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91.
One of the needs of the Pelagos Sanctuary for the Conservation of Mediterranean Marine Mammals is information on critical habitats for cetaceans. This study modelled habitat use and preferences of fin whales and striped dolphins (the two most abundant species in the area) with the aim of providing this information, using sighting data collected between 1993 and 1999. The study area was divided into a 2′ latitude by 2′ longitude grid. The explanatory variables considered in the models were physiographic variables (mean, range and standard deviation of depth and slope, and distance from the nearest coastline) and remotely-sensed data (Sea Surface Temperature and Chlorophyll-a concentration). The former were calculated for each cell using GIS tools, while the latter were obtained from AVHRR and SeaWiFS sensors. Generalized Additive Models (GAMs) with multidimensional smoothers were used to model the distribution of fin whales and striped dolphins in relation to these variables, and Classification And Regression Trees were used for habitat characterization and predictive models. The GAMs were coupled with Generalized Estimating Equations (GEEs) to account for temporal autocorrelation in the errors and to help ensure model selection was reliable; the QIC statistic was used alongside GEE-based p-values. Bathymetric features were the most valuable predictors in the Pelagos Sanctuary area for both species. Sea Surface Temperature values were indicators of striped dolphin and fin whale presence, with both species showing a tendency to prefer colder waters (21–24 °C). Chl-a levels were selected by the GAM models only for striped dolphins, and with large associated uncertainty; this may be related to the relatively brief period examined (only 2 years) and/or to any functional relationship operating at a different geographical or temporal scale. The boosted classification trees however indicated an importance of Chl-a for both species. The techniques applied to this dataset proved to be valuable tools to describe habitat use and preferences of cetaceans, and the use of the remotely-sensed data can substantially improve the predictions. The results of this study will be used for assessing critical habitats within the Pelagos Sanctuary and will provide information for conservation and management in the Sanctuary.  相似文献   
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93.
Timed tree automata with an application to temporal logic   总被引:1,自引:0,他引:1  
Finite automata on -sequences and -trees were introduced in the sixties by Büchi, McNaughton and Rabin. Finite automata on timed -sequences were introduced by Alur and Dill. In this paper we extend the theory of timed -sequences to -trees. The main motivation is the introduction of a new way to specify real-time systems and to study, using automata-theoretic techniques, branching-time temporal logics with timing constraints. We study closure properties and decision problems for the obtained classes of timed -tree languages. In particular, we show the decidability of the emptiness problem. As an application of the introduced theory, we give a new decidable branching time temporal logic (STCTL) whose semantics is based upon timed -trees. Received: 8 September 1997 / 27 June 2001  相似文献   
94.
Gastro-entero-pancreatic neuroendocrine neoplasms (GEP-NENs) are rare diseases occurring in the gastrointestinal tract and pancreas. They are characterized by the loss of epithelial tubular gland elements, and by the increased expression of neuroendocrine markers. GEP-NENs are subdivided into two histo-pathological types, gastro-entero-pancreatic neuroendocrine tumors (GEP-NETs) and gastro-entero-pancreatic neuroendocrine carcinomas (GEP-NECs). According to WHO 2017 and 2019 classification criteria are graded and staged in four categories, NET-G1, NET-G2, NET-G3, and NEC-G3. The molecular characterization of these tumors can be fundamental for the identification of new diagnostic, prognostic and predictive biomarkers. The main purpose of this study was to analyze the expression of the paralogous 13 HOX genes, normally involved in embryogenic development and frequently deregulated in human cancers, and of the HOX regulating lncRNA HOTAIR in GEP-NENs. The expression of HOX genes is gradually lost in the transition from GEP NET G1 to NET/NEC G3 tumors, while HOTAIR expression, inversely correlated with HOX genes expression and weakly expressed in low-grade GEP NENs, becomes aberrant in NET G3 and NEC G3 categories. Our data highlights their potential role in the molecular stratification of GEP-NENs by suggesting new prognostic markers and potential therapeutic targets.  相似文献   
95.
The ‘shock-and-kill’ strategy to purge the latent HIV reservoir relies on latency-reversing agents (LRAs) to reactivate the provirus and subsequent immune-mediated killing of HIV-expressing cells. Yet, clinical trials employing histone deacetylase inhibitors (HDACis; Vorinostat, Romidepsin, Panobinostat) as LRAs failed to reduce the HIV reservoir size, stressing the need for more effective latency reversal strategies, such as 2-LRA combinations, and enhancement of the immune responses. Interestingly, several LRAs are employed to treat cancer because they up-modulate ligands for the NKG2D NK-cell activating receptor on tumor cells. Therefore, using in vitro T cell models of HIV latency and NK cells, we investigated the capacity of HDACis, either alone or combined with a distinct LRA, to potentiate the NKG2D/NKG2D ligands axis. While Bortezomib proteasome inhibitor was toxic for both T and NK cells, the GS-9620 TLR-7 agonist antagonized HIV reactivation and NKG2D ligand expression by HDACis. Conversely, co-administration of the Prostratin PKC agonist attenuated HDACi toxicity and, when combined with Romidepsin, stimulated HIV reactivation and further up-modulated NKG2D ligands on HIV+ T cells and NKG2D on NK cells, ultimately boosting NKG2D-mediated viral suppression by NK cells. These findings disclose limitations of LRA candidates and provide evidence that NK cell suppression of reactivated HIV may be modulated by specific 2-LRA combinations.  相似文献   
96.
In order to study the composition of the lactic acid bacteria (LAB) community of sourdoughs used for the manufacture of Altamura bread, a traditional durum wheat bread produced in Apulia (Southern Italy), 111 strains of LAB were isolated and characterized. The phenotypic characterization of the isolates, carried out using a set of 29 tests, allowed the identification of 15 clusters at the 80% similarity level by hierarchical cluster analysis. Of the isolates, 88% were identified as facultatively heterofermentative LAB (Lactobacillus plantarum, Lb. paracasei, Lb. casei) and 12% as heterofermentative LAB (Lb. brevis, Leuconostoc mesenteroides). SDS-PAGE profiles of whole cell proteins of 68 strains confirmed the identification. Both the diversity and structure of the lactic microflora for sourdoughs for Altamura bread varied among samples.  相似文献   
97.
Notwithstanding the existence of a broad research base on assembly line balancing (ALB), companies do not use the mathematical approaches developed in the literature to configure assembly lines. This article aims to fill the gap between research and application by presenting and testing in a real industrial context a methodology based on complexity reduction and kaizen events. First, the methodology supports reducing the complexity that affects real-life assembly systems in terms of the variety of, e.g. finished products, materials and parts. Next, the methodology proposes the conduction of kaizen events by using lean manufacturing tools, such as process analysis, time observation, waste identification, workstation standard documents and yamazumi charts. The methodology is successfully applied to a case study that describes its use in the confectionery process for a major chocolatier company along with the results of the application. The main contribution of this paper consists in presenting a method to manage the line balancing activity within everyday industrial realities, helping practitioners to improve and maintain the performance over time.  相似文献   
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99.
The antioxidant properties of nine different samples of freshly drawn, pasteurised and UHT milk were examined before and after fermentation with several lactobacilli, individually and in combination with the yeast Saccharomyces boulardii. The results showed no statistical differences for the content in proteins, fats and carbohydrates of the different milk. The antioxidant properties of the unfermented milk were positively affected by the thermal treatment. All samples of fermented milk had a greater antioxidant activity than unfermented but only for the freshly drawn milk that increase was significantly different. The co‐incubation of lactobacilli with the yeast determined a stronger antioxidant activity especially for the freshly drawn milk. The stability of the tested strains during storage in standard conditions was determined in UHT fermented milk to enable a possible use in probiotic food production. The results showed that the yeast incubated with lactobacilli determined an improvement of the viability of bacteria.  相似文献   
100.
The aim of this work was to study the influence of hen age and housing system on egg performances in fresh pasta production, focusing on mechanical and rheological properties of pasta. Samples of pasta were prepared with eggs laid by Hy‐Line Brown hens (from 27 to 68 weeks old) housed in conventional cage, barn and organic systems. Only hen age significantly affected pasta properties. In particular, as regards raw pasta, the loosest structure was obtained using eggs laid by the youngest hens (27–30 weeks old). On the contrary, in cooked pasta, the weakest structure was observed when eggs were laid by hens aged 53–68 weeks. However, differences, although significant, were small and thus most likely not sensorially perceivable. Significant correlations were found between mechanical and rheological properties of raw fresh egg pasta, meaning that small deformation measurements are as valuable as large deformation tests for the characterisation of this product.  相似文献   
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