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1.
Applications of information and communications technology (ICT) for the management of environmental data, if used during the design and at the end of the product life cycle, can improve the environmental performance of products. This specific application of ICT for data management is called product data technology (PDT) and is based on the use of international standards developed by ISO TC184/SC4. PDT enables the computerized representations of information about products, processes, and their properties that are independent of any proprietary computer system or software application. The standard product data models are designed to integrate the necessary information about materials used in the product, and such information can be accessed and used at any point in the life cycle, from design to disposal. In the article, we present how PDT can support life cycle assessment (LCA) by focusing on a series of standards for communicating data for design and manufacture and standards for business and commercial information. Examples of possibilities for using PDT and semantic web for LCA data are introduced. The findings presented here are based on DEPUIS (Design of Environmentally‐Friendly Products Using Information Standards), a project aimed at improving the eco‐design of new products and services through the innovative use of new information standards.  相似文献   

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全新结构药物的研发存在周期长、耗资大、风险高的问题.通过各种技术预测已有药物的新适应症,即药物重定位,可以缩短药物研发时间、降低研发成本和风险.由于疾病种类和已知药物的数量繁多,完全通过实验筛选已知药物的新用途仍然具有很高的成本.随着组学和药物信息学数据的积累,药物重定位进入到了理性设计和实验筛选相结合的阶段,药物重定位的计算预测已经成为计算生物学和系统生物学的重要研究方向.本文将目前药物重定位计算分析的策略归纳为药物-靶标关系分析、药物-药物关系分析和药物-疾病关系分析,对已报道的技术方法及其成功应用实例进行了综述.  相似文献   

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在当前中国按病种付费支付方式推行受阻的背景下,针对改革中存在的关键问题,应用文献荟萃分析的方法,并结合在医疗卫生领域逐渐成熟的应用,推导出从理论及方法学的适用性和实践中的可操作性层面,数据挖掘聚类技术均可有效解决当前支付方式改革标准难以制定的困境,以期为决策者提供理论支撑。  相似文献   

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目的 采取有效的防范措施,最大限度地减少医院内跌倒和因跌倒导致的伤害事件的发生。方法 对跌倒事件采用柏拉图分析法进行分析,区分“少数重点因素”和“大量微细因素”。结果 病人的身心疾病、病人独自行动以及病人不愿求助和不安全的环境是防范病人跌倒时尤其要关注的因素。结论 根据柏拉图分析法,修订病人跌倒/坠床危险因子评估表,落实个体化的跌倒防范措施,营造安全的设施及环境,加强病人及家属的教育,有助于防范医院内病人跌倒的发生。  相似文献   

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细胞组学(cytomics)是一门基于细胞分析技术的科学,它是在细胞水平对生物体系的研究,具有真实、简单和系统性的特点,在生物医学研究中有很好的应用前景。现对细胞组学的概念、特点和内容进行介绍,并结合药物研发的现状和过程,综述了细胞组学在药物研发各阶段的应用,最后对其前景进行了展望。  相似文献   

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DNA molecular weight standards (DNA markers, nucleic acid ladders) are commonly used in molecular biology laboratories as references to estimate the size of various DNA samples in electrophoresis process. One method of DNA marker production is digestion of synthetic vectors harboring multiple DNA fragments of known sizes by restriction enzymes. In this article, we described three novel strategies—sequential DNA fragment ligation, screening of ligation products by polymerase chain reaction (PCR) with end primers, and “small fragment accumulation”—for constructing complex synthetic vectors and minimizing the mass differences between DNA fragments produced from restrictive digestion of synthetic vectors. The strategy could be applied to construct various complex synthetic vectors to produce any type of low-range DNA markers, usually available commercially. In addition, the strategy is useful for single-step ligation of multiple DNA fragments for construction of complex synthetic vectors and other applications in molecular biology field. Zhe Chen and Jianbing Wu contributed to this work equally.  相似文献   

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细胞药物最终用于人体,必须建立相应的质量标准,进行质量控制。系统地贯彻到供者筛查、组织采集、细胞分离、培养、冻存、复苏、放行、运输、使用等全过程,确保产品的安全性、有效性和稳定性。近年来,我国逐渐改变了把细胞治疗作为第三类医疗技术管理的思路。一方面,已有第三类医疗技术取消行政审批;另一方面,又把除自体外的干细胞移植纳入药物管理,并建立了相应的质量标准和质量管理办法。  相似文献   

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There exists a crisis in the delivery of medical services, particularly by family doctors of whom there is an apparent shortage.A study of family practice in Kingston, Ontario, and in the nearby countryside indicates three critical needs in family practice: professional assistants for the family doctors, efficient office facilities and new methods of delivering family medical care in rural areas. The Faculty of Medicine at Queen''s University has involved itself in a study of these matters and is developing a program to help solve them, by research into the nature of the problems and into methods for alleviating them, by keeping practising physicians informed through research reports and the continuing education program of the Medical School, by the development of pilot projects, and by the evaluation of new services aimed at these problems, independently launched by physicians in the community. Pilot projects to date include two designed to study the use of registered nurses as doctor assistants and another which involves the organization and operation of a university-sponsored community health centre. Last, but by no mean least, the Provincial Government is continually briefed on all these activities.  相似文献   

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生物信息学的飞速发展为药物开发提供了新的手段,计算机辅助药物设计是多学科交叉发展的产物。结合近些年来的一些成功实例,对数据库搜寻、计算机直接生成(全新药物设计)和进一步优化等计算机辅助药物设计技术及相关重要算法软件的新进展做一综述。  相似文献   

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信号适体兼具有分子识别和信号转导的功能.从随机寡核苷酸库中筛选出的适体,要经过合理设计和筛选后修饰,才具备信号转导功能.信号适体可分为标记和非标记两大类.本文着重介绍荧光标记信号适体的设计策略,包括基于荧光偏振分析标记一个荧光基团,及基于荧光共振能量转移同时标记荧光基团、淬灭基团,或两个荧光基团的信号适体(包括分子信标适体、结构转换和原位标记信号适体).非标记信号适体的设计,有嵌合法、置换法、光转换复合物法,及适体-多聚物偶联法.此外,亦可直接从体外筛选出信号适体.信号适体的诸多优点利于其用于生物传感器及均相液相中实时蛋白识别与定量分析.  相似文献   

13.
M. Kimmel  D. E. Axelrod 《Genetics》1990,125(3):633-644
An increased number of copies of specific genes may offer an advantage to cells when they grow in restrictive conditions such as in the presence of toxic drugs, or in a tumor. Three mathematical models of gene amplification and deamplification are proposed to describe the kinetics of unstable phenotypes of cells with amplified genes. The models differ in details but all assume probabilistic mechanisms of increase and decrease in gene copy number per cell (gene amplification/deamplification). Analysis of the models indicates that a stable distribution of numbers of copies of genes per cell, observed experimentally, exists only if the probability of deamplification exceeds the probability of amplification. The models are fitted to published data on the loss of methotrexate resistance in cultured cell lines, due to the loss of amplified dihydrofolate reductase gene. For two mouse cell lines unstably resistant to methotrexate the probabilities of amplification and deamplification of the dihydrofolate reductase gene on double minute chromosomes are estimated to be approximately 2% and 10%, respectively. These probabilities are much higher than widely presumed. The models explain the gradual disappearance of the resistant phenotype when selective pressure is withdrawn, by postulating that the rate of deamplification exceeds the rate of amplification. Thus it is not necessary to invoke a growth advantage of nonresistant cells which has been the standard explanation. For another analogous process, the loss of double minute chromosomes containing the myc oncogene from SEWA tumor cells, the growth advantage model does seem to be superior to the amplification and deamplification model. In a more theoretical section of the paper, it is demonstrated that gene amplification/deamplification can result in reduction to homozygosity, such as is observed in some tumors. Other applications are discussed.  相似文献   

14.
Autoimmune diseases reflect a breakdown in self-tolerance that results from defects in thymic deletion of potentially autoreactive T cells (central tolerance) and in T-cell intrinsic and extrinsic mechanisms that normally control potentially autoreactive T cells in the periphery (peripheral tolerance). The mechanisms leading to autoimmune diseases are multifactorial and depend on a complex combination of genetic, epigenetic, molecular, and cellular elements that result in pathogenic inflammatory responses in peripheral tissues driven by self-antigen-specific T cells. In this article, we describe the different checkpoints of tolerance that are defective in autoimmune diseases as well as specific events in the autoimmune response which represent therapeutic opportunities to restore long-term tolerance in autoimmune diseases. We present evidence for the role of different pathways in animal models and the therapeutic strategies targeting these pathways in clinical trials in autoimmune diseases.Autoimmune diseases are debilitating conditions that affect a large and growing portion of the population (∼3%–5% in the United States) (Jacobson et al. 1997). Autoimmune diseases take a devastating toll on affected families and have a considerable economic impact. Thus, improving the understanding of autoimmune diseases and developing novel therapies have been significant goals in public health. The development of autoimmune diseases reflects a loss of tolerance of the immune system for self-antigens. With the exception of a few rare monogenic diseases such as immune dysregulation, polyendocrinopathy, enteropathy, X-linked syndrome (IPEX), and autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED) syndrome, the development of autoimmunity is a complex and multifactorial process. This process usually involves genetic predispositions and poorly defined environmental factors that result in slight alterations in many different checkpoints, which in turn tilts the balance toward autoreactivity and away from immunoregulation. Although clearly there are key roles for B cells, antigen-presenting cells (APCs), and the innate immune response in the development and progression of autoimmune diseases, this article will focus on autoreactive T cells and potential targets of tolerogenic treatments (Fig. 1). In addition, we will discuss selected strategies currently available or being developed in the clinic as well as future opportunities to prevent and treat these diseases. Finally, current clinical strategies available as the standard of care for autoimmune diseases rely on immunosuppressive and anti-inflammatory treatments that curtail the pathological events, alleviate symptoms, and provide short-term relief in some patients. Thus, we will focus for the most part on immunotherapies aimed at reestablishing long-term tolerance.Open in a separate windowFigure 1.Development of the pathogenic autoimmune response and targets for immunotherapy. Autoreactive T cells that escape thymic negative selection are usually controlled by intrinsic (inhibitory receptors) and extrinsic (regulatory cell populations) mechanisms of tolerance in the periphery. In individuals genetically prone to autoimmunity, one or several of these checkpoints are defective, resulting in expansion of autoreactive T cells that cannot be controlled by Tregs (red, autoreactive effector T cells; green, Tregs; gray, polyclonal conventional T cells). Autoreactive T cells migrate to their targeted tissue where cytotoxic mechanisms and uncontrolled inflammation mediated by soluble mediators released by T cells and innate cells result in tissue damage. Various immunotherapeutic strategies target different steps in this process. (A) The ultimate goal of immunotherapy is to alter the balance of pathogenic versus regulatory T cells to restore tolerance, as detailed in Figure 2. (B) Anti-CD3 mAbs, antigen-specific therapies, and costimulation blockade alter the interactions between autoreactive T cells and antigen-presenting cells (APCs) and/or the signaling pathways resulting from productive T-cell receptor (TCR) ligation after presentation of cognate self-peptide/MHC (major histocompatibility complexes) in the presence of costimulatory signals, leading to deletion, anergy, immune deviation, or induction of Tregs. (C) Many strategies aim at boosting Tregs, either by concomitantly deleting Teff and promoting Tregs, and thus resetting the immune system to various degrees, such as antithymocyte globulin (ATG), rapamycin plus IL-2, and autologous hematopoietic stem cell transplantation (HSCT), or directly providing Tregs through cellular therapy. (D,E) Some therapies target populations of APCs, such as depletion of B cells by rituximab or the promotion of self-antigen presentation specifically by tolerogenic dendritic cells (DCs). (F) The migration of autoreactive T cells to their target tissue is being altered by inhibitors of leukocyte trafficking such as natalizumab and fingolimod. These drugs may further promote tolerance by keeping autoreactive T cells in the lymph nodes (LN) during immunosuppression, a prerequisite for efficient immunomodulation in some cases. (G) Anti-inflammatory therapies such as tumor necrosis factor (TNF) antagonists reduce tissue damage but also create an immunological environment more favorable to the induction of Tregs and restoration of tolerance.  相似文献   

15.
Impairment of endothelial nitric oxide synthase (eNOS) activity is implicated in the pathogenesis of endothelial dysfunction in many diseases including ischaemic stroke. The modulation of eNOS during and/or following ischaemic injury often represents a futile compensatory mechanism due to a significant decrease in nitric oxide (NO) bioavailability coupled with dramatic increases in the levels of reactive oxygen species that further neutralise NO. However, applications of a number of therapeutic agents alone or in combination have been shown to augment eNOS activity under a variety of pathological conditions by potentiating the expression and/or activity of Akt/eNOS/NO pathway components. The list of these therapeutic agents include NO donors, statins, angiotensin-converting enzyme inhibitors, calcium channel blockers, phosphodiesterase-3 inhibitors, aspirin, dipyridamole and ellagic acid. While most of these compounds exhibit anti-platelet properties and are able to up-regulate eNOS expression in endothelial cells and platelets, others suppress eNOS uncoupling and tetrahydrobiopterin (an eNOS stabiliser) oxidation. As the number of therapeutic molecules that modulate the expression and activity of eNOS increases, further detailed research is required to reveal their mode of action in preventing and/or reversing the endothelial dysfunction.  相似文献   

16.
海藻酸钠壳聚糖微球是具有生物粘附性且能结合和传递大分子药物的天然高分子材料,且在生物医学领域具有广阔应用前景的药物载体。它具有生物黏附性、生物相容性、生物可降解性、对人体无毒性且能够结合和传递大分子药物的天然高分子材料。海藻酸钠壳聚糖微球作为载药微球具有提高药物的生物利用度、延长药物的作用时间等优点。国内外近些年已将其应用于药剂学领域,以及将其作为药物载体经微球化与药物结合形成给药系统的研究也在逐步开展并取得了较多成果。本文主要阐述海藻酸钠壳聚糖微球的主要生物特性、作用特点及其在医学领域中应用的研究进展,并对其应用前景进行探讨。  相似文献   

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Two primary regulatory mechanisms have been proposed to incentivize new antibiotic development: (1) changing Food and Drug Administration (FDA) approval processes to expedite antibiotic approval; and (2) offering enhanced possibilities for market exclusivity. Changes to the FDA regulatory approval process include greater reliance on surrogate endpoints such as biomarkers, use of noninferiority hypothesis designs for key preapproval clinical trials, and development of an expedited development track specific for antibiotics called the Limited Population pathway. The second strategy intended to encourage new antibiotic development has been to provide additional market exclusivity incentives based on regulatory approval. While these pathways have some positive attributes, they also present enhanced risks to patients associated with lower regulatory barriers and the market exclusivity incentives may not efficiently direct resources to the true origins of antibiotic innovation.  相似文献   

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金纳米粒是一种新型纳米载体,具有独特的理化、光学和生物学性质,且具有低毒性、低免疫原性、生物相容性好、体表面积大、易制备、粒径和形态可控、表面易修饰等优点,在生物医学领域和药物传递系统中具有广阔的应用前景。综述金纳米粒在小分子药物和基因药物传递系统中的应用研究新进展。  相似文献   

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