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81.
Platelet-Rich Plasma (PRP) is enriched in molecular messengers with restorative effects on altered tissue environments. Upon activation, platelets release a plethora of growth factors and cytokines, either in free form or encapsulated in exosomes, which have been proven to promote tissue repair and regeneration. Translational research on the potential of exosomes as a safe nanosystem for therapeutic cargo delivery requires standardizing exosome isolation methods along with their molecular and morphological characterization. With this aim, we isolated and characterized the exosomes released by human PRP platelets. Western blot analysis revealed that CaCl2-activated platelets (PLT-Exos-Ca2+) released more exosomes than non-activated ones (PLT-Exos). Moreover, PLT-Exos-Ca2+ exhibited a molecular signature that meets the most up-to-date biochemical criteria for platelet-derived exosomes and possessed morphological features typical of exosomes as assessed by transmission electron microscopy. Array analysis of 105 analytes including growth factors and cytokines showed that PLT-Exos-Ca2+ exhibited lower levels of most analytes compared to PLT-Exos, but relatively higher levels of those consistently validated as components of the protein cargo of platelet exosomes. In summary, the present study provides new insights into the molecular composition of human platelet-derived exosomes and validates a method for isolating highly pure platelet exosomes as a basis for future preclinical studies in regenerative medicine and drug delivery.  相似文献   
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A significant proportion of power generation stems from coal-combustion processes and accordingly represents one of the largest point sources of CO2 emissions worldwide. Coal power plants are major assets with large infrastructure and engineering units and an operating life span of up to 50 years. Hence, any process design modification to reduce greenhouse gas emissions may require significant investment. One of the best options to utilize existing infrastructure is to retrofit the power station fleet by adding a separation process to the flue gas, a practice known as postcombustion capture (PCC). This review examines the recent PCC development and provides a summary and assessment of the state of play in this area and its potential applicability to the power generation industry. The major players including the various institutes, government, and industry consortia are identified along with flue gas PCC demonstration scale plants. Of the PCC technologies reviewed, amine-based absorption is preeminent, being both the most mature and able to be adapted immediately, to the appropriate scale, for power station flue gas with minimal technical risk. Indeed, current commercial applications serve niches in the merchant CO2 market, while a substantial number of smaller scale test facilities are reported in the literature with actual CO2 capture motivated demonstrations now commencing. Hybrid membrane/absorption systems, also known as membrane contactors, offer the potential for the lowest energy requirements, possibly 10% of current direct scrubbers but are at an early stage of development. Other methods being actively pursued as R&;D projects include solid absorbents, solid adsorbents, gas membrane separators, and cryogenic separation. The variety and different maturities of these competing technologies make technical comparison largely subjective, but useful insights could be gained through the development and application of econometric techniques such as ‘real options’ within this context. Despite these limitations, it is clear from this review that amine scrubbing is likely to be adapted first into the existing power station fleet, while less mature technologies will grow and become integrated with the development of future power stations.  相似文献   
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The availability of machine-readable bilingual linguistic resources is crucial not only for rule-based machine translation but also for other applications such as cross-lingual information retrieval. However, the building of such resources (bilingual single-word and multi-word correspondences, translation rules) demands extensive manual work, and, as a consequence, bilingual resources are usually more difficult to find than “shallow” monolingual resources such as morphological dictionaries or part-of-speech taggers, especially when they involve a less-resourced language. This paper describes a methodology to build automatically both bilingual dictionaries and shallow-transfer rules by extracting knowledge from word-aligned parallel corpora processed with shallow monolingual resources (morphological analysers, and part-of-speech taggers). We present experiments for Brazilian Portuguese–Spanish and Brazilian Portuguese–English parallel texts. The results show that the proposed methodology can enable the rapid creation of valuable computational resources (bilingual dictionaries and shallow-transfer rules) for machine translation and other natural language processing tasks).  相似文献   
84.
Platelet-rich plasma (PRP) is a biologic therapy that promotes healing responses across multiple medical fields, including the central nervous system (CNS). The efficacy of this therapy depends on several factors such as the donor’s health status and age. This work aims to prove the effect of PRP on cellular models of the CNS, considering the differences between PRP from young and elderly donors. Two different PRP pools were prepared from donors 65–85 and 20–25 years old. The cellular and molecular composition of both PRPs were analyzed. Subsequently, the cellular response was evaluated in CNS in vitro models, studying proliferation, neurogenesis, synaptogenesis, and inflammation. While no differences in the cellular composition of PRPs were found, the molecular composition of the Young PRP showed lower levels of inflammatory molecules such as CCL-11, as well as the presence of other factors not found in Aged PRP (GDF-11). Although both PRPs had effects in terms of reducing neural progenitor cell apoptosis, stabilizing neuronal synapses, and decreasing inflammation in the microglia, the effect of the Young PRP was more pronounced. In conclusion, the molecular composition of the PRP, conditioned by the age of the donors, affects the magnitude of the biological response.  相似文献   
85.
In this work we propose a generalization of the notion of directional monotonicity. Instead of considering increasingness or decreasingness along rays, we allow more general paths defined by curves in the n-dimensional space. These considerations lead us to the notion of α-monotonicity, where α is the corresponding curve. We study several theoretical properties of α-monotonicity and relate it to other notions of monotonicity, such as weak monotonicity and directional monotonicity.  相似文献   
86.
Related variety and regional growth in Spain*   总被引:9,自引:0,他引:9  
This paper investigates whether related variety, among other types of spatial externalities, affected regional growth in Spain at the NUTS 3 level during the period 1995–2007. We found evidence that related variety matters for growth across regions, especially when using two new methods that measure revealed relatedness between industries. The first method is based on Porter's cluster classification while the second method uses the proximity index proposed by Hidalgo et al. Our analyses show that Spanish provinces with a wide range of related industries tend to show higher economic growth rates, once we control for other determinants of growth. Este artículo investiga si la variedad relacionada, entre otros tipos de externalidades espaciales, afectó el crecimiento regional en España a nivel NUTS 3 durante el periodo 1995‐2007. Hallamos pruebas de que la variedad relacionada influye en el crecimiento entre regiones, especialmente al utilizar dos métodos nuevos que miden el grado de conexión manifiesto entre industrias. El primer método está basado en la clasificación de conglomerados de Porter, mientras que el segundo método utiliza el índice de proximidad propuesto por Hidalgo et al. Nuestros análisis muestran que las provincias españolas con un amplio rango de industrias relacionadas tienden a mostrar tasas de crecimiento económico más altas, una vez que se logra controlar otros factores determinantes del crecimiento.   相似文献   
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The Internet is a huge interconnection of thousands of networks with different technologies, equipment, configurations, and administrative owners. This, added to the lack of public information about those individual infrastructures, makes it a difficult task to provide a so-called Internet map: a topological map with information of routers, interconnections between routers, and IP addressing configuration. Traditional topology discovery methods based on traceroutes only provide IP addresses in the path between end-nodes. Some of those IP addresses can belong to the same router, and this identification is made by alias resolution methods. Therefore, alias resolution allows to provide router-level map of the Internet with important applications in network simulation, protocol design, network management, network security, network service design, and geolocation. In this paper, alias resolution methods are analyzed in Internet core networks (GlobalNOC, Canet4, and Geant). This allows to identify peculiar behaviors in these core networks, improving alias resolution methods. Simultaneously, reduction methods are used to decrease the number of probing packets in alias resolution methods.  相似文献   
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