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排序方式: 共有6197条查询结果,搜索用时 15 毫秒
1.
RNA干扰及其在胶质瘤基因治疗中的应用   总被引:1,自引:0,他引:1  
RNA干扰(RNA interference。RNAi)是双链RNA(double—stranded RNA,dsRNA)降解特异性靶基因转录出的mRNA。从而抑制靶蛋白表达的现象。自从二十世纪九十年代发现RNAi这一现象以来,RNAi已被广泛应用于研究基因功能、信号转导通路和基因治疗等方面。随着分子生物学、分子遗传学等学科的发展.发现了许多与肿瘤发生、发展和预后密切相关的基因。经过大量临床前期试验表明,针对特异性靶基因的小干扰RNA(short/small interfering RNA.siRNA)治疗胶质瘤是行之有效的。为基因治疗胶质瘤提供了新的思路。[第一段]  相似文献   
2.
载脂蛋白E基因多态性与脑梗死的相关性分析   总被引:12,自引:0,他引:12  
目的 探讨载脂蛋白 E基因多态性与脑梗死的关系。方法 通过聚合酶链反应 -限制性片段长度多态性 (PCR- RFL P)分析结合 DNA直接银染技术检测 6 6例脑梗死 (CI)患者的载脂蛋白 E(Apo E)基因型 (其中家系中有明确脑梗死先证者的家族聚集性脑梗死 (FMACI)亚组 2 6例 ,家系中无脑卒中史的非家族聚集性脑梗死 (NF-MACI)亚组 4 0例 ) ,并与 90例健康对照组比较 ,同时检测血脂、脂蛋白 (a) [L P(a) ]及部分载脂蛋白。结果 脑梗死组ε3/4基因型频率明显高于对照组 (P<0 .0 1) ,ε3/3基因型频率明显低于对照组 (P<0 .0 1) ;两脑梗死亚组之间的ε3/4/ε3/3基因型频率虽有上升 /下降趋势 ,但未发现明显的统计学差异 ;FMACI组高密度脂蛋白 (HDL )水平明显低于 NFMACI组 (P<0 .0 5 )。结论  Apo E基因多态性与脑梗死的发生有关 ,ε4等位基因是脑梗死的易感因子 ,ε3等位基因对脑梗死的发生有保护作用 ;Apo E基因多态性和 HDL水平双重作用于家族聚集性脑梗死的发生。  相似文献   
3.
The prevalence of cardiovascular disease (by EKG criteria) in patients with rhegmatogenous retinal detachments has been reported to be more than four times that found in age-matched controls. Adhesion between the retinal pigment epithelium (RPE) and the photoreceptors is facilitated by RPE transport. Because RPE transport is driven by a Na-K ATPase, it has been suggested that the correlation of EKG abnormalities and retinal detachment may be due to clinical use of digoxin, a Na-K ATPase inhibitor frequently given to patients with cardiovascular disease. The prevalence of EKG abnormalities in 299 consecutive patients with primary retinal detachment is about the same as that reported previously. However, 92% of these patients with EKG abnormalities did not take digoxin. Therefore, clinical use of digoxin cannot account for the reported association of EKG abnormalities and rhegmatogenous retinal detachment.  相似文献   
4.
Adhesion formation is a major source of postoperative morbidity and mortality. In this study, the ability of a variety of lazaroid formulations [the antioxidant 21-aminosteroid PNU74006F (tirilazad) and the non-steroidal 2-methylaminochroman derivative PNU83,836E] to reduce i.p. adhesion formation in three rabbit models was examined. In initial studies, PNU83836E was administered via Alzet miniosmotic pump to the site of injury. In the sidewall and double uterine horn models, PNU83,836E was administered via Alzet miniosmotic pump for the entire postoperative interval. In the sidewall model, there was a dose- dependent reduction in the area of the sidewall injury that was involved in adhesions. In the double uterine horn model, PNU83,836E was administered via Alzet miniosmotic pump to the area of injury for 1, 2, 3 or 7 days. Administration for as little as 24 h after surgery significantly reduced the extent of adhesion formation and the reduction was increased if it was administered for longer. Further studies were conducted in which various lazaroid formulations were administered as a bolus at the end of surgery. In both the sidewall and double uterine horn models, administration of either PNU83,386E (in citrate buffer) or PNU74006F (in cyclodextrin or lipid emulsion vehicles) at the end of surgery reduced adhesion formation. Administration of a bolus of PNU74006F 10 min prior to initiation of surgery with or without additional treatment at the end of surgery further increased its efficacy in the reduction of adhesion formation. Administration of a minimum of 1.5 mg before and after surgery (3 mg total) was required for maximal efficacy. These studies demonstrate that pre- and postoperative administration of either a steroidal (PNU74006F) or non-steroidal (PNU83,836E) lazaroid intraperitoneally reduced the formation and reformation of postoperative adhesions in three animal models.   相似文献   
5.
难治性便秘综合治疗及影响因素的评价   总被引:1,自引:0,他引:1  
目的评价综合治疗对难治性便秘的疗效及影响因素。方法将84例难治性便秘分为非重叠组和重叠组。应用个体化综合治疗4周,观察便秘症状评分变化及总有效率,分析IC患者的重叠症状和心理障碍状态对疗效的影响。结果(1)84例便秘患者中,重叠组和非重叠组分别占40.5%和59.5%。(2)重叠组和非重叠组的总有效率分别为50.0%和78.0%(P<0.05)。(3)对37例IC患者的心理测试调查显示,59.4%(22/37)有心理障碍状态,重叠组和非重叠组伴有心理障碍状态对治疗的总有效率分别为4.8%和31.5%(P<0.05)。结论适合个体化的综合治疗使多数难治性便秘缓解症状,但伴有重叠症状,尤其心理障碍状态则影响疗效。  相似文献   
6.
This study explores marital processes that may underlie the apparent decline in satisfaction with marriage in partners becoming parents for the 1st time. The study assessed 47 couples expecting a 1st child and 15 couples not yet decided about having a child at pretest, post 1 (6 months post partum of 9 months after pretest) and post 2 (18 months postpartum or 21 months after pretest). Questionnaires examined: 1) psychological sense of self; 2) partners' role arrangements and communication; 3) parenting ideology; 4) perceptions of the family of origin; and 5) social support and life stress, including parents' work patterns. Parenthood seems to bring more change, and more negative change, in each of the 5 domains of family life that were investigated for comparable couples not having a 1st child experience over a similar period of time. Quantitative data support this conclusion in 4 of the 5 domains (individuals sense of self, marital, parent-child, and outside the family). Interview data suggest that new parents' relationships with their families of origin also undergo change at this time. Although shifts within domains often showed patterns similar to change in overall satisfaction with the marriage, the connection between the 2 was not linear and direct, especially for women. Men and women in transition to parenthood become increasingly different from one another; the results suggest that increased gender differentiation accompanying the transition to parenthood is a factor in accounting for marital satisfaction decline.  相似文献   
7.
Global versus local processing: Is there a hemispheric dichotomy?   总被引:1,自引:0,他引:1  
D B Boles 《Neuropsychologia》1984,22(4):445-455
A major dichotomy proposed for lateralized information processing is that the right and left cerebral hemispheres are "global" and "analytic" processors respectively. Here three experiments employed a tachistoscopic recognition paradigm with letter patterns varying in size and composition. No visual field asymmetries in RT were found in the first two experiments, although statistical power was high and a Stroop-like effect ("global precedence") was supported. Experiment 3 resulted in a right field advantage for vocal naming responses yet no asymmetry for manual responses, suggesting that both hemispheres can recognize global and local patterns, but that introduction of a laterally controlled response independently determines asymmetry.  相似文献   
8.
Objective To evaluate the long-term therapeutic effects of autologous peripheral blood st em cell transplantation (auto-PBSCT) on the treatment of hematological and soli d tumors. Methods Fifty-one patients were recruited in this auto-PBSCT study, in which several p otentially important parameters were studied including the optimal time for stem cell co llection, the dose of stem cell reinfusion, the time of hematopoietic reconsti tution, the disease free survival (DFS) and overall survival (OS), complication s related to transplantation, and maintenance chemotherapy after auto-PBSCT. Results After APBSCT, 3-year and 5-year survival rates of NHL were 83.3%; those of AM L were 74.7%; those of MM were 37.9% and 19%; those of ALL were 40% and 0% res pectively. Hematopoietic reconstitution was greatly promoted by granulocyte col ony stimulating factor (G-CSF). The mean time for patients’ neutrophil to reco ver up to &gt;0.5×10(9) /L after APBSCT was 11.14 days in the group of the patien ts receiving G-CSF in contrast to 17.6 days in the group receiving no G-CSF. The most common complications of transplantation were fever, liver dysfunction and hypokalaemia, which were curable. No death was due to transplantation related complications.Conclusion Comparing with conventional chemotherapy, our study suggests that auto-PBSCT i s a very important therapeutic option that can significantly improve the prognos is in the patients with hematological and solid tumors, especially in the patien ts with AML and NHL.  相似文献   
9.
目的 :探讨国人无综合征性耳聋 ( NSD)患者的线粒体 DNA 744 5 A→ G( m t DNA744 5 A→ G)突变的发生情况。方法 :对 32个 NSD家系 12 8例和 135例散发的 NSD患者 ,10 0例正常人 ,以 PCR法检测 mt DNA 744 5 A→ G突变情况。结果 :全部受检者无 mt DNA744 5 A→ G突变发生。结论 :国人 NSD患者的 m t DNA744 5 A→ G突变的发生率较低 ,且明显低于 mt DNA15 5 5 A→ G的突变发生率  相似文献   
10.
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