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21.
Familial clustering studies indicate that breast cancer risk has a substantial genetic component. To identify new breast cancer risk variants, we genotyped approximately 300,000 SNPs in 1,600 Icelandic individuals with breast cancer and 11,563 controls using the Illumina Hap300 platform. We then tested selected SNPs in five replication sample sets. Overall, we studied 4,554 affected individuals and 17,577 controls. Two SNPs consistently associated with breast cancer: approximately 25% of individuals of European descent are homozygous for allele A of rs13387042 on chromosome 2q35 and have an estimated 1.44-fold greater risk than noncarriers, and for allele T of rs3803662 on 16q12, about 7% are homozygous and have a 1.64-fold greater risk. Risk from both alleles was confined to estrogen receptor-positive tumors. At present, no genes have been identified in the linkage disequilibrium block containing rs13387042. rs3803662 is near the 5' end of TNRC9 , a high mobility group chromatin-associated protein whose expression is implicated in breast cancer metastasis to bone.  相似文献   
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Cognitive Science is a promising field of research that deals with one of the most fundamental questions ever: how do beings know? However, despite the long and extensive tradition of the field it has not yet become an area of knowledge with scientific identity. This is primarily due to three reasons: the lack of boundaries in defining the object of study, i.e. cognition, the lack of a precise, robust and consistent scientific methodology and results, and the inner problems derived from its interdisciplinary nature. This paper presents a background review, a theoretical frame and a humble reflection on these topics in order to arouse the internal debate among readers once more.  相似文献   
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Summary Responses to iontophoretic NA were increased in hyperthyroid rats and decreased in hypothyroid animals. No effect was observed on acetylcholine and glycine responses tested in the same way.This work was aided by grants from Consejo de Desarrollo Cientifico y Humanistico U.C.V. and CONICIT proyecto 51.26.SI-086.  相似文献   
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Functional interplay between tetraspanins and proteases   总被引:1,自引:1,他引:0  
Several recent publications have described examples of physical and functional interations between tetraspanins and specific membrane proteases belonging to the TM-MMP and α-(ADAMs) and γ-secretases families. Collectively, these examples constitute an emerging body of evidence supporting the notion that tetraspanin-enriched microdomains (TEMs) represent functional platforms for the regulation of key cellular processes including the release of surface protein ectodomains ("shedding"), regulated intramembrane proteolysis ("RIPing") and matrix degradation and assembly. These cellular processes in turn play a crucial role in an array of physiological and pathological phenomena. Thus, TEMs may represent new therapeutical targets that may simultaneously affect the proteolytic activity of different enzymes and their substrates. Agonistic or antagonistic antibodies and blocking soluble peptides corresponding to tetraspanin functional regions may offer new opportunities in the treatment of pathologies such as chronic inflammation, cancer, or Alzheimer's disease. In this review article, we will discuss all these aspects of functional regulation of protease activities by tetraspanins.  相似文献   
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Interleukin (IL)-1 is a proinflammatory cytokine with important roles in innate immunity, as well as in normal tissue homeostasis. Interestingly, recent studies have also shown IL-1 to function in the dynamics of the actin cytoskeleton and cell junctions. For example, treatment of different epithelia with IL-1α often results in the restructuring of the actin network and cell junctions, thereby leading to junction disassembly. In this review, we highlight new and interesting findings that show IL-1 to be a critical player of restructuring events in the seminiferous epithelium of the testis during spermatogenesis.  相似文献   
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To identify new risk variants for cutaneous basal cell carcinoma, we performed a genome-wide association study of 16 million SNPs identified through whole-genome sequencing of 457 Icelanders. We imputed genotypes for 41,675 Illumina SNP chip-typed Icelanders and their relatives. In the discovery phase, the strongest signal came from rs78378222[C] (odds ratio (OR) = 2.36, P = 5.2 × 10(-17)), which has a frequency of 0.0192 in the Icelandic population. We then confirmed this association in non-Icelandic samples (OR = 1.75, P = 0.0060; overall OR = 2.16, P = 2.2 × 10(-20)). rs78378222 is in the 3' untranslated region of TP53 and changes the AATAAA polyadenylation signal to AATACA, resulting in impaired 3'-end processing of TP53 mRNA. Investigation of other tumor types identified associations of this SNP with prostate cancer (OR = 1.44, P = 2.4 × 10(-6)), glioma (OR = 2.35, P = 1.0 × 10(-5)) and colorectal adenoma (OR = 1.39, P = 1.6 × 10(-4)). However, we observed no effect for breast cancer, a common Li-Fraumeni syndrome tumor (OR = 1.06, P = 0.57, 95% confidence interval 0.88-1.27).  相似文献   
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At the end of their product life cycle, tires require special handling and treatment in order to avoid damaging the environment and society. Reverse Logistics (RL) is necessary to manage this type of solid waste. In Brazilian cities, collection is one of the bottlenecks. One of the main difficulties in this process is enabling joint-action between the main stakeholders: Final consumers, the government and private companies. The main objective of this paper is to identify e implement opportunities for improvement in the collection phase of end-of-life tires through action-research, involving simultaneous participation between public and private organizations. The motive for this is that the knowledge generated can serve as a basis of information and references which aid in decision-making for public authorities who need to start similar programs or improve existing ones. The Action-Research occurred in a Brazilian city with less than 100,000 inhabitants, which fits the profile of 94.91% of the country’s municipalities. Final results proved the efficiency of the action-research proposal; after implementing the changes, the monthly collections grew by 50% (action), and the Action-Research team was able to generate and document knowledge which can now help other cities to improve their own processes.  相似文献   
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This article is a slightly summarized version of an invited plenary at the Aegean Seminar, which took place at the Greek island of Samos in July 1992. The original title was “An Interpretive Systemological View of the Issue: ‘Environmental Fluctuations and Cultural Change in Island Societies.”’ It is an hermeneutical inquiry into the interpretive context that provides full meaning to the issue of Environmental Fluctuations and Cultural Change. The roots of the relationship of causality embedded in such a title are traced so that its underlying ontological assumptions are uncovered. This sort of archaeological inquiry will finally unearth the interpretive context that provides full meaning to such a relationship of causality, namely,neoevolutionary organicism. This theoretical outcome of Modernity embraces natural and social sciences under the aegis of a single way of thinking, feeling, and acting which buries the Enlightenment conception of liberty and its consequent problem of morality and of practical reason.  相似文献   
30.
Summary In a wild population ofDrosophila melanogaster located near Madrid (Spain), it has been found that the frequency of morphological mutant phenotypes is 0.36 per captured female. The study of these females shows that they carry 3.6 recessive mutants in heterozygous condition per female. The genetic variability found is higher than the frequencies observed by other authors in other natural populations.I thank Dr F.J. Ayala for useful discussions and help in preparing the English text.  相似文献   
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