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1.
Tumor Markers comprise a wide spectrum of biomacromolecules synthesized in excess concentration by a wide variety of neoplastic cells. The markers could be endogenous products of highly active metabolic malignant cells or the products of newly switched on genes, which remained unexprssed in early life or newly acquired antigens at cellular and sub-cellular levels. The appearance of tumor marker and their concentration are related to the genesis and growth of malignant tumors in patients. An ideal tumor marker should be highly sensitive, specific, reliable with high prognostic value, organ specificity and it should correlate with tumor stages. However, none of the tumor markers reported to date has all these characteristics. Inspite of these limitations, many tumor markers have shown excellent clinical relevance in monitoring efficacy of different modes of therapies during entire course of illness in cancer patients. Additionally, determination of markers also helps in early detection of cancer recurrence and in prognostication.  相似文献   

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当代情报学理论思潮:实用主义   总被引:2,自引:0,他引:2  
哲学对情报学有重要意义,每一种情报学理论都有其相应的哲学基础。首先,分析了实用主义的概况,归纳了古典实用主义和新实用主义的主要哲学观点。其次,分析了实用主义在认识论上的一些主要观点,包括实用主义对知识、符号和意义的认识和理解,在分析这些观点的同时探讨了其对情报学概念和现象的影响,如信息的定义、信息过程、情报学研究方法等。最后,基于实用主义认识论构建了情报学理论的初步框架。  相似文献   

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《Research Policy》2022,51(2):104447
In the past decade, coworking spaces have emerged as a new and promising phenomenon within entrepreneurship. Due to its prevalence, popularity, and potential for disruptive change, coworking is increasingly relevant to theory, practice, and policy in entrepreneurship, yet its implications are largely unstudied given the rapid rise of the phenomenon. Overall, more research is needed to inform owners, policy makers, and entrepreneurs regarding the effects of this new organizational form. This study takes an exploratory empirical approach with the goal of shedding light on the current landscape of coworking. By so doing, I provide an initial foundation for research on the coworking movement in entrepreneurship and the various research streams it can enrich.  相似文献   

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A microgrid (MG) is a building block of future smart grid, it can be defined as a network of low voltage power generating units, storage devices and loads. System of systems (SoS) is another concept involving large scale integration of various systems. In this paper, we provide an overview of recent developments in modeling and control methods of microgrid as well as presenting the reason towards incorporating MG into the existing grid. Various SoS control strategies when applied to MG are discussed.  相似文献   

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The neoplastic proliferation of single clones of plasma cells causes synthesis of very large amount of monoclonal immunoglobulins consisting of only one type of heavy either the gamma, alpha, mu, delta or epsilon chain or only kappa or lambda light chains. Each monoclonal immunolobulin differs idiotypically from each other. These monoclonal immunoglobulins are also called paraproteins and are frequently associated with a broad heterogeneous group of plasma cell dyscrasias. Occasionally their presence is observed in a few benign conditions and in old age. In the present review a detailed account of different types of monoclonal gammapathies are described.  相似文献   

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农业系统恢复力研究进展综述   总被引:3,自引:0,他引:3  
李晓  周丁扬 《资源科学》2015,37(9):1747-1754
恢复力作为社会-生态系统的一个重要属性,是复杂系统实施可持续发展的重要途径之一。在已有认识和研究成果的基础上,本文首先概述了关于恢复力及农业系统恢复力概念的观点。然后从农业系统恢复力的影响因素、农业系统恢复力评价和农业系统恢复力研究的尺度效应三方面梳理了近年来国内外的研究进展,从自然因素(水资源、土地资源和气候资源)和社会因素(经济状况、资源管理制度和社会特征等)两方面总结了影响农业系统恢复力的因素,探讨了时间尺度和空间尺度对农业系统恢复力的影响,从定性和定量评价两方面归纳了农业系统恢复力的度量方法。进而指出未来中国农业系统恢复力的研究应注重采用多尺度多过程耦合分析以及量化分析,加强对半干旱区以外气候变化较脆弱地区的研究,并且关注社会因素在农业系统恢复力中的作用。  相似文献   

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This paper presents an overview of automatic methods for building domain knowledge structures (domain models) from text collections. Applications of domain models have a long history within knowledge engineering and artificial intelligence. In the last couple of decades they have surfaced noticeably as a useful tool within natural language processing, information retrieval and semantic web technology. Inspired by the ubiquitous propagation of domain model structures that are emerging in several research disciplines, we give an overview of the current research landscape and some techniques and approaches. We will also discuss trade-offs between different approaches and point to some recent trends.  相似文献   

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作为行为理论体系的一个分支,行为控制理论研究近年来逐步成为一个热点。它基本遵循心理学和管理学行为控制研究两条基本路径,尤以管理学对行为控制研究为主。行为控制领域涉及企业行为、政府行为以及教育领域等。在以人为本的21世纪,行为控制理论拥有较大的发展空间,呈现学科交叉化、理论体系化和方法模型化的趋势。  相似文献   

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文章对实用主义与技术哲学国际会议的议题与内容进行了梳理,主要阐述了国外实用主义技术哲学研究的动态和趋势,并就拉里·希克曼(Larry Hckman)、安德鲁·费恩伯格(Andrew Feenberg)、唐·伊德(Don Ihde)及村田纯一(Junichi Murata)对约翰·杜威(John Dewey)的技术哲学思想的不同解析加以述评.  相似文献   

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Over the recent years, the growth of online social media has greatly facilitated the way people communicate with each other. Users of online social media share information, connect with other people and stay informed about trending events. However, much recent information appearing on social media is dubious and, in some cases, intended to mislead. Such content is often called fake news. Large amounts of online fake news has the potential to cause serious problems in society. Many point to the 2016 U.S. presidential election campaign as having been influenced by fake news. Subsequent to this election, the term has entered the mainstream vernacular. Moreover it has drawn the attention of industry and academia, seeking to understand its origins, distribution and effects.Of critical interest is the ability to detect when online content is untrue and intended to mislead. This is technically challenging for several reasons. Using social media tools, content is easily generated and quickly spread, leading to a large volume of content to analyse. Online information is very diverse, covering a large number of subjects, which contributes complexity to this task. The truth and intent of any statement often cannot be assessed by computers alone, so efforts must depend on collaboration between humans and technology. For instance, some content that is deemed by experts of being false and intended to mislead are available. While these sources are in limited supply, they can form a basis for such a shared effort.In this survey, we present a comprehensive overview of the finding to date relating to fake news. We characterize the negative impact of online fake news, and the state-of-the-art in detection methods. Many of these rely on identifying features of the users, content, and context that indicate misinformation. We also study existing datasets that have been used for classifying fake news. Finally, we propose promising research directions for online fake news analysis.  相似文献   

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Probabilistic topic models are unsupervised generative models which model document content as a two-step generation process, that is, documents are observed as mixtures of latent concepts or topics, while topics are probability distributions over vocabulary words. Recently, a significant research effort has been invested into transferring the probabilistic topic modeling concept from monolingual to multilingual settings. Novel topic models have been designed to work with parallel and comparable texts. We define multilingual probabilistic topic modeling (MuPTM) and present the first full overview of the current research, methodology, advantages and limitations in MuPTM. As a representative example, we choose a natural extension of the omnipresent LDA model to multilingual settings called bilingual LDA (BiLDA). We provide a thorough overview of this representative multilingual model from its high-level modeling assumptions down to its mathematical foundations. We demonstrate how to use the data representation by means of output sets of (i) per-topic word distributions and (ii) per-document topic distributions coming from a multilingual probabilistic topic model in various real-life cross-lingual tasks involving different languages, without any external language pair dependent translation resource: (1) cross-lingual event-centered news clustering, (2) cross-lingual document classification, (3) cross-lingual semantic similarity, and (4) cross-lingual information retrieval. We also briefly review several other applications present in the relevant literature, and introduce and illustrate two related modeling concepts: topic smoothing and topic pruning. In summary, this article encompasses the current research in multilingual probabilistic topic modeling. By presenting a series of potential applications, we reveal the importance of the language-independent and language pair independent data representations by means of MuPTM. We provide clear directions for future research in the field by providing a systematic overview of how to link and transfer aspect knowledge across corpora written in different languages via the shared space of latent cross-lingual topics, that is, how to effectively employ learned per-topic word distributions and per-document topic distributions of any multilingual probabilistic topic model in various cross-lingual applications.  相似文献   

14.
The increasing demand for propionic acid (PA) production and its wide applications in several industries, especially the food industry (as a preservative and satiety inducer), have led to studies on the low-cost biosynthesis of this acid. This paper gives an overview of the biotechnological aspects of PA production and introduces Propionibacterium as the most popular organism for PA production. Moreover, all process variables influencing the production yield, different simple and complex carbon sources, the metabolic pathway of production, engineered mutants with increased productivity, and modified tolerance against high concentrations of acid have been described. Furthermore, possible methods of extraction and analysis of this organic acid, several applied bioreactors, and different culture systems and substrates are introduced. It can be concluded that maximum biomass and PA production may be achieved using metabolically engineered microorganisms and analyzing the most significant factors influencing yield. To date, the maximum reported yield for PA production is 0.973 g·g-1, obtained from Propionibacterium acidipropionici in a three-electrode amperometric culture system in medium containing 0.4 mM cobalt sepulchrate. In addition, the best promising substrate for PA bioproduction may be achieved using glycerol as a carbon source in an extractive continuous fermentation. Simultaneous production of PA and vitamin B12 is suggested, and finally, the limitations of and strategies for competitive microbial production with respect to chemical process from an economical point of view are proposed and presented. Finally, some future trends for bioproduction of PA are suggested.  相似文献   

15.
Apoptosis a physiological mechanism that eliminates excessive, damaged or unwanted cells, is a highly regulated pathway important for maintaining homeostasis in multicellular organisms. It can be initiated through various signals via the extrinsic pathway which involves death receptors, or via the intrinsic pathway which is initiated by intracellular damage and involves the mitochondria and release of cytochrome c from it to further activate caspases. The Bcl-2 family of proteins is situated upstream to the irreversible damage of cellular constituents and is an important checkpoint in the fate of a cell. The pro-apoptotic members, BH3 only members include BID, BAD and BIM. They directly or indirectly activate multidomain BAX/BAK that constitute the requisite gateway to the intrinsic pathway which operates at the mitochondrial surface and endoplasmic reticulum. In contrast, antiapoptotic members such as Bcl-2, Bcl-XL bind and sequester activation. Downstream of mitochondria, the apoptosome involvement is seen to generate caspase activity. Post mitochondria regulation involves IAPs, and their inhibitors. The pathogenesis of several diseases such as cancer, neurodegenerative disorders, autoimmune disorders, heart disease, infectious diseases including AIDS is closely related to aberrant apoptosis. Consequently interest has emerged in employing various the rapeutic approaches such as gene therapy, antisense therapy, recombinant biologicals, organic and combinatorial chemistry, to specifically target apoptosis signaling pathways such as death receptors FAS/TRAIL, Bcl-2, p53, IAPs, SMAC and caspases, etc. and are now advancing from preclinical to clinical phase.  相似文献   

16.
An overview of information ethics issues in a world-wide context   总被引:2,自引:0,他引:2  
This article presents an overview of significant issues facing contemporary information professionals. As the world of information continues to grow at unprecedented speed and in unprecedented volume, questions must be faced by information professionals. Will we participate in the worldwide mythology of equal access for all, or will we truly work towards this debatable goal? Will we accept the narrowing of choice for our corresponding increasing diverse clientele? Such questions must be considered in a holistic context and an understanding of the many levels of information inequities is requisite. Beginning with an historical perspective, Buchanan presents Mustapha Masmoudi's seminal review of forms of information inequities. She then describes qualitative forms of inequities, such as information imperialism and cultural bias embedded in such practices as cataloging and classification. Following, a review of quantitative inequities is presented. Such issues as the growing commoditization of information and information services demand attention from the ethical perspective. And, finally, the Internet and implications surrounding the world-wide dissemination of information is discussed. The article concludes with an extraction form Richard Sclove's Democracy and Technology, and asks that we as information professionals actively examine the information industry around us and demand a more democratic process within which to work.  相似文献   

17.
Prior art patent citations have become a popular measure of patent quality and knowledge flow between firms. Interpreting these measurements is complicated, in some cases, because prior art citations are added by patent examiners as well as by patent applicants. The U.S. Patent and Trademark Office (USPTO) adopted new reporting procedures in 2001, making it possible to measure examiner and applicant citations separately for the first time. We analyzed prior art citations listed in all U.S. patents granted in 2001-2003, and found that examiners played a significant role in identifying prior art, adding 63% of citations on the average patent, and all citations on 40% of patents granted. An analysis of variance found that firm-specific variables explain most of the variation in examiner-citation shares. Using multivariate regression, we found that foreign applicants to the USPTO had the highest proportion of citations added by examiners. High-volume patent applicants had a greater proportion of examiner citations, and a substantial number of firms won patents without listing a single applicant citation. In terms of technology, we found higher examiner shares among patents in electronics, communications, and computer-related fields. Taken together, our findings suggest that firm-level patenting practices, particularly among high-volume applicants, have a strong influence on citation data and merit additional research.  相似文献   

18.
Concerns have been raised that the growing emphasis on the commercial value of academic research may have negative, unintended consequences, notably that it may have a deleterious effect on the production and dissemination of scientific knowledge or on the open-ended nature of public science. These concerns have catalyzed an expanding set of empirical studies, the evidence from which is vast and mixed. We review this body of investigative work, teasing out some preliminary conclusions regarding the broader implications of academic enterprise and promising avenues for further research.  相似文献   

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本刊讯2007年3月19—21日,中国科学院2007年度工作会议在北京召开。中国科学院常务副院长白春礼代表中科院党组、院务会议,在开幕式上做了题为《建设改革创新和谐奋进的中国科学院为构建社会主义和谐社会做贡献》的工作报告。  相似文献   

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近些年来 ,我院的基础科学研究取得了较大进展 ,特别是实施知识创新工程试点工作以来 ,在院、所两个层次凝练和提升科技创新目标 ,进行了建院以来涉及面最广、意义最为深远的学科布局和组织机构调整 ,在转换运行机制、凝聚优秀人才等方面做了大量工作 ,提高了科技竞争力 ,调动了科技人员的积极性 ,推动了基础科学研究工作的发展。本刊将分期介绍近年来取得的成果。  相似文献   

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