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1.
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   
2.
The authors suggest that procedural and distributive factors interactively combine to influence individuals' reactions to their encounters with other people, groups, and organizations. Results from 45 independent samples (reviewed herein) show that (1) level of procedural justice is more positively related to individuals' reactions when outcome fairness or valence is relatively low and (2) level of outcome fairness or valence is more positively related to individuals' reactions when procedural justice is relatively low. They present various explanations of the interaction effect. Theoretical progress may be achieved through future efforts to delineate the conditions under which each of the explanations is more versus less likely to account for the interaction. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
3.
Modified atmosphere packaging (MAP) is commonly used to preserve the quality of ready-to-eat lettuce by inhibiting oxidative browning and growth of microbial populations. The efficacy of MAP is improved by the initial displacement of air with a gas mixture of a desirable composition (active MAP). The present work focused on the effects of MAP on indigenous microbial populations and the survival of Salmonella enterica on the surface of the lettuce. Chlorine-washed leaves of romaine lettuce were inoculated with S. enterica serotype Typhimurium or not inoculated and packaged in one of the three systems: (a) passive MAP in polyethylene bags; (b) active MAP in the same bags with a gas mixture of 10% O2, 10% CO2, and 80% N2; and (c) control without MAP. Active MAP ensured the more rapid establishment of a steady-state atmosphere and favorable conditions during the transitional period preceding the steady state. The active MAP had an antimicrobial effect on indigenous lettuce microflora, but not on Salmonella and even favored the survival of the pathogen, possibly due to the elimination of its natural antagonists. The effects of the passive MAP were less pronounced. The results obtained draw attention to potential safety risks of ready-to-eat fresh produce kept in active MAP and require further investigation.  相似文献   
4.
A polychromatic k-coloring of a plane graph G is an assignment of k colors to the vertices of G such that each face of G, except possibly for the outer face, has all k colors on its boundary. A rectangular partition is a partition of a rectangle R into a set of non-overlapping rectangles such that no four rectangles meet at a point. It was conjectured in [Y. Dinitz, M.J. Katz, R. Krakovski, Guarding rectangular partitions, in: 23rd European Workshop Computational Geometry, 2007, pp. 30-33] that every rectangular partition admits a polychromatic 4-coloring. In this note we prove the conjecture for guillotine subdivisions — a well-studied subfamily of rectangular partitions.  相似文献   
5.
Two different approaches, blending and layer-by-layer electrostatic deposition (LbL), were utilized to combine two biopolymers, gelatin and chitosan, in edible films or coatings. The performance of the blended and LbL composite films and single-component gelatin and chitosan films was compared in terms of mechanical, optical, and spectroscopic properties. In parallel, edible coatings based on these formulations were applied on a food model: fresh-cut melon. Physiological, textural, and microbiological parameters of the coated fruit were studied in comparison with non coated control. Surprisingly, in spite of the higher thickness, the composite films and especially the LbL formulation demonstrated enhanced water vapor permeability as compared to single-component films. The LbL film had higher strength and better elasticity than the blended one. All edible coatings containing chitosan effectively inhibited microbial growth on fresh-cut melons. The LbL formulation demonstrated the most effective inhibition of the total microbial growth especially after 5–7 days of storage, while the blended formulation demonstrated high antifungal activity after 11 days of storage. The LbL formulation demonstrated superior performance in preservation of fruit texture and also slightly reduced fruit weight loss, while the blended formulation did not improve these parameters. Both composite coatings do not obstruct fruit gas exchange and do not cause accumulation of off-flavor volatiles.  相似文献   
6.
A field survey and laboratory experiment examined the determinants of survivors' reactions to job layoffs. Independent variables included (1) change in the perceived intrinsic quality of the content of survivors' jobs relative to before the layoffs and (2) context favorability, as determined by (a) the perceived fairness of the layoffs and (b) survivors' perceptions of their co-workers' reactions to the layoffs. Both studies revealed similiar Job Content?×?Context interaction effects on the primary dependent variable of commitment: Change in job content was more strongly (positively) related to survivors' organizational and task commitment when the context was more favorable. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
7.
It has been posited that high self-esteem persons (high SEs) are more confident than low self-esteem persons (low SEs) of their capability to provide meaningful input in a decision process. If this is so, then high SEs should be more influenced by their perceived level of voice, relative to low SEs. Survey data from 4 field studies showed that voice was more positively related to various dependent variables among high SEs than low SEs. In Study 5, the authors experimentally manipulated voice as well as participants' beliefs about their capability to provide meaningful input. As expected, voice had a greater impact on the reactions of participants who were led to believe that they were more capable of providing meaningful input. Theoretical implications are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
8.
Potato juice proteins were fractionated by acidification to pH 3 into acid-coagulable and acid-soluble fractions. Both fractions are heterogeneous. They differ in molecular weight, conformation in solution and composition of amino acids. The acid-coagulable fraction consists of units of molecular weight between 32,000 and 87,000, while the acid-soluble fraction consists of units of molecular weight between 17,000 and 27,000. Circular dichroism measurements show that the acid-coagulable fraction is in helical and beta conformations whilst, for the acid-soluble fraction, a substantial contribution of the random conformation is observed. The acid-coagulable fraction has a higher content of methionine than the acid-soluble fraction. It is shown that this type of fractionation is more meaningful than fractionation in terms of albumins and globulins by solubility in water or dilute salt solutions.  相似文献   
9.
This study examined how leader relational behaviors (i.e., relational leadership) cultivate bonding social capital among organizational members and the way bonding social capital augments feelings of vigor at work. In addition, the authors examined how vigor enhances employee job performance. Using a sample of 209 participants in Israeli community centers, the results of structural equation modeling indicate a 2-stage mediation model in which leader relational behaviors are positively related to bonding social capital; this, in turn, results in feelings of vigor, which are positively associated with manager ratings of employee job performance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
10.
Multifunctional flexible sensors that are sensitive to different physical and chemical stimuli but remain unaffected by any mechanical deformation and/or changes still present a challenge in the implementation of flexible devices in real‐world conditions. This challenge is greatly intensified by the need for an eco‐friendly fabrication technique suitable for mass production. A new eco‐friendly and scalable fabrication approach is reported for obtaining thin and transparent multifunctional sensors with regulated electrical conductivity and tunable band‐gap. A thin (≈190 nm thickness) freestanding sensing film with up to 4 inch diameter is demonstrated. Integration of the freestanding films with different substrates, such as polyethylene terephthalate substrates, silk textile, commercial polyethylene thin film, and human skin, is also described. These multifunctional sensors can detect and distinguish between different stimuli, including pressure, temperature, and volatile organic compounds. All the sensing properties explored are stable under different bending/strain states.  相似文献   
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