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41.
Almost all tumors are composed of a heterogeneous cell population, making them difficult to treat. A small cancer stem cell population with a low proliferation rate and a high tumorigenic potential is thought to be responsible for cancer development, metastasis and resistance to therapy. Stem cells were reported to be involved in both normal development and carcinogenesis, some molecular mechanisms being common in both processes. No less controversial, stem cells are considered to be important in treatment of malignant diseases both as targets and drug carriers. The efforts to understand the role of different signalling in cancer stem cells requires in depth knowledge about the mechanisms that control their self-renewal, differentiation and malignant potential. The aim of this paper is to discuss insights into cancer stem cells historical background and to provide a brief review of the new therapeutic strategies for targeting cancer stem cells.  相似文献   
42.
In order to develop mass customization, many companies use configuration software to customize their products. Although many studies already exist about Product Configuration, Requirements and Process Configuration have not been studied in detail. As all these three aspects must be considered for mass customization, the aim of this paper is to show how Product Configuration, when considered as a constraint satisfaction problem, can be extended upstream towards Requirements Configuration and downstream towards Process Configuration. Product Configuration basics are first reviewed thanks to a constraint based approach, and an analysis of industrial configuration situations is done in order to clarify mass customization needs in terms of configuration. Then upstream Requirements Configuration and downstream Process Configuration are defined and generic models are proposed. It is shown that the proposed elements allow a global and consistent flow of configuration activities. A detailed example illustrates the different configuration problems and a discussion terminates the paper.  相似文献   
43.
In advanced methods of delineation and mapping of scientific fields, hybrid methods open a promising path to the capitalisation of advantages of approaches based on words and citations. One way to validate the hybrid approaches is to work in cooperation with experts of the fields under scrutiny. We report here an experiment in the field of genomics, where a corpus of documents has been built by a hybrid citation-lexical method, and then clustered into research themes. Experts of the field were associated in the various stages of the process: lexical queries for building the initial set of documents, the seed; citation-based extension aiming at reducing silence; final clustering to identify noise and allow discussion on border areas. The analysis of experts’ advices show a high level of validation of the process, which combines a high-precision and low-recall seed, obtained by journal and lexical queries, and a citation-based extension enhancing the recall. This findings on the genomics field suggest that hybrid methods can efficiently retrieve a corpus of relevant literature, even in complex and emerging fields.  相似文献   
44.
在狭窄的长形场地上建造房子具有一定的难度,而在维也纳郊区的小斜坡上修建住宅区更是难上加难,林木繁茂的陡峭崖径把道路和建筑用地分隔开来,为设计增添了新的难题.  相似文献   
45.
旅行花园     
一位"植物猎人"在维也纳第三区的一个公寓屋顶创造了他的天堂。公寓的主人同意他暂时使用屋顶,但必须保证使用期限到时,花园可以容易地进行清理。一个低造价的简易软木结构牢固地悬挂在屋顶上,这样负荷就不会直接传给下面的屋顶。冬天来临时,可以用背包把花盆里的植物搬到屋子里。背包其实是一种叫做"Buckelkraxen"的传统搬运工具,它常为奥地利阿尔卑斯山上的农夫们所使用。因此,除了少数种类外,大多数植物只有在夏天的时候,才会留在屋顶上。这个花园还有另外一个好处:园丁可以随性改变植物的摆放位置。设计者筛选植物的最重要标准是香味、气氛和  相似文献   
46.
Variants of the TTLL5 gene, which encodes tubulin tyrosine ligase-like family member five, are a rare cause of cone dystrophy (COD) or cone-rod dystrophy (CORD). To date, only a few TTLL5 patients have been clinically and genetically described. In this study, we report five patients harbouring biallelic variants of TTLL5. Four adult patients presented either COD or CORD with onset in the late teenage years. The youngest patient had a phenotype of early onset severe retinal dystrophy (EOSRD). Genetic analysis was performed by targeted next generation sequencing of gene panels and assessment of copy number variants (CNV). We identified eight variants, of which six were novel, including two large multiexon deletions in patients with COD or CORD, while the EOSRD patient harboured the novel homozygous p.(Trp640*) variant and three distinct USH2A variants, which might explain the observed rod involvement. Our study highlights the role of TTLL5 in COD/CORD and the importance of large deletions. These findings suggest that COD or CORD patients lacking variants in known genes may harbour CNVs to be discovered in TTLL5, previously undetected by classical sequencing methods. In addition, variable phenotypes in TTLL5-associated patients might be due to the presence of additional gene defects.  相似文献   
47.
48.
We classify and analyze bit errors in the current measurement mode of the Kirchhoff-law–Johnson-noise (KLJN) key distribution. The error probability decays exponentially with increasing bit exchange period and fixed bandwidth, which is similar to the error probability decay in the voltage measurement mode. We also analyze the combination of voltage and current modes for error removal. In this combination method, the error probability is still an exponential function that decays with the duration of the bit exchange period, but it has superior fidelity to the former schemes.  相似文献   
49.
Reading books can serve as a means of gathering information, relaxing and escaping daily stress. Although reading is often primarily an individual activity, many readers also enjoy sharing reading experiences with friends, relatives, colleagues and, through the internet, even with strangers. Apart from valuing these individual and collective book activities, books as physical artifacts are also valued, for example because of the memories associated with them. This paper investigates how books can be enhanced with a new product, system or service. In a qualitative interview study, the main reasons for valuing books were found to be related to the self (individual activities and feelings), experiences (e.g., enjoyment or release) and personal values (e.g., embodiment of ideals or personification). As a result, it was decided for the remainder of this study to focus on communication about books, because in addition to individual book-related activities and feelings, users indicated to communicate about books a lot. A book community Web site, called Shelf, was developed to investigate whether book communication could be increased by facilitating an online community and whether users would appreciate the Web site functionality. Shelf was used in a 14-day user evaluation, and it was concluded that the Web site increased the extent to which readers communicated about books. We expect that such an online book community would be a valuable enhancement of current book customs, in particular in combination with the current e-book trend, for various types of readers who would like to share their experiences.  相似文献   
50.
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