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41.
The opioid transmitters enkephalin and dynorphin are known to regulate pallidal output and consequently cortical excitability. Indeed, abnormal basal ganglia opioid transmission has been reported in several involuntary movement disorders, including levodopa-induced dyskinesias in Parkinson's disease (PD), tardive dyskinesias/dystonia, Huntington's disease, and Tourette's syndrome. Moreover, a previous 11C-diprenorphine PET study investigating levodopa-induced dyskinesias found reduced opioid receptor availability in PD with but not without dyskinesias. We wished to investigate if a similar alteration in basal ganglia opioid binding was present in DYT1 primary torsion dystonia (PTD). Regional cerebral 11C-diprenorphine binding was investigated in 7 manifesting carriers of the DYT1 gene and 15 age-matched normal controls using a region-of-interest (ROI) approach and statistical parametric mapping (SPM). No difference in regional mean 11C-diprenorphine binding was found between DYT1-PTD and controls, and no correlation between the severity of dystonia and opioid binding was seen. We conclude that aberrant opioid transmission is unlikely to be present in DYT1-PTD and altered opioid transmission is not a common mechanism underlying all disorders of involuntary movement.  相似文献   
42.
丝裂霉素C及可调整缝线在小梁切除术中的应用   总被引:7,自引:2,他引:5  
目的 观察丝裂霉素C联合可调整缝线在青光眼小梁切除术中应用的效果。方法 我院近3年来小梁切除术98例,术中采用巩膜瓣下放置含丝裂霉素C棉片2~5分钟,然后迅速以平衡盐溶液冲洗,切除2mm×3mm包括小梁在内的深层角巩膜缘组织,并做虹膜根部切除,用10-0尼龙线间断缝合巩膜瓣2~4针后,再于巩膜瓣一侧或两侧作1条或2条型巩膜瓣缝合。形成前房。术后2周、3月、1年及1.5年检查视力、眼压、前房、滤过泡等情况。结果 术后眼压控制良好,Ⅰ、Ⅱ度浅前房发生率低,滤过泡形成良好,43%视力保持不变或改善,炎症反应轻,并发症少。结论 丝裂霉素C可提高小梁切除术后眼压控制率,联合可调整缝线,可有效控制术后滤过水平,减少术后并发症,提高成功率。  相似文献   
43.
Progressive myoclonic ataxia, also referred to as Ramsay Hunt syndrome, is characterized by a combination of myoclonus and cerebellar ataxia, infrequently accompanied by tonic-clonic seizures. Its differential diagnosis overlaps with progressive myoclonic epilepsy, a syndrome with myoclonus, tonic-clonic seizures, progressive ataxia and dementia. In patients with progressive myoclonic epilepsy, specific diseases can frequently be recognized, but the diagnostic yield in progressive myoclonic ataxia is much lower. We describe a patient who presented with multifocal myoclonus in his thirties and who later developed cerebellar ataxia and focal dystonia. His father was similarly affected. Genetic studies revealed a mutation in the protein kinase C gamma (PRKCG) gene, known to cause spinocerebellar ataxia type 14 (SCA-14). This case illustrates that both myoclonus and dystonia are part of the clinical spectrum in SCA-14 and that myoclonus can even be the presenting symptom. We suggest that SCA-14 should be considered in the differential diagnosis of progressive myoclonic ataxia.  相似文献   
44.
目的鉴定参与线虫衰老的神经内分泌调控的新基因。方法鉴于神经系统在衰老调控中的重要作用,通过寿命分析和脂褐质自发荧光的检测,从编码突触蛋白的遗传位点中筛选参与衰老调控的基因。我们还进一步检查了这些遗传位点相应的突变体的永久性幼虫形成情况,探讨它们是否可能受胰岛素样信号通路的调控。结果遗传位点 unc-10,syd-2,hlb-1,dlk-1,mkk-4,scd-2,snb-1,ric-4,nrx-1,unc-13,sbt-1,unc-64 可能参与线虫衰老的调控。而且在衰老的调控中,unc-10,syd-2,hlb-1,dlk-1,mkk-4,scd-2,snb-1,ric-4,nrx-1 的功能可能与unc-13,sbt-1,unc-64相反。肠道脂褐质自发荧光的检测进一步证明了筛选出的各基因对应突变体的长寿或短寿表型,是由减慢或缩短的组织衰老所致。在筛选出的基因中,syd-2,hlb-1,mkk-4,scd-2,snb-1,ric-4,unc-64 也参与了永久性幼虫形成的调控。另外,daf-2突变增强了syd-2和hlb-1的表达,降低了mkk-4,nrx-1,ric-4,sbt-1,rpm-1,unc-10,dlk-1,unc-13 的表达。daf-16突变提高了syd-2和 hlb-1 的表达,降低了mkk-4,nrx-1,sbt-1,rpm-1,unc-10,dlk-1,unc-13 的表达. 结论突触功能可能在个体寿命和永久性幼虫形成的调控机制中具有重要的作用。  相似文献   
45.
目的探讨颞叶癫痫的发病机制。方法取健康雄性SD大鼠制成颞叶癫痫模型,用免疫组织化学和原位杂交技术对匹罗卡品致痫后不同时间点CA1区的Sema3C mRNA、Np1 mRNA和蛋白表达进行分析。结果在匹罗卡品致痫后7d,实验组CA1区Sema3C、Np1的表达明显低于对照组(P〈0.01)。结论CA1区Sema3C、Np1的表达下凋可能参与了海马CA1区内的轴突出芽机制。  相似文献   
46.
目的:探讨降纤酶对急性脑梗死(ACI)患者血清超敏C反应蛋白(sCRP)水平的影响及其在改善神经功能缺损方面的作用。方法:46例ACI患者随机分为2组,对照组23例,静脉滴注曲克芦丁注射液,0.6g/d;治疗组23例,入院后立即给予降纤酶10IU溶入250ml生理盐水静脉滴注,1~1.5h滴完,第3、5天各给予降纤酶5IU,其他用药同对照组;应用免疫比浊法检测2组治疗前及治疗后第7天、14天的血清sCRP水平变化,并对神经功能缺损进行评分。结果:2组sCRP水平在治疗后第7天最高,随后逐渐降低。治疗组治疗前血清sCRP水平和治疗前、第7天的神经功能缺损总分与对照组比较差异无统计学意义(P>0.05),治疗组治疗后第7天、14天sCRP水平分别为(7.73±2.16)、(2.92±2.24)mg/L,对照组分别为(10.18±3.16)、(4.66±2.42)mg/L,治疗组明显低于对照组(P<0.05~0.01);第14天治疗组神经功能缺损总分为(10.68±4.08)分,明显低于对照组[(16.81±4.86)分](P<0.01)。结论:降纤酶能明显降低ACI患者血清sCRP水平,有利于减轻炎症反应,改善神经功能缺损程度。  相似文献   
47.
To clarify the prevalence of concurrent infection with hepatitis C virus (HCV), hepatitis B virus (HBV) and human T cell leukaemia virus (HTLV), we measured HCV antibody in the population of a district endemic for HBV and HTLV infection. Blood samples were collected in June 1990 from 579 inhabitants of four islands of Uwa Bay in the southwest of Ehime Prefecture in Japan. Anti-HCV antibody against C100-3 protein was detected using an enzyme-linked immunosorbent assay kit (Ortho Diagnostics). Thirteen of the 579 inhabitants (2.2%) were positive for anti-HCV, and this prevalence rate was not significantly different from the frequency of anti-HCV in Tokyo blood donors. A total of 11% (64 of 579) of the subjects were positive for HBsAg and 3.3% (19 of 579) were positive for anti-HTLV. These frequencies of HBsAg and anti-HTLV positivity were distinctly higher than the respective means of Japanese. All anti-HCV positive individuals were negative for HBsAg and anti-HTLV, while 54% (7 of 13) had increased alanine aminotransferase levels. These data suggest that the prevalence of HCV infection is not high even in an area endemic for HBV and HTLV infection.  相似文献   
48.
A technique has been described for utilizing an existing fixed splint in the fabrication of a fixed partial denture to replace splinted teeth that are extracted.  相似文献   
49.
目的 研究妊娠期糖尿病与胎儿生长发育中糖代谢特点的关系。方法 选择妊娠期糖尿病25例(GDM组),正常孕妇20例(对照组),分别测孕妇空腹血糖、糖耐量、C肽、IGF-I、新生儿出生2h内空腹血糖,并依据新生儿出生体重分为大于胎龄儿组(LGA组,≥4000g),适于胎龄儿组(AGA组,2500-3999g)。结果 C肽及新生儿出生2h内空腹血糖GDM组与对照组差异有显著性;糖耐量各时点血糖值餐后2h血糖值LGA和AGA组差异有显著性。结论 血糖始终是影响胎儿生长发育的重要因素,孕妇餐后2h血糖水平与巨大儿的发生呈正相关。  相似文献   
50.
Recurrence of hepatitis C (HCV) following liver transplantation is common. Herpesvirus reactivation following transplant may have an immunomodulatory effect resulting in increased HCV replication. We studied whether cytomegalovirus (CMV) and human herpesvirus-6 (HHV-6) may be associated with HCV recurrence and viral load after transplant. We prospectively followed 66 HCV liver-transplant recipients with serial viral load testing for CMV and HHV-6. Infection and viral load were correlated with the development of biopsy-proven HCV recurrence and HCV viral loads. Histologic recurrence of HCV occurred in 41/66 (62.1%) patients. In the primary analysis, CMV infection and disease, and HHV-6 infection were not associated with HCV recurrence. Peak CMV and HHV-6 viral loads were not significantly different in patients with and without recurrence. No correlation was observed between HCV viral loads at 1 and 3 months post-transplant and peak HHV-6 or CMV viral loads. In a subgroup analysis, HHV-6 infection was associated with the development of more severe recurrence (hepatitis and/or fibrosis score > or = 2) (p = 0.01). Also, fibrosis scores at last follow up were higher in patients with CMV disease (1.67 vs. 0.56; p = 0.016) and in patients with HHV-6 infection (1.18 vs. 0.55; p = 0.031). In conclusion, HHV-6 and CMV infection and viral load were not associated with increased overall rates of HCV recurrence or HCV viral load after liver transplantation but may be associated with more severe forms of recurrence.  相似文献   
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