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1.
The in vitro activity of Bay 12-8039, a new oral 8-methoxyquinolone, was compared to the activities of 11 other oral antimicrobial agents (ciprofloxacin, levofloxacin, ofloxacin, sparfloxacin, azithromycin, clarithromycin, amoxicillin clavulanate, penicillin, cefuroxime, cefpodoxime, and doxycycline) against 250 aerobic and 140 anaerobic bacteria recently isolated from animal and human bite wound infections. Bay 12-8039 was active against all aerobic isolates, both gram-positive and gram-negative isolates, at < or = 1.0 microg/ml (MICs at which 90% of isolates are inhibited [MIC90s < or = 0.25 microg/ml) and was active against most anaerobes at < or = 0.5 microg/ml; the exceptions were Fusobacterium nucleatum and other Fusobacterium species (MIC90s, > or = 4.0 microg/ml) and one strain of Prevotella loeschii (MICs, 2.0 microg/ml). In comparison, the other quinolones tested had similar in vitro activities against the aerobic strains but were less active against the anaerobes, including peptostreptococci, Porphyromonas species, and Prevotella species. The fusobacteria were relatively resistant to all the antimicrobial agents tested except penicillin G (one penicillinase-producing strain of F. nucleatum was found) and amoxicillin clavulanate.  相似文献   
2.
By affecting the activity of the adaptation motor, Ca2+ entering a hair bundle through mechanoelectrical transduction channels regulates the sensitivity of the bundle to stimulation. For adaptation to set the position of mechanosensitivity of the bundle accurately, the free Ca2+ concentration in stereocilia must be tightly controlled. To define the roles of Ca2+-regulatory mechanisms and thus the factors influencing adaptation motor activity, we used confocal microscopy to detect Ca2+ entry into and clearance from individual stereocilia of hair cells dialyzed with the Ca2+ indicator fluo-3. We also developed a model of stereociliary Ca2+ homeostasis that incorporates four regulatory mechanisms: Ca2+ clearance from the bundle by free diffusion in one dimension, Ca2+ extrusion by pumps, Ca2+ binding to fixed stereociliary buffers, and Ca2+ binding to mobile buffers. To test the success of the model, we compared the predicted profiles of fluo-3 fluorescence during the response to mechanical stimulation with the fluorescence patterns measured in individual stereocilia. The results indicate that all four of the Ca2+ regulatory mechanisms must be included in the model to account for the observed rate of clearance of the ion from the hair bundle. The best fit of the model suggests that a free Ca2+ concentration of a few micromolar is attained near the adaptation motor after transduction-channel opening. The free Ca2+ concentration substantially rises only in the upper portion of the stereocilium and quickly falls toward the resting level as adaptation proceeds.  相似文献   
3.
As a method for counseling children, play therapy continues to demonstrate effectiveness through research and to be included in mental health training programs throughout the country. However, like other counseling interventions, capturing the essence of the therapeutic environment is complex and dependent on individual perspectives and experiences. In this article, two case studies are presented to demonstrate the use of quantitative and qualitative measures in comparing the behavioral changes as rated by caregivers on the Child Behavior Checklist (CBCL) and play themes observed by play therapists over a 6-week period. For both children in the study, behaviors and themes were related. As the children made changes in their play themes over the 6-week period, they also made changes in their behaviors at home. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
4.
1H NMR spectra of the duodenum, jejunum and ileum tissues of the small intestine of a rat showed metabolic gradients. 2. The concentrations of metabolites in these gut regions were altered by the presence of the tapeworm Hymenolepis diminuta. 3. In the infected duodenum there was significantly less glycogen, glucose and phosphocreatine/creatine, but significantly more lactate than in the corresponding controls. 4. Infected jejunum contained significantly less betaine but significantly more succinate, alanine and lactate. 5. Infected ileum had significantly less glycogen and taurine but significantly more alanine and lactate.  相似文献   
5.
We present data for 4 He adsorption to thermally evaporated C 60 films for 1.30 K < T < 2.17 K. This work minimizes possible effects due to the presence of adsorbed species other than 4 He. We observe an anomalous mass adsorption to the C 60 films close to 4 He saturation which amounts to 3 times the expected mass loading due to the saturated 4 He film on the C 60 surface at T = 1.30K.  相似文献   
6.
A sorbent injection test program was carried out at NRG Texas Power LLC's (NRG) Limestone Electric Generating Station (LMS). LMS fires a 30/70 blend of Powder River Basin (PRB) and Texas Lignite, and is equipped with a cold-side electrostatic precipitator (ESP) and wet scrubber. The plant markets its fly ash for beneficial use, so development of a low ash impact mercury control technology is important to the economics of implementing a mercury control system. In addition to standard activated carbon injection, two different low ash impact mercury control technologies were evaluated in parametric tests: low ash impact sorbents and Toxecon™ II. The parametric ACI test program conducted at LMS demonstrated that high (>90%) levels of mercury removal could be achieved with carbon sorbents. The Toxecon™ II design used at LMS did not provide for as high a mercury removal as injection upstream of the ESP, likely due to poor coverage of the cross-sectional area of the ESP. Limited concrete testing was performed with simulated ash/carbon mixtures. As expected, the amount of air-entraining additive required increased with increasing carbon content in the ash. However, it appeared that small amounts of non-passivated carbon may be acceptable in fly ash for concrete use.  相似文献   
7.
The effect of systemic administration of the selective neurotoxin N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine (DSP-4) on noradrenaline efflux in the frontal cortex was studied in freely-moving rats using microdialysis in vivo. Five days after treatment with DSP-4 (40 mg/kg i.p.), the noradrenaline content of the frontal cortex was reduced by 75%. Yet, noradrenaline efflux in the frontal cortex was nearly two-fold greater in DSP-4 treated rats than in saline-injected controls. Local infusion of the noradrenaline-selective uptake blocker, desipramine (5 microM), via the microdialysis probe, increased noradrenaline efflux in rats from both groups. Perfusion of Ringer's solution, containing 80 mM K+, also increased noradrenaline efflux in both groups, but the increase after DSP-4 pretreatment was greater than in the controls. In contrast, removal of Ca2+ from the infusion medium reduced noradrenaline efflux in both treatment groups. These results indicate that, at this dose, DSP-4 increases the extracellular concentration of noradrenaline in rat frontal cortex despite causing a partial lesion of noradrenergic neurones. This is due to an increase in the release of noradrenaline, although reduced clearance is also likely. These data challenge the assumption that depletion of noradrenaline content after treatment with DSP-4 invariably translates into diminished noradrenergic transmission.  相似文献   
8.
High-speed X-ray phase contrast imaging synchronized with a Kolsky bar apparatus was utilized to investigate the cracking behavior of a borosilicate glass, a soda lime glass, and a glass ceramic in front of a cylindrical projectile with an impact velocity of 5 ms−1. For each material, three different surface conditions were prepared for the impacted edge of the specimen. Angular cracking was observed in front of the projectile for borosilicate glass. For soda lime glass, straight cracking was observed. For glass ceramic, curved cracking was observed in front of the projectile. Cracking behavior was observed to be independent of the surface condition on the impacted edge.  相似文献   
9.
Fracture behaviors of single, two, and multiple contacting spherical Poly(methyl methacrylate) (PMMA) particles were recorded using high speed synchrotron X-ray phase contrast imaging. A miniaturized Kolsky bar setup was used to apply dynamic compressive loading on the PMMA particles. In both single and two particle experiments, cracking initiated near the center of the particles and propagated towards the contacts. The crack bifurcated near the contact points for single particle experiments, thus forming conical fragments. The crack bifurcation and subsequent conical fragment formation was observed only at the particle-particle contact for two particle experiments. The particles were observed to fracture in hemispherical fragments normal to the contact plane in the multi-particle experiments. The observed failure mechanisms strongly suggest that the maximum tensile stress near the center of the particle is the critical parameter governing fracture of the particles. Furthermore, the compressive stress under the contact areas led to the bifurcation and subsequent conical fragment formation.  相似文献   
10.
We report the case of an 82-year-old man with a 12-month history of recurrent hemoptysis caused by an aortobronchial fistula. Twenty-five years earlier, the patient underwent placement of an aortic graft for aortic transection sustained in a motor vehicle accident. Chest radiography and bronchoscopy showed nonspecific abnormalities. We emphasize the role of CT angiography with 2D and 3D reconstructions for the diagnosis of and surgical planning for this rare but potentially lethal aortic postoperative complication.  相似文献   
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