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221.
卟啉类化合物因其独特的物理和化学特性,在肿瘤治疗领域具有广阔的应用前景.但是卟啉类化合物存在水溶解性较差和易于自聚集等缺点,限制了其在肿瘤治疗上的广泛应用.而金属有机框架(MOFs)具有可调节孔径、可功能化修饰,以及生物相容性好等优点.因此,将卟啉作为有机连接体,结合金属簇构建卟啉MOFs材料,不仅可以克服卟啉类化合物固有的缺点,而且还能发挥MOFs的优异特性.文章综述了近年来卟啉MOFs材料的合成方法及其在肿瘤治疗方面的研究进展,同时探讨了其在肿瘤治疗领域的挑战.  相似文献   
222.
基因工程将是21世纪最具有发展潜力的高新技术。介绍了基因工程及其在基因检测与基因治疗、生物反应器工程、蛋白质工程与代谢工程、基因组计划与生物信息学等相关领域的进展。  相似文献   
223.
本文讨论了目前大肝癌的五种治疗手段:外科手术切除或肝移植、局部区域治疗和化疗、肝癌分子靶向药物治疗。结合循证临床指南,综述在不同分期阶段合理治疗手段的选择,以及各种治疗手段的适应症、禁忌症和预后。  相似文献   
224.
Thrombin is a plasma serine protease that plays a key role in coagulation and hemostasis but also in thromboembolic diseases. Direct thrombin inhibitors could, therefore, be beneficial for future anticoagulant therapy in the prophylaxis of venous and arterial thrombosis as well as myocardial infarction. However, development of direct thrombin inhibitors has brought researchers more heartache than success. The most recent setback came this year when AstraZeneca withdrew Ximelagatran, the first orally bioavailable direct thrombin inhibitor that had received regulatory approval (France, 2003), after reports of serious hepatoxicity in a fraction of patients. This review describes the status of direct thrombin inhibitors, focusing on drug candidates that are at present in clinical trials. In addition, some more recent research strategies in the design of novel direct thrombin inhibitors are discussed, which may very well contribute to future developments of potent anticoagulants. Received 9 May 2006; received after revision 15 June 2006; accepted 23 August 2006  相似文献   
225.
The highly conserved Notch signaling pathway plays pleiotropic roles during embryonic development and is important for the regulation of selfrenewing tissues. The physiological functions of this signaling cascade range from stem cell maintenance and influencing cell fate decisions of barely differentiated progenitor cells, to the induction of terminal differentiation processes, all of which have been found to be recapitulated in different forms of cancers. Although Notch signaling has mostly been associated with oncogenic and growth-promoting roles, depending on the tissue type it can also function as a tumor suppressor. Here we describe recent findings on Notch signaling in cancer and tumor angiogenesis, and highlight some of the therapeutic approaches that are currently being developed to interfere with tumor growth and progression. Received 2 April 2007; received after revision 29 June 2007; accepted 2 July 2007  相似文献   
226.
阿尔茨海默病(Alzheimer's disease,AD)是老年人最常见的神经系统退行性疾病.经β-和γ-分泌酶切割形成的β淀粉样蛋白(amyloid-beta,Aβ)与AD的发生密切相关.γ-分泌酶是一个含有早老素的复合蛋白体,作为Aβ代谢的关键酶,它是治疗AD的潜力的靶点.在过去20年里,药物研究且发现了能抑制或调节γ-分泌酶的小分子化合物,部分化合物已经进入临床研究.本文就Aβ的形成、γ-分泌酶的结构及目前γ-分泌酶的抑制剂、调节剂的研究进展作一综述介绍.  相似文献   
227.
放射治疗在宫颈癌的治疗中应用广泛,是各期患者综合治疗的重要组成部分。放疗与手术、化疗等治疗手段结合的综合治疗模式多样,其中同步放化疗已经成为局部晚期宫颈癌患者的治疗标准,其不同的使用方案以及在术前、术后的应用仍在进一步临床研究中。本文就宫颈癌综合治疗模式中放疗与化疗、放疗与手术结合方式的研究进展做一综述。  相似文献   
228.
We have proposed a chemical chaperone therapy for lysosomal diseases, based on a paradoxical phenomenon that an exogenous competitive inhibitor of low molecular weight stabilizes the target mutant molecule and restores its catalytic activity as a molecular chaperone intracellularly. After Fabry disease experiments, we investigated a new synthetic chaperone compound N-octyl-4-epi-β-valienamine (NOEV) in a GM1-gangliosidosis model mice. Orally administered NOEV entered the brain through the blood-brain barrier, enhanced β-galactosidase activity, reduced the substrate storage, and clinically improved neurological deterioration. We hope that chemical chaperone therapy will prove useful for some patients with GM1-gangliosidosis and potentially other lysosomal storage diseases with central nervous system involvement. Received 10 October 2007; received after revision 31 October 2007; accepted 6 November 2007  相似文献   
229.
New approaches to understanding and designing treatments for Duchenne muscular dystrophy (DMD) may emerge from two hypotheses outlined here. The proposal that growing skeletal muscle is more susceptible to necrosis than adult muscle raises the possibility that less intensive treatments may be sufficient to protect muscles during the adult phase. The second proposal is that a different balance of cell and molecular events contributes to acute necrosis (e.g. resulting from exercise) compared with chronic damage of dystrophic muscle. Validation of such differences presents the potential for more specific targeting of drugs or nutritional interventions to events downstream of the dystrophin deficiency. A deeper understanding of the events arising as an early consequence of dystrophin deficiency in these two situations may strengthen approaches to therapy for DMD designed to improve muscle function and the quality of life. Received 18 December 2007; received after revision 9 January 2008; accepted 25 February 2008  相似文献   
230.
针对目前数据管理中普遍存在的中心化存储、防篡改性弱、可追溯性差、缺乏安全有效的共享渠道等问题,借助区块链技术的去中心化、不可篡改等特性研究了一种基于区块链的精准扶贫数据保护方案.以个人档案的形式记录扶贫数据,依托智能合约和星际文件系统等技术使数据以数字档案形式进行新增、更新、验证、共享.将公有链和联盟链结合,以锚定数据...  相似文献   
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