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Two hundred and fifteen children aged 4 months 6 years with acute otitis media (AOM) were randomized to be treated either by a single i.m. injection of ceftriaxone, 50 mg/kg, with a second dose in the event of unsatisfactory response after 48 h or a history of recurrent AOM (109 patients) or amoxicillin clavulanate 12.5 mg tid (106 patients). The failure rate was similar in children treated by ceftriaxone and amoxicillin clavulanate, 4.6% and 4.7%, respectively (standard error for intergroup difference -2.87%, 95% confidence interval -5.62% to 5.87%). No significant differences between the groups were found in the dynamics of the resolution of the acute symptomatology, otoscopy findings, relapse rate at 30 days or tympanographic evidence of middle ear effusion at the scheduled visits on days 30, 60 and 90. Recurrence of AOM between days 31 and 90 was observed significantly in more children treated with amoxicillin clavulanate than with ceftriaxone--25 out of 84 (29.4%) versus 11 out of 81 (13.6%) (P = 0.012). Conclusion: Ceftriaxone injection(s) is as efficient at least as 10-day oral amoxicillin clavulanate for treatment of acute otitis media in children. Although not recommended as routine, ceftriaxone can be considered in the management of acute otitis media under special circumstances, particularly in cases when the ability to tolerate or absorb oral drugs is compromised, in children refusing or unable to take oral therapy or when the compliance is questionable.  相似文献   
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Summary We propose hot-potato (or, deflection) packet routing algorithms on the two-dimensional mesh. The algorithms are strongly greedy in the sense that they attempt to send packets in good directions whenever possible. Furthermore, the routing operations are simple and independent of the time that has elapsed. The first algorithm gives the best evacuation time known for delivering all the packets to their destinations. A batch ofk packets with maximal source-to-destination distanced max is delivered in 2(k-1)+d max. The second algorithm improves this bound tok+d max when all packets are destined to the same node. This also implies a new bound for the multitarget case, which is the first to take into account the number of in-edges of a node. The third algorithm is designed for routing permutations with source-to-destination distance at most three, in which case the algorithm terminates in at most seven steps. We also show a lower bound of five steps for this problem. Ishai Ben-Aroya received the B.A. and M.Sc. in computer science from the Technion (Israel Institute of Technology). He is currently working with Microsoft Israel R&D group. His main interests include Routing Algorithms, Cryptography and Computer Security. Tamar Eilam received the B.A. degree in Computer Science from the Technion IIL in 1995, and is currently studying towards her M.A. degree. Assaf Schuster received his B.A., M.A. and Ph.D. degrees in Computer Science from the Hebrew University of Jerusalem (the last one in 1991). He is currently a lecturer at the Technion IIL. His main interests include Networks and Routing Algorithms, Parallel and Distributed Computation, Optical Computation and Communication, Dynamically Reconfiguring Networks, and Greedy Hot Potato Routing.This work was supported in part by the French-Israeli grant for cooperation in Computer Science, and by a grant from the Israeli Ministry of Science. An extended abstract appeared in proc. 2nd European Symposium on Algorithms, September 1994  相似文献   
4.
In this paper, a computer vision based interactive multi-touch tabletop system called HumanTop is introduced. HumanTop implements a stereo camera vision subsystem which allows not only an accurate fingertip tracking algorithm but also a precise touch-over-the-working surface detection method. Based on a pair of visible spectra cameras, a novel synchronization circuit makes the camera caption and the image projection independent from each other, providing the minimum basis for the development of computer vision analysis based on visible spectrum cameras without any interference coming from the projector. The assembly of both cameras and the synchronization circuit is not only capable of performing an ad-hoc version of a depth camera, but it also introduces the recognition and tracking of textured planar objects, even when contents are projected over them. On the other hand HumanTop supports the tracking of sheets of paper and ID-code markers. This set of features makes the HumanTop a comprehensive, intuitive and versatile augmented tabletop that provides multitouch interaction with projective augmented reality on any flat surface. As an example to exploit all the capabilities of HumanTop, an educational application has been developed using an augmented book as a launcher to different didactic contents. A pilot study in which 28 fifth graders participated is presented. Results about efficiency, usability/satisfaction and motivation are provided. These results suggest that HumanTop is an interesting platform for the development of educational contents.  相似文献   
5.
Selective Laser Melting (SLM) was used to process a powder mixture of CP Ti, 6.5 wt% Mo and 3.5 wt% Mo2C. The process parameters were optimized to obtain full-density, crack free parts. After the in situ decomposition of Mo2C in favor of the formation of TiC, the material consisted of a homogeneous dispersion of submicrometer sized TiC platelets in a β-(Ti,Mo) matrix exhibiting a high hardness up to 550 HV and compressive yield stress of 1164 ± 37 MPa. The microstructure and mechanical properties could be tailored by variation of the process parameters within the high-density processing window, as well as through post-process heat treatments.  相似文献   
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Input–output analysis is a powerful tool for in-depth study of the productive structure of economic space. Moreover, the sectoral network constitutes one of the possible determinants of the innovative capacity of a territory. The use of network theory in the input–output field supposes an interesting alternative that allows structural complexity, weakness and strength to be shown. Following this viewpoint, we analyse the relative position of each sector via the structural holes concept (Burt in Structural Holes, Cambridge University Press, Cambridge, 1992; Social Capital: Theory and Research. Aldine de Gruyter, New York, 2001; Am J Sociol 110:349–399, 2004) to offer an approach to knowledge generation and diffusion capacity within the economic network. The theoretical background is based on the opportunities afforded due to connexion with and proximity to sectoral structure for knowledge transmission and consequently innovation capacity. This novel proposal is applied to the analysis of European and Spanish economies in 1995.  相似文献   
8.
To select for bacterial strains with enhanced phenotypes, random fragments of a whole genome, or a defined region of the genome, are cloned in a nonreplicating vector. The resulting plasmids are integrated by recombination into the homologous DNA region of the original strain. Integration gives rise to a nontandem direct duplication of the corresponding DNA region separated by the vector moiety of the plasmid. Recombination between the direct repeats leads to tandem duplication and further amplification of the entire integrated DNA, including the vector. Bacteria harboring the amplified DNA are selected by increasing the dosage of an antibiotic corresponding to a resistance marker of the integrated vector. Pooled strains carrying amplifications are then challenged with a selective pressure for the desired phenotype. After repeated selection cycles, the most fit strains are isolated. We used this process, which we called random DNA amplification, to select Rhizobium strains with increased competitiveness for nodule formation. Derivatives containing randomly amplified DNA regions of the symbiotic plasmid of Rhizobium tropici CFN299 strain were generated. Pools of amplified strains were inoculated onto various tropical legumes. After several cycles of selection through plants, amplified derivatives showing an increased competitiveness for nodule formation with the leguminous plant Macroptilium atropurpureum were obtained.  相似文献   
9.
Rats treated chronically with the dopamine agonist quinpirole (0.5 mg/kg, twice weekly x 10) met 5 criteria for performance of compulsive checking. Specifically, in a large open-field with single small objects in 4 of 25 locales, quinpirole rats revisited two places/objects excessively often and rapidly, compared with other locations in the environment or saline controls. They performed a ritual-like set of behavioral acts at these two places/objects and stopped in relatively few locales before returning to the preferred places/objects. Finally, they shifted their behavior to a new location when the object was moved there. Clomipramine (10 mg/kg, daily) postponed but did not prevent the development of the quinpirole effect. Quinpirole-induced compulsive checking may be an exaggeration of normal checking of home site in rats. Results suggest an animal model of obsessive-compulsive disorder and a role for dopamine in this disorder.  相似文献   
10.
Exposure of cardiac myocytes from adult rat ventricles to the highly selective, high affinity sigma receptor ligands 1S,2 R-cis-N-[2-(3,4-dichlorophenyl)ethyl]-N-methyl-2-(1-pyrrolidinyl)-cycloh exylamine (BD-737) (0.1-100 nM) and N-[2-(3,4-dichlorophenyl)ethyl]-N,N',N'-trimethylethylenediamine (BD-1047) (0.01-10 nM), caused potentiation of electrically-evoked amplitudes of contraction and Ca2+ transients, while exposure to 100 nM BD-1047 caused attenuation of these amplitudes. In addition, BD-737 (1-100 nM) and BD-1047 (10-100 nM) caused an increase in the incidence of spontaneous twitches. These effects were inhibited when the incubation with BD-737 was done in the presence of the phospholipase C inhibitor, neomycin, or after pre-incubation with thapsigargin or caffeine which deplete the sarcoplasmic reticulum Ca2+ stores. Inositol 1,4,5-trisphosphate (IP3) production in cardiac myocytes was determined by the IP3 binding protein assay. Both substances caused an increase in the intracellular concentration of IP3. BD-737 caused a rapid transient increase to 3.2-fold in 1 min and stabilization at 2.1-fold of control thereafter. BD-1047 caused a gradual increase reaching 4.4-fold after 5 min. The results suggest that the effects of these sigma receptor ligands on contractility and spontaneous contractions are mediated by activation of phospholipase C and elevation of intracellular IP3 level.  相似文献   
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