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排序方式: 共有466条查询结果,搜索用时 15 毫秒
1.
Extracellular vesicles (EVs) are a heterogeneous group of cell-derived submicron vesicles released under physiological or pathological conditions. EVs mediate the cellular crosstalk, thus contributing to defining the tumor microenvironment, including in epithelial ovarian cancer (EOC). The available literature investigating the role of EVs in EOC has been reviewed following PRISMA guidelines, focusing on the role of EVs in early disease diagnosis, metastatic spread, and the development of chemoresistance in EOC. Data were identified from searches of Medline, Current Contents, PubMed, and from references in relevant articles from 2010 to 1 April 2020. The research yielded 194 results. Of these, a total of 36 papers, 9 reviews, and 27 original types of research were retained and analyzed. The literature findings demonstrate that a panel of EV-derived circulating miRNAs may be useful for early diagnosis of EOC. Furthermore, it appears clear that EVs are involved in mediating two crucial processes for metastatic and chemoresistance development: the epithelial–mesenchymal transition, and tumor escape from the immune system response. Further studies, more focused on in vivo evidence, are urgently needed to clarify the role of EV assessment in the clinical management of EOC patients.  相似文献   
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Four hundred forty-six patients with Tourette Syndrome (TS) and/or their parents completed a 52-item self-report survey about vocal and motor tics, and the frequency of associated co-morbid conditions of aggression, obsessions and compulsions, attentional problems, sleep disturbance, mood disturbance, anxiety, and self-mutilative behaviours which have been frequently reported in the literature on TS. Respondents also responded to an open-ended question regarding the most disabling aspects of TS. Results were analyzed within two age groups; under 18 years of age (N = 245) and 18 years of age or older (N = 177). Tics and associated conditions were the most frequently reported disabling aspect by both age groups. Subjects under age 18, however, reported significantly more frequent problems with hyperactivity, temper control, aggressive behaviours and sleepwalking than adults with TS.  相似文献   
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Baker and confectioner apprentices have been included in a prospective follow-up study in the region of East Thuringia, to evaluate risk factors for the development of hand dermatitis. Starting in August 1996, the apprentices have been interviewed and examined in a standardized way right at the beginning (n=91) of their vocational training, 6 (n=79) and 12 months (n=63) later. To gain objective data, TEWL score was also assessed at 3 standardized sites on the hands. In their case histories, 3.3% (n=3) of the apprentices reported hand dermatitis. The 1st assessment after 2 to 4 weeks vocational training revealed hand eczema in 17.5% (n=16) of the individuals. At the follow-up after 6 months of training 29.1% (n=23), and after 12 month of training 27.0% (n=17), of the apprentices had hand dermatitis of mild to moderate severity. Within 6 months, the TEWL score rose significantly (p<0.001) from 11.9 g m(-2) h(-1) (-/+5.4) to 16.8 g m(-2) h(-1) (-/+9.5). After 12 months, the TEWL score was 14.9 g m(-2) h(-1) (-/+4.6). For the atopic skin diathesis (>10 points of Diepgen's atopy score), there was a significant tendency to be a predictive factor for the development of occupational hand dermatitis. TEWL score failed to correlate with the development of skin damage in our study. The same was true for respiratory atopy and metal sensitization.  相似文献   
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Two Canadian rapeseed oils, “Westar” and “low-linolenic”, supplied by the Canola Council were studied and compared with a French rapeseed. The linolenic acid content of the low-linolenic variety is about 3%. This drop in the C18∶3 is completely compensated for by an increase in the C18∶2. Seventy-two percent of the triglycerides with at least one linolenic chain disappeared. A strong increase in the OOL and OLL was observed. The room-odor tests showed that the “low-linolenic” had a significantly higher odor score than the French rapeseed and the “Westar”, both of these being very similar. A fruity odor dominated in the “low-linolenic”, and the fishy painty odors were particularly reduced.  相似文献   
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We introduce a new, online, stroke-based recognition system for hand-drawn diagrams which belong to a group of documents with an explicit structure obvious to humans but only loosely defined from the machine point of view. We propose a model for recognition by selection of symbol candidates, based on evaluation of relations between candidates using a set of predicates. It is suitable for simpler structures where the relations are explicitly given by symbols, arrows in the case of diagrams. Knowledge of a specific diagram domain is used—the two domains are flowcharts and finite automata. Although the individual pipeline steps are tailored for these, the system can readily be adapted for other domains. Our entire diagram recognition pipeline is outlined. Its core parts are text/non-text separation, symbol segmentation, their classification and structural analysis. Individual parts have been published by the authors previously and so are described briefly and referenced. Thorough evaluation on benchmark databases shows the accuracy of the system reaches the state of the art and is ready for practical use. The paper brings several contributions: (a) the entire system and its state-of-the-art performance; (b) the methodology exploring document structure when it is loosely defined; (c) the thorough experimental evaluation; (d) the new annotated database for online sketched flowcharts and finite automata diagrams.  相似文献   
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Shen L  Sheng Y  Prémont G 《Applied optics》1995,34(20):4004-4012
The circular harmonic filter contains only one component of the image. Its discrimination capability has been questionable. The geometrical approach of multiple circular harmonic filters uses relative locations of the correlation peaks as the rotation-, shift-, and intensity-invariant features for pattern recognition. Each feature depends on the entire image. This approach has a good discrimination capability. Optical real-time implementation of the on-axis continuous phase-only circular harmonic filters by the use of a commercial liquid-crystal television is shown. A harmonic analysis shows that the phase-mostly filter can tolerate coupled amplitude modulation at the acceptable expense of the output signal-to-noise ratio. An optical experiment of the geometrical approach of multiple circular harmonic filters for a multiple-image input is described. The cross-correlation peaks between the individual filters and the clutter are eliminated, because they are not in good locations.  相似文献   
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A model of cortical neurons capable of sustaining a low level of spontaneous activity is investigated. Without learning the activity of the network is chaotic. We report on attempts to learn synfire chains in this type of network by introducing a Hebbian learning mechanism and exciting a small set of neurons at random intervals. We discuss the types of instabilities that can arise and prevent the formation of long synfire chains and also discuss various biologically plausible mechanisms which to some extent cure these instabilities.  相似文献   
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