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101.
肾母细胞瘤RASSF1A基因启动子区甲基化研究   总被引:3,自引:0,他引:3  
目的了解肾母细胞瘤RASSF1A基因启动子区甲基化情况。方法手术获取9例肾母细胞瘤及瘤旁残留肾组织,提取DNA后用亚硫酸氢钠处理,巢式PCR扩增RASSF1A基因启动子区DNA片段,测序,检测启动子区甲基化情况。结果发现1例16个CpG岛位点中有10个存在甲基化(10/16),相应瘤旁残留肾组织无甲基化(0/16);在另1例瘤组织中检测到12个CpG岛位点存在甲基化(12/16),但仅有8个CpG岛位点与上例相同,另外4个位点不同。结论肾母细胞瘤中RASSF1A基因启动子区存在甲基化,与瘤旁残留肾组织甲基化情况有差别。  相似文献   
102.
目的探讨脊髓血管畸形是否存在血管内皮生长因子(VEGF)表达,及其表达与临床特征之间是否存在相关性。方法在手术中留取56例脊髓血管畸形的脑脊液标本,其中动静脉畸形(SCAVM)23例,硬脊膜动静脉瘘(SDAVF)19例,海绵状血管瘤(CM)14例;以我院12例蛛网膜下腔阻滞病人脑脊液作为对照组,分别通过酶联免疫吸附方法(ELISA)测定脊髓血管畸形脑脊液中VEGF含量。结果SCAVM脑脊液中VEGF浓度为(277±66)pg/ml、SDAVF为(318±54)pg/ml、CM为(146±32)pg/ml均高于正常对照组(123±27)pg/ml。术前栓塞和出血均可导致脑脊液VEGF升高。结论VEGF与脊髓血管畸形的发生、发展存在一定关系,出血和栓塞均可影响VEGF的表达。  相似文献   
103.
Synkinesias secondary to nerve lesions and aberrant re-innervation are well-known phenomena especially after lesions of the facial nerve. Synkinesias can successfully be treated with botulinum toxin A (BTx A). Synkinesias of the cremaster muscle have not been described or treated to date. We present the case of a 62-year-old man who developed synkinesias of both cremaster muscles after extensive laparatomy for esophageal cancer. Treatment of synkinesias with various oral medications had been unsuccessful. Electromyography-guided injections of BTx A in both cremaster muscles (15 MU on the right and 10 on the left) led to significant symptom relief for an average of 8 weeks. We present the case including pre- and posttreatment video clips.  相似文献   
104.
It is well known that migraine has a strong genetic component, although the type and number of genes involved remains unclear. There is evidence to suggest that serotonin-related genes may be involved in the pathogenesis of migraine. To investigate whether the 5-HT1A receptor gene contributes to the risk of migraine we performed an association study of C-1019G promoter polymorphism of the gene in 102 migraineurs and 93 controls. Subjects were of Han Chinese origin. No significant differences in allele (P=0.82) or genotype frequencies (P=0.71) were seen in migraineurs compared with the controls. When migraine with aura, without aura, with family history, without family history were analyzed separately, the frequencies did not vary significantly. Our results suggest that C-1019G in 5-HT1A is not a major genetic risk factor for migraine.  相似文献   
105.
目的探讨转移相关蛋白(nm23和P53及S100A4)在晚期胃癌转移发展过程中的意义。方法应用组织芯片和免疫组织化学方法研究nm23、P53和S100A4在74例胃癌患者的癌、癌旁、淋巴结转移、远处转移(肝脏、胰腺、卵巢等)组织中的表达。结果同癌旁组织相比,癌组织中P53和S100A4表达明显升高(P〈0.01),而nm23的表达明显降低(P〈0.05);同癌组织相比,淋巴结中nm23的表达明显降低(P〈0.05)。远处转移组织S100A4表达明显升高(P〈0.01)。3者的阳性表达与胃癌的部分恶性生物学行为有关。癌组织中nm23^+/P53^+、P53^+/S100A4^+和nm23^+/S100A4^+的基因表型比例分别为48例(64.9%)、50例(67.6%)和39例(52.7%),其中P53^+/S100A4^+、nm23^+/S100A4^+和nm23^+/P53^+/S100A4^+均与胃癌的高转移潜能相关。结论nm23和S100A4在肿瘤转移中发挥了重要作用;联合检测nm23、P53和S100A4的表达可用于评定胃癌的转移潜能。  相似文献   
106.
目的 大量富集三裂叶蟛蜞菊倍半萜内酯A,B(WTA,WTB)。方法 采用气相色谱法测定WTA和WTB,并以WTA和WTB的含量、洗脱率、精制度为考察指标,研究D101大孔树脂吸附WTA和WTB的工艺条件及参数。结果 通过大孔树脂吸附后,WTA和WTB的洗脱率达90%,50%乙醇洗脱部分中WTA和WTB的含量为总固物的4.01%~4.09%。结论 可以采用大孔树脂富集WTA和WTB。  相似文献   
107.
Clinical efficacy, safety and pharmacokinetic properties of the high-purity double-virus inactivated plasma-derived factor VIII concentrate Haemoctin SDH (pdFVIII) were evaluated in three prospective open-label uncontrolled studies in previously treated patients (PTPs) with severe haemophilia A. The pharmacokinetic properties assessed at baseline and after 3 months of treatment are in accurate accordance with published data and remain unchanged over time (study A, n = 12). Mean terminal elimination half-life was 11.8 and 11.9 h, mean incremental recovery (IU dL(-1)/IU kg(-1)) was 2.3 and 2.0, respectively. Long-term efficacy and safety, in particular the potential immunogenicity, were investigated in a total of 53 PTPs (studies A and B) treated prophylactically and on-demand, as required. PdFVIII has shown to be effective in preventing and controlling bleeding episodes; 23.5% of patients were free of bleeding events. A total of 177 haemorrhages occurred with 74.0% resolving after a single infusion, 87.6% within two infusions. 98.3% of responses reported on haemorrhages were rated as 'excellent' or 'good'. Moreover, 'excellent' haemostatic efficacy has been demonstrated in 10 surgical procedures including general and severe orthopaedic interventions (study C). No complication occurred in any surgery. Few adverse events were reported, one patient developed a high-titre FVIII inhibitor without clinical relevance. In all three studies, over 6 million units were administered in nearly 4300 infusions, approximately 94% units or infusions were given for prophylaxis and only 6% for treatment on-demand. In conclusion, pdFVIII has shown to be effective, safe and well tolerated in long-term prophylaxis and treatment on-demand as well as after minor and major surgical procedures.  相似文献   
108.
Early multiple organ dysfunction syndrome appears to be facilitated with bacterial translocation in severely burn injury, yet the mechanisms of bacterial translocation remains in dispute. The aim of this study was to investigate the potential role of intestinal bifidobacteria in the pathogenesis of gut-derived bacteria/endotoxin translocation following burns and the effects of bifidobacterial supplement on gut barrier. Methods: Wistar rats were randomly divided into burn group (Burn, n=60),sham burn group (SB, n=10) in experiment Ⅰ , and burn + saline group (BS, n=30), burn + bifidobacteria group (BB, n=30), and sham-burn + saline group (SS, n= 10) in experiment Ⅱ. Animals in BB group were fed bifidobacterial preparation (5 × 109 CFU/ml) after burns, 1.5ml,twice daily. Animals in BS and SS were fed saline. Samples were taken on days 1, 3, and 5 in burn groups, and on day 3 in sham-burn groups. The incidence of bacteria/endotoxin translocation and counts of Bifidobacterium, Fungi and Escherichia coli in gut mucosa were determined with standard methods. The levels of sIgA in mucus of small intestine were measured by RIA. The positive sIgA expression in lamina propria and ileum mucosal injury was evaluated light microscopically by blinded examiners. Results: Our results showed that the incidence of bacterial translocation was increased after burns, which was accompanied by significant decrease in number of bifidobacteria but significant increase in E. coli and fungi in gut mucosa, and elevation of levels of plasma endotoxin and IL-6 (P<0. 001).The incidence of bacterial translocation was markedly reduced after 3- and 5-day supplementation of bifidobacteria compared with control group (P<0.05). The counts of mucosal bifidobacteria were increased by 4- to 40-fold,while E. coli and fungi were decreased by 2- to 30-fold and 10- to 150-fold, respectively, after bifidobacterial supplementation in contrast to control group. The damage of mucosa tended to be less pronounced after 3-day bifidobacteria-supplemented formula compared with control group [grade 2(0-6) vs. grade 4(3-6), P<0.05]. Moreover, the expression and release of sIgA was markedly augmented after 3-day bifidobacteria-supplementation formula and it returned to normal range on day 5. Conclusion: The decrease in counts and proportion of bifidobacteria in mucous membrane flora may play an important role in the development of bacteria/endotoxin translocation following thermal injury. The supplement of exogenous bifidobacteria could per se improve gut barriers, and attenuate bacteria/endotoxin translocation secondary to major burns.  相似文献   
109.
竹叶柴胡化学成分的研究   总被引:3,自引:0,他引:3  
目的:为了开发利用竹叶柴胡(Bupleurum marginatum Wall.ex DC.)天然资源,阐明其有效成分,对竹叶柴胡根进行了化学成分研究。方法:运用层析手段和波谱方法分离并鉴定化合物。结果:分离并鉴定13个化合物,它们的结构分别被鉴定为( )-anomalin(Ⅰ),白花前胡丙素(( )-praeruptorin A)(Ⅱ),(4),( )3’-angeloyloxy-4’-keto-3’,4’-dihydroseselin(Ⅲ),木糖醇(xyhtol)(Ⅳ),柴胡色原酮A(saikoehromone A)(Ⅴ),6”-O-乙酰基柴胡皂苷d(6”-O-acetylsaikosaponin d)(Ⅵ),柴胡皂苷b4(saikosaponin b4)(Ⅶ),柴胡皂苷a(saikosaponina)(Ⅷ),柴胡皂苷d(saikosaponin d)(Ⅸ),柴胡皂苷b2(saikosaponin b2)(Ⅹ),柴胡皂苷c(saikosaponin c)(Ⅺ),此外还有β-谷甾醇,β-胡萝卜甙。结论:化合物Ⅰ,Ⅱ,Ⅲ,Ⅳ,Ⅴ,Ⅵ,Ⅷ,Ⅹ均为首次从竹叶柴胡中分得,其中化合物Ⅱ和Ⅲ为首次从该属植物中分得。  相似文献   
110.
目的我们前期的实验结果显示A20 mRNA和蛋白在人脑胶质瘤组织及细胞系(U251、U87、BT325)中高表达,本研究拟构建A20RNAi载体,并检测其对U251细胞A20表达的抑制作用。方法构建三种针对人A20基因的真核干涉表达载体,以脂质体法将其分别转染人脑胶质瘤细胞系U251,以RT-PCR、蛋白印迹法检测各干涉载体对U251细胞中A20mRNA和蛋白表达的抑制作用。结果成功构建三种针对A20基因的RNAi载体,经RT-PCR、蛋白印迹检测筛选出对A20基因干涉效果最佳的载体,命名为pSilencer3.1-A20R1。结论成功构建A20基因干涉载体,为进一步探讨A20与脑胶质瘤恶性增殖、血管形成以及抗凋亡的关系奠定实验基础。  相似文献   
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