P6表示,下同)的Wistar大鼠随机分成两组,每组6只,惊厥组每日吸入三氟乙醚诱导惊厥发作1次,每次持续30min,连续6d;对照组同样操作但不吸入三氟乙醚。两组大鼠于P60-P65行Morris水迷宫实验,检测大鼠的学习记忆功能。于P75时给予大鼠腹腔注射戊四唑(PTZ)测定大鼠的惊厥阈。随即断头处死大鼠,分离大脑皮质和海马,匀浆提取细胞膜蛋白,应用免疫印记法测定NMDA受体亚基l(NRl)和NR2A-2D表达的变化。结果:从P6l至P65,两组大鼠寻找平台时间均逐渐缩短,惊厥组大鼠在P65的平均寻找平台时间较对照组显著延长。惊厥组大鼠注射PTZ后发生惊厥的潜伏期与对照组比较差异无显著性。在大脑皮层,惊厥组大鼠较对照组NRl和NR2B表达水平明显下调,在海马这两种亚基表达水平无明显改变,在大脑皮层和海马区,惊厥组较对照组NR2A表达水平明显下调,NR2C表达水平明显上调。两组在皮层和海马均无NR2D表达。结论;新生大鼠反复惊厥可导致远期认知障碍,同时伴有NMDA受体的数量和结构上的长期改变,NMDA受体表达的这种改变可能在发育期惊厥导致的脑长期认知功能损害中起重要作用。  相似文献   
53.
目的 分析总结腰椎间盘突出症手术后复发的原因及治疗方法。方法 腰椎间盘突出症手术后复发的范围限定于临床症状、体征及影像学证实为受累神经根与第一次手术的节段相同。回顾1990年~2001年收治的资料完整的病例38例。总结造成复发的原因,分析造成这些原因的因素以及防范措施,并提出治疗方案。结果 复发的原因为髓核再突出20例(占52.7%)、疤痕压迫5例(占13.1%)、硬脊膜及神经根四周粘连5例(占13.1%)、腰椎失稳4例(占l0.5%)、神经根管、侧隐窝狭窄4例(占l0.5%),其中经保守治疗和手术治疗分别为2l例(占55.3%)和17例(占47.7%),治疗优良率92%。结论 腰椎间盘突出症术后复发的主要原因为髓核再突出。复发后经中西医结合治疗能取得满意疗效,治疗上首先应采用保守治疗。  相似文献   
54.
Optimal surgery remains the mainstay of best outcome for rectal cancer. The demonstration, during the 3rd Annual Pelican Surgical Workshop Symposium, of an abdomino‐perineal excision (APE) performed in the ‘Berlin position’, further added to the debate on optimal surgical technique. Much interest was created at the 1st Pelican symposium with the demonstration, by the Swedish surgeon Dr Torbjorn Holm, of a prone APE and the delivery of a ‘cylindrical’ specimen and the potential to reduce local recurrence using this approach. The high rates of local recurrence following APE and the discussions as to optimal technique have led to the development of a proposed MERCURY Study Group study to assess the benefit of a radical APE, with careful assessment of the impact that this operation may have on morbidity. A German study has also been proposed adopting the UK's multidisciplinary team approach. It aims at targeting preoperative chemoradiotherapy at those patients in whom a radical APE or total mesorectal excision is likely to result in an involved surgical resection margin. In this article we review the evidence for improving the surgical technique for low rectal cancer. We believe improvements may be best achieved through continued European prospective, multi‐centre, multidisciplinary studies.  相似文献   
55.
影响原发性肝癌根治术后近期和远期复发的临床病理因素   总被引:2,自引:0,他引:2  
目的 :探讨根治性肝癌术后近期和远期复发因素 ,以期对高复发倾向人群抗复发提出针对性对策。方法 :回顾分析 1994年 5月~ 1998年 1月 16 2例根治性肝癌切除病例的临床资料 ,以影像学发现肿瘤复发及患者死亡或末次随访日期为截点确定无瘤生存时间 ,将术后复发病人分为近期复发 (≤ 2年 )、远期复发 (>2年 )及未复发 3组 ,确定复发危险因素。结果 :本组术后 1、 3、 5年无瘤生存率分别为 6 7. 1、 4 4 . 7及 2 5 . 5 %。与肿瘤近期复发相关因素为发现方式、肿瘤大小、血管癌栓、INM分期 ;与后期复发相关因素为有无肝硬化及其类型、肝功Child -Pugh分级和有无子瘤。结论 :根治性肝癌切除术后近期和远期复发的临床病理因素不同 ,及早发现小肝癌是预防近期复发的关键 ,兼顾术前肝功能可以对远期复发有预测作用  相似文献   
56.
The voltage-sensitive dye diO-C2-5 was used to produce an in vivo map of the membrane potential in two types of seizures. Mild limbic seizures were induced in rats with kainic acid; clonic convulsive seizures were induced with bicuculline. Kainic acid animals showed various levels of neural depolarization during their seizures in limbic, thalamic, cortical, and brainstem sites. The bicuculline animals showed uniformly greater levels of neural depolarization during their seizures. The magnitude of these changes relative to controls varied across seizure models and reflected the different underlying neural mechanisms for each model. The ability of the technique to capture local electrical events provides a new tool in which to explore brain activity.  相似文献   
57.
Summary Changes occurring in serotonin neurons during hyperthermia-induced convulsions were examined by means of a modified immunohistochemical method. All mice (8–12 weeks of age) exposed to the temperature of 50°C had convulsions, showing a generalized tonic and/or clonic pattern. Immediately after the convulsions, the animals were perfused transcardially with a fixative. A significant reduction in serotonin immunoreactivity was observed in the neostratum (caudate-putamen complex) of the mice which had hyperthermia-induced seizures, while the serotonin immunoreactivity remained unchanged in the neocortex and paleostriatum. These results suggest that serotonin may be an important mediator in the mechanism of hyperthermia-induced convulsions or that the susceptibility of serotonin neurons to a convulsive state is greatest in the neostriatum.Supported in part by Grant No. 86-05 from the National Center for Nervous, Mental and Muscular Disorders (NCNMMD) of the Ministry of Health and Welfare and Grant No. 62770677 from the Ministry of Education, Science and Culture, Japan  相似文献   
58.
OBJECTIVE: Circumferential resection margin (CRM) involvement has been correlated with a high risk of developing local recurrence. The aim of this study was to examine the prognostic significance of the CRM involvement after curative resection of rectal cancer in patients treated with preoperative radiotherapy and postoperative chemotherapy where indicated. METHOD: All patients with rectal cancer treated in a regional central unit from 1996 to 2004 were identified. A surgical resection was performed on 257 patients, and in 229 of these this was assessed as potentially curative. The CRM was examined in all patients. A CRM of < or = 1 mm was considered positive. RESULTS: A positive margin was seen in 19 (8%) patients. At a median follow up of 40 months, only four (1.7%) patients had developed local recurrence, one of whom had a positive CRM. In the four patients the tumour was 5 cm or less from the anal verge. There were no significant differences regarding local recurrence and survival between CRM positive and negative tumours. CONCLUSION: Rectal cancer managed by combined radiochemotherapy and surgery resulted in a low positive CRM rate and a low local recurrence rate. An involved CRM was not a predictor of local recurrence.  相似文献   
59.
大肠癌肝转移射频消融后局部复发影响因素的分析   总被引:1,自引:0,他引:1  
目的 探讨射频消融(radiofrequency ablation,RFA)治疗大肠癌肝转移后局部肿瘤复发的风险因素。方法 回顾性研究213例347个肿瘤实施RFA治疗后局部复发的临床资料,对可能影响RFA局部治疗效果的临床因素进行统计学处理。结果 175例(82.2%)298个肿瘤(85.9%)得到CT或MRI随访资料。大肠癌肝转移灶RFA后肿瘤局部复发率为36.9%(110/298),局部复发的平均时间为16.4月(2~57个月)。单因素分析显示肝脏转移灶的部位、大小和射频针类型与肿瘤射频后的局部复发相关(P值分别为P=0.000,P=0.021和P=0.026),但Cox多因素分析则显示只有瘤大小和转移灶部位是大肠癌肝转移射频消融后局部复发的独立预后因素(χ^2=8.522,P=0.000;χ^2=1.321,P=0.022)。结论 肝脏肿瘤的大小和部位是RFA治疗效果的独立影响因素,正确的电极选择和布针是获得肿瘤完全坏死的关键。  相似文献   
60.
After laparoscopic repair of ventral or incisional hernias, the recurrence rates reported are around 4%. Different mechanisms for the recurrences have been identified. We report two cases in which the patients were operated on laparoscopically for recurrence after laparoscopic ventral hernia repair. In both cases, the site of the recurrent hernia was situated at the transfascial fixation sutures. Patients were treated by laparoscopy with a larger intraperitoneal mesh covering the new hernia and the old mesh.  相似文献   
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