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91.
目的探讨运动神经元病(MND)患者胸锁乳突肌(SCM)肌电图的特征。方法回顾性分析461例MND患者及349例非MND患者的临床和肌电图资料。结果MND组SCM肌电图异常率(60.3%)显著高于非MND组(4.6%)(P<0.01);确诊级MND患者SCM肌电图的异常率(77.4%)明显高于其他诊断级(均P<0.01);MND组中,SCM肌电图的异常率(60.3%)低于上、下肢体肌肉的肌电图(93.2%、84.4%)(均P<0.001);MND患者SCM肌电图异常以自发电位(42.5%)和轻收缩时运动单位电位时限增宽(43.2%)最为常见;MND组有延髓症状者SCM肌电图的异常率(71.7%)明显高于无延髓症状者(54.3%)(P<0.05)。结论MND患者SCM肌电图异常率及其特异性高,为延髓肌受累的指征,有助于MND的诊断与鉴别诊断。 相似文献
92.
B. Hohenester A. Rühl O. Kelber† & M. Schemann 《Neurogastroenterology and motility》2004,16(6):765-773
Functional dyspepsia (FD) is amongst the most common functional gastrointestinal disorders. Symptomatic treatment includes the use of herbal preparations whose effects on gastric motility are unclear. The present study aimed at investigating the effects of STW 5 (Iberogast), a fixed combination of hydroethanolic herbal extracts, on gastric motility in vitro. Muscle strips from guinea-pig gastric fundus, corpus and antrum were set up in organ baths either in circular or longitudinal orientation. Addition of ethanol-free STW 5 to the organ baths (32-512 microg mL(-1)) dose-dependently evoked a sustained and reversible relaxation of circular and longitudinal fundus and corpus muscle strips without changes in phasic activity. In contrast, antral muscle strips responded to STW 5 with a significant increase in the contractile force of phasic contractions without changes in tone. All effects were resistant to tetrodotoxin (0.5 micromol L(-1)), atropine (1 micromol L(-1)), omega-conotoxin GVIA (0.5 micromol L(-1)), capsaicin (1 micromol L(-1)) or L-NAME (100 micromol L(-1)), suggesting that neither nerves nor nitric oxide pathways were involved. These data demonstrate that STW 5 profoundly alters gastric motility in a region-specific but not layer-specific manner and thus implicates Iberogast in the treatment of FD patients suffering from motility disorders with impaired fundus accommodation and/or antral hypomotility. 相似文献
93.
目的:探讨黄芪注射液对SHR心肌SERCA的表达及血管平滑肌钙离子含量的影响.方法:将19只自发性高血压大鼠(SHR)与16只Wistar-kyoto大鼠(WKY)随机各分为空白对照组、低黄芪剂量组、中黄芪剂量组、高黄芪剂量组四组,分别每天腹腔注射0.9ml生理盐水和0.9ml、1.2ml、1.8ml的黄芪注射液共8周,再测量大鼠心肌中SERCA的表达和血管平滑肌钙离子含量.结果:SHR生理盐水组心肌SERCA在蛋白水平的表达,较WKY生理盐水组明是下降;SHR大剂量黄芪组心肌SERCA在蛋白水平的表达,较SHR生理盐水组明显升高.SHR生理盐水组血管平滑肌钙离子水平明显高于WKY组:SHR大剂量黄芪组血管平滑肌钙离子水平较SHR生理盐水组明显降低.结论:大剂量黄芪注射液能显著增加SHR心肌SERCA在蛋白水平的表达,能明显的减少SHR血管平滑肌钙离子的水平. 相似文献
94.
95.
Decreased expression of DMPK: correlation with CTG repeat expansion and fibre type composition in myotonic dystrophy type 1 总被引:2,自引:0,他引:2
S. Salvatori M. Fanin C. P. Trevisan S. Furlan S. Reddy J. I. Nagy C. Angelini 《Neurological sciences》2005,26(4):235-242
Abstract Myotonic dystrophy type 1 (DM1) is an autosomal dominant disease caused by a trinucleotide repeatexpansion, cytosine-thymine-guanine
(CTG)n, in the 3′ untranslated region of a gene encoding the myotonic dystrophy protein kinase (DMPK). To correlate CTG expansion
and protein expression, we studied muscle specimens from 16 adult DM1 patients using three anti-DMPK antibodies for immunoblotting.
We estimated the amount of the full-length DMPK (85 kDa) in muscle biopsies from normal controls and from DM1 patients carrying
different (CTG)n expansions. We found that DMPK concentration was decreased to about 50% in DM patients’ muscles; the protein decrease did
not seem correlated with the CTG repeat length. However, the fibre type composition in skeletal muscle seemed somehow to affect
DMPK decrease, as the lowest level of the enzyme was found in patients with the lowest content of type 1 fibre. 相似文献
96.
Andrew K. C. Lam Abby Lam Jessie Charm Kwai-mui Wong 《Ophthalmic & physiological optics》2005,25(2):162-167
PURPOSE: This study compared the near phoria measurement using the Bernell muscle balance card with and without prism neutralization, using both trial frame and phoropter correction, and compared with the conventional Maddox rod method. METHODS: Forty young normal Chinese adults had their near phoria measured with trial frame correction using the conventional muscle balance card method (method 1). Any deviation was compensated with a prism bar as an alternative approach (method 2). The conventional Maddox rod method (method 3) was also carried out for comparison. These three methods were repeated with phoropter correction and considered as methods 4, 5 and 6. RESULTS: The phorias obtained from these six methods were not significantly different from each other (repeated measures anova, p > 0.05). More than half of the subjects were exophoric. Although the difference in phoria was not significant, phoria measurement using phoropter correction yielded a greater coefficient of variation. CONCLUSIONS: Near phoria measurement using the muscle balance card conducted with trial frame correction was less variable, and was also more natural and similar to a real reading situation. The use of prism for compensation did not affect the phoria results. Exophoria seems to be more common than esophoria in young Chinese adults. 相似文献
97.
Effects of ageing on the total number of muscle fibers and motoneurons of the tibialis anterior and soleus muscles in the rat 总被引:1,自引:0,他引:1
The age-related changes in the total number of muscle fibers and motoneurons of the tibialis anterior and soleus muscles were studied using 10-, 65-, and 135-week-old rats. The number of fast twitch muscle fibers was decreased at age 65 weeks, while the numbers of slow twitch fibers and of alpha motoneurons were decreased only later, at age 135 weeks. Therefore, the degenerative process of muscle fibers differs with the fiber type. 相似文献
98.
目的构建以HGF为目的基因、以EGFP为报告基因的非融合蛋白真核表达载体pCMV-HGF-IRES-EGFP,并观察HGF基因在原代培养的大鼠骨骼肌细胞中的表达。方法利用BamHI单酶切质粒pcDNA3-HGF,得到HGF基因片段,将其正向插入到真核表达载体pCMV-IRES-EGFP的CMV后方BamHI的单克隆位点。脂质体介导转染至原代培养的大鼠骨骼肌细胞,在荧光显微镜下观察EGFP的表达,并用ELISA法检测HGF的表达情况。结果构建了HGF的非融合蛋白真核表达载体pCMV-HGF-IRES-EGFP,转染原代培养的大鼠骨骼肌细胞24~72h后,见30%的细胞表达EGFP。ELISA检测细胞培养液证实转染后第1天即有HGF的表达,第4天HGF浓度为(5402.0±227.9)ng/L。结论成功构建了非融合蛋白真核表达载体pCMV-HGF-IRES-EGFP,其在原代培养的大鼠骨骼肌细胞中能有效表达。 相似文献
99.
Pinacidil抑制线粒体和死亡受体通路减少大鼠脑缺血再灌注后神经元凋亡(英文) 总被引:4,自引:1,他引:3
目的探讨ATP敏感性钾通道开放剂pinacidil对大鼠脑缺血再灌注后神经元凋亡的保护作用及信号转导机制。方法 100 只Wistar 雄性大鼠随机分为四组:A 组(假手术组)、B组 (缺血组)、C 组 (KATP开放剂处理组)及D组 (KATP开放剂和阻断剂处理组)。用线栓法制备大鼠大脑中动脉缺血(middle cerebral artery occlusion,MCAO)模型,用DNA断端末端标记法(terminal-deoxynucleotidytransferase-mediated dUTP-biotin nick end labeling,TUNEL)检测神经元凋亡,用原位杂交方法检测caspase-3、caspase-8及caspase-9 mRNA的表达。结果 (1) C组12 h、24 h、48 h、72 h 时间点的凋亡细胞数较 B、D 组显著减少(P<0.05 或 P<0.01) ;B 组和 D组之间无显著性差异(P>0.05)。(2) C 组 caspase-3 mRNA 和 caspase-8 mRNA 在各时间点及 caspase-9 mRNA 在 12 h、24 h、48 h、72h 时间点的表达显著少于B组和D组(P<0.01或P<0.05),B组和D组之间无显著性差异(P>0.05)。结论 KATP通道开放剂能显著减少大鼠脑缺血再灌注后的细胞凋亡及caspase-3、caspase-8及caspase-9 mRNA的表达。KATP通道开放剂可能通过抑制线粒体通路和死亡受体通路降低神经元凋亡,保护缺血再灌注损伤后的脑组织。 相似文献
100.
低氧及运动致大鼠骨骼肌形态学改变的实验研究 总被引:6,自引:0,他引:6
目的观察低氧及低氧复合运动时,大鼠体重及腓肠肌显微、超微结构的变化,旨在探讨低氧状态下适当运动对骨骼肌的影响。方法建立大鼠低氧及低氧复合运动模型,运用光镜及透射电镜观察大鼠腓肠肌显微、超微结构的变化。结果低氧复合运动组较低氧安静组大鼠体重差异有显著性意义(P<0.05)。低氧复合运动组骨骼肌结构正常,线粒体数量增加,骨骼肌纤维增粗,毛细血管增生。结论低氧复合适当的运动能够维持骨骼肌的正常形态,增强骨骼肌的有氧代谢,起到保护骨骼肌的作用,从而提高骨骼肌的低氧适应能力,促进低氧习服。 相似文献