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111.
112.
Effective intracellular delivery of oligonucleotides in order to make sense of antisense. 总被引:5,自引:0,他引:5
For more than two decades, antisense oligonucleotides (ODNs) have been used to modulate gene expression for the purpose of applications in cell biology and for development of novel sophisticated medical therapeutics. Conceptually, the antisense approach represents an elegant strategy, involving the targeting to and association of an ODN sequence with a specific mRNA via base-pairing, resulting in an impairment of functional and/or harmful protein expression in normal and diseased cells/tissue, respectively. Apart from ODN stability, its efficiency very much depends on intracellular delivery and release/access to the target side, issues that are still relatively poorly understood. Since free ODNs enter cells relatively poorly, appropriate carriers, often composed of polymers and cationic lipids, have been developed. Such carriers allow efficient delivery of ODNs into cells in vitro, and the mechanisms of delivery, both in terms of biophysical requirements for the carrier and cell biological features of uptake, are gradually becoming apparent. To become effective, ODNs require delivery into the nucleus, which necessitates release of internalized ODNs from endosomal compartments, an event that seems to depend on the nature of the delivery vehicle and distinct structural shape changes. Interestingly, evidence is accumulating which suggests that by modulating the surface properties of the carrier, the kinetics of such changes can be controlled, thus providing possibilities for programmable release of the carrier contents. Here, consideration will also be given to antisense design and chemistry, and the challenge of extra- and intracellular barriers to be overcome in the delivery process. 相似文献
113.
目的分析影响肝癌肝移植术后生存率和无瘤生存率的危险因素,探讨国内肝移植治疗肝癌的选择标准。方法对67例接受同种异位原位肝移植治疗的原发性肝癌病人的基本资料和肿瘤相关资料包括术前病情分级、血清AFP水平、术前辅助治疗以及肝癌大小、数目、pTNM分期、肿瘤恶性程度分级等因素进行单因素和多因素分析。结果术后1年、2年累积生存率为77%、67%,6个月和12个月无瘤生存率为66%和58%。单因素分析显示对肝癌肝移植术后累积生存率影响有统计学意义的因素为CHILD分级(MELD积分)和肝外大血管侵犯;多因素分析影响肝癌肝移植术后无瘤生存率有统计学义的因素是肿瘤大小、大血管侵犯和肿瘤分化程度。结论影响肝癌肝移植术后生存率的因素仍是术前患者肝功能状态。对存在大血管侵犯的肝癌患者需严格控制肝移植术适应证,而无血管侵犯的患者在选择肝移植治疗时肿瘤大小指标可较米兰标准适当放宽。 相似文献
114.
Zhipan Zhang Gaoquan Shi 《Journal of electroanalytical chemistry (Lausanne, Switzerland)》2004,569(2):197-202
Poly (3-phenylthiophene) (P3PhT) films have been electrochemically synthesized by direct oxidation of 3-phenylthiophene in the electrolyte of pure boron trifluoride diethyl etherate (BFEE). The oxidation potential of the monomer was measured to be 1.29 V (vs. SCE), and about 0.15 V lower than that measured in a neutral medium of acetonitrile. Free-standing P3PhT film with tensile strength of 32–40 MPa has been obtained for the first time. The morphology and the structure of the polymer film have been studied by scanning electron microscopy, infrared and Raman spectroscopies. Raman spectral results demonstrated that the doping level of the P3PhT film increased with film thickness during electrochemical growth process. 相似文献
115.
目的通过动物实验观察不同骨水泥强化松质骨螺钉的生物力学和组织学变化动态,为骨质疏松骨折患者内固定提供理论基础。方法在10只杂种犬胫骨近端制作松质骨螺钉植入的动物模型,分别采用碳酸化羟基磷灰石水泥(CHC)和聚甲基丙烯酸甲酯(PMMA)强化,分别于术后5d、4、8、12和16周处死动物,观察螺钉拔出的生物力学和组织学变化。结果CHC强化的螺钉拔出力随手术后时间的延长而逐渐升高,16周时达到(512.5 14.5)N,而PMMA强化组螺钉拔出力则随手术后时间的延长而逐渐降低。CHC-骨界面结合紧密,并且随时间延长出现CHC降解和骨长入,而PMMA-骨界面形成一层纤维组织。结论CHC强化能够提高松质骨螺钉植入体内的稳定性,并且随植入时间延长而逐渐升高。 相似文献
116.
对13例慢性重症肝炎合并低钾血症患者采用微量泵大剂量高浓度补钾,结果3~14d血钾均达到正常水平,无严重不良反应出现。提示利用微量泵补钾安全有效,但应注意高浓度钾对血管的刺激以及注意观察患者症状和心电图变化。 相似文献
117.
相对于普通高校,高职高专学校中学业不良学生的比例更高,管理的难度更大。因此,分析、研究学生学业不良的成因,并采取科学有效的措施予以矫正,对于促进学生健康成长,全面提高教育教学质量,具有积极的意义。 相似文献
118.
Microsomal glutathione transferase 1 is not S-nitrosylated in rat liver microsomes or in endotoxin challenged rats. 总被引:1,自引:0,他引:1
In vitro activation of purified rat microsomal glutathione transferase 1 (MGST1) by S-nitrosylation has been recently reported. This study was designated to explore its in vivo relevance. Unexpectedly, we failed to detect S-nitrosylated MGST1 in rat liver microsomes treated with S-nitrosoglutathione (GSNO); neither did we observe MGST1 S-nitrosylation in endotoxin challenged rats. However, by using matrix-assisted laser dissociation/ionization time-of-flight mass spectrometry (MALDI-TOF MS), we identified several other proteins which are susceptible to S-nitrosylation in liver microsomes, including retinol dehydrogenase type I (RODH I), aldolase B, cytochrome P4502C11, and peroxiredoxin 1. Our results suggest that MGST1 S-nitrosylation is unlikely to be involved in the protection mechanism against nitrosative stress caused by endotoxin challenge. Further studies on the novel S-nitrosylable microsomal proteins are also warranted. 相似文献
119.
Stem cells and periodontal regeneration 总被引:10,自引:0,他引:10
120.
慢性心力衰竭的CT表现 总被引:3,自引:1,他引:2
目的:探讨慢性心力衰竭的CT表现。材料和方法:回顾性分析28例慢性心力衰竭的CT表现。结果:左心室增大16例、右心室增大8例、左心房增大6例、右心房增大4例,左、右心房增大3例,肺水肿24例、胸腔积液25例、肺动脉扩张3例、升主动脉扩张5例和冠状动脉钙化7例。左心衰CT示肺水肿、左心室扩大和胸腔积液。右心衰CT示右心室扩大、主肺动脉扩张和胸腔积液。全心衰竭CT示左右心室扩大,肺水肿和双侧胸腔积液。结论:CT可显示心脏各房室扩大、大动脉扩张、肺水肿、胸腔和心包积液以及冠状动脉钙化,为诊断原发心脏疾病及慢性心力衰竭提供重要依据。 相似文献