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The internal anal sphincterotomy operation represents the best therapy for the treatment of those anal lesions, above all anal fissures, which cause hypertrophy and spasms of the internal anal sphincter. The Authors report their experience of 253 operations of internal subcutaneous sphincterotomy carried out between 1989 and 1995 under local anaesthesia in the outpatient clinic. The excellent results achieved prove that the procedure can easily be carried out under local anaesthesia in an outpatient clinic and, therefore, it is preferable to the surgical technique of isolation of the internal sphincter, not only for its practicality but also for the improved results. 相似文献
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A novel directive and nondispersive antenna is presented: the ultrawideband (UWB) leaky lens. It is based on the broad band Cherenkov radiation occurring at a slot printed between different infinite homogeneous dielectrics. The first part of the paper presents the antenna concept and the UWB design. The issues that are specifically addressed include the impedance matching, the radiation pattern and the phase purity. Subsequently the hardware demonstrator and the results of the measurement campaign are shown. The results fully validate the antenna concept. The antenna presents decade bandwidth impedance matching, directive and frequency independent patterns in the H-plane over two octaves, negligible cross-polarization levels, weak amplitude dispersivity and, according to the authors, the most stable phase center for a directive antenna over an ultra wide frequency range. 相似文献
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Absorption and distribution of polyunsaturated fatty acids was investigated in rats receiving lysophospholipids per os (30 mg kg-1). Lysophosphatidylcholine (lysoPC) increased [3H]arachidonate absorption and its incorporation into mucosal phosphatidylcholine. Transport of [3H]arachidonate by the phospholipid fraction of lymph lipoproteins and the level of [3H]arachidonate in plasma and liver lipids was also increased by lyso PC. Lysophosphatidylserine also increased [3H]arachidonate absorption but channeled the fatty acids into the aminophospholipid fraction of mucosal phospholipids, thus decreasing its efflux in lymph lipoproteins. As a consequence, lysophosphatidylserine caused [3H]arachidonate accumulation in mucosa. As similar results were obtained with [14C]linoleate, the data suggest that the addition of an appropriate lysophospholipid to the diet may direct absorption and distribution of polyunsaturated fatty acids. 相似文献
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Angela S. Rocha Arnaldo C. Faro Jr. Laetitia Oliviero Jacob Van Gestel Franoise Maug 《Journal of Catalysis》2007,252(2):321-334
The activity of NiMoS catalysts supported on niobia, alumina, and niobia/alumina was compared for the thiophene hydrodesulfurization (HDS) and 2,6-dimethylaniline (2,6-DMA) hydrodenitrogenation (HDN) reactions. To evaluate the acidity of the supports and identify the nature of the sulfide sites, adsorption of 2,6-dimethylpyridine, pyridine, and CO was performed and followed by IR spectroscopy. This study has shown that with niobia as a support, the activity of NiMoS catalysts in thiophene HDS and in HDN of 2,6-DMA was no longer promoted by the synergy between Ni and Mo. The absence of synergy between molybdenum and nickel on niobia can be explained by the strong interaction of each metal with niobia at the expense of interaction with each other. Moreover, it has been shown that on a niobia/alumina support, the formation of the NiMoS phase can be directly linked to the presence of alumina not covered by niobia. However, niobia is an interesting support for the HDN of 2,6-DMA, because it favors the formation of xylene through direct ammonia elimination involving low H2 consumption. The activity for xylene formation on niobia is linked to the electron-deficient nature of the Mo sulfide site, as demonstrated by CO adsorption followed by IR. 相似文献
7.
Lorenzo Gatti Marco Guerini Oliviero Stock Carlo Strapparava 《Computational Intelligence》2015,31(4):669-683
The need for creativity is ubiquitous, and mobile devices connected to Web services can help us. Linguistic creativity is widely used in advertisements to surprise us, to get our attention, and to stick concepts in our memory. However, creativity can also be used as a defense. When we walk in the street, we are overwhelmed by messages that try to get our attention with any persuasive device at hand. As messages get ever more aggressive, often our basic cognitive defenses—trying not to perceive those messages—are not sufficient. One advanced defensive technique is based on transforming the perceived message into something different (for instance, making use of irony or hyperbole) from what was originally meant in the message. In this article, we describe an implemented application for smartphones, which creatively modifies the linguistic expression in a virtual copy of a poster encountered on the street. The mobile system is inspired by the subvertising practice of countercultural art. 相似文献
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Maria Elena Bruni Francesca Guerriero 《International Transactions in Operational Research》2010,17(2):207-220
The aim of this paper is to investigate the use of heuristic information to efficiently solve to optimality the robust shortest path problem. Starting from the exact algorithm proposed by Murty and Her, we describe how this algorithm can be enhanced by using heuristic rules and evaluation functions to guide the search. The efficiency of the proposed enhanced approach is tested over a range of random generated instances. Our computational results indicate that the use of heuristic criteria is able to speed up considerably the search and that the enhanced exact solution method outperforms the state‐of‐the‐art algorithm proposed by Murty and Her in most of the instances. 相似文献
9.
Vittoria Bruni Andrew Crawford Anil Kokaram Domenico Vitulano 《Signal, Image and Video Processing》2013,7(1):11-26
This paper presents a novel model for the removal of semi-transparent blotches on the digitized copy of sepia archive photographs. As these defects cannot be successfully eliminated by conventional interpolation methods, a proper combination of a novel visual distortion and multiresolution analysis is used for performing user-independent detection and restoration. Extensive experimental results and comparative studies show the potential of the proposed model in terms of visual quality and computational complexity. 相似文献
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