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1.
Mood disorders afflict pediatric patients, cause significant impairment, and interfere with normal development. Increasingly, pediatricians are called on to assess and collaborate with mental health practitioners in medicating children and adolescents with mood disorders. Approaching the juvenile with a primary emphasis on clarifying the diagnoses, determining environmental antecedents and sequelae, and investigating suicide risk enables the pediatrician to institute appropriate treatment. Despite limited data from controlled studies, psychotherapy often is used for mild to moderate depression. Pharmacotherapy is indicated in cases unresponsive to psychotherapy and in severe or suicidal cases. First-line pharmacotherapy for depressed adolescents is usually an SRI followed by the atypical or TCA antidepressants. Bipolar disorder typically requires an aggressive medication regimen, including anticonvulsants, lithium, or a combination, as well as environmental modifications. With severe, difficult, or refractory cases, mental health consultation is recommended to clarify diagnoses and to provide psychotherapy and medication input.  相似文献   
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Multipath propagation in a broadband CDMA environment is described. A propagation model for broadband spread-spectrum signals is presented. Experimental results relating to the sharing of the band by fixed service microwave users and mobile personal communications network (PCN) users are discussed. Field tests indicate that PCN systems can provide high-quality communications when sharing the spectrum with fixed-service microwave systems in suburban and urban areas  相似文献   
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Most drugs induce conditioned taste aversions and are therefore commonly supposed to produce nausea and sickness. Paradoxically, some drugs appear to lose induction capability when made to serve as a cue for a 2nd drug that produces more severe sickness, perhaps through selective association with a hypothetical homeostatic or antisickness aftereffect of sickness. Using drug–drug pairings has made antisickness conditioning theory difficult to validate. Rotation serves in lieu of a drug cue in rats. Rotation–drug pairings eliminate drug interactions and enable the sorts of parametric manipulations required to validate the theory. By postulating a common sickness mechanism to explain both taste aversion and aversion failure, the theory places the phenomenon within an adaptive evolutionary framework. Successful application could yield a direct countermeasure to severe nausea in clinical settings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Although the exact path of acquisition remains incompletely understood, research supports the association between anxiety disorders in children and psychopathologic conditions in adults. This article addresses this relationship; reviews findings on the temperamental profile and behavioral inhibition, which may be an early identifiable childhood predictor of later anxiety disorders; and discusses the importance of early intervention.  相似文献   
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Thermal barrier coatings (TBCs), consisting of physical vapor deposited (PVD) partially stabilized zirconia (PSZ, 8 wt.%Y2O3) and a diffusion aluminide bond coat, were characterized as a function of time after oxidative isothermal heat treatment at 1373 K in air. The experimental characterizations was conducted by X-ray diffraction analysis and scanning electron microscopy (SEM) with energy-dispersive spectroscopy. During cooling to room temperature, spallation of the PSZ ceramic coatings occurred after 200 and 350 h of isothermal heat treatment. This failure was always sudden and violent, with the TBC popping from the substrate. The monoclinic phase of zirconia was first observed on the bottom surface of the PVD PSZ after 200 h of isothermal heat treatment. The failure of TBCs occurred either in the bond coat oxidation products of αAl2O3 and rutile TiO2 or at the interface between the oxidation products and the diffusion aluminide bond coat or the PSZ coating.  相似文献   
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Plasma polymer nanostructures were prepared by cluster beam deposition. The nanocluster source assembled in our laboratory is implementing a 2 in. planar magnetron operated in radio-frequency mode and follows the Haberland concept. Clusters were deposited on glass or silicon substrates without mass separation in order to get high deposition rates. C:H plasma polymer clusters with a typical size of about 100 nm (measured by AFM) were prepared by RF discharge in argon/hexane atmosphere. The influence of deposition conditions was studied with respect to size distribution (AFM and SEM), chemical and physical properties (XPS and FTIR) of resultant clusters.  相似文献   
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Objective: To examine the efficacy of a developmentally appropriate parent–child cognitive behavioral therapy (CBT) protocol for anxiety disorders in children ages 4–7 years. Method: Design: Randomized wait-list controlled trial. Conduct: Sixty-four children (53% female, mean age 5.4 years, 80% European American) with anxiety disorders were randomized to a parent–child CBT intervention (n = 34) or a 6-month wait-list condition (n = 30). Children were assessed by interviewers blind to treatment assignment, using structured diagnostic interviews with parents, laboratory assessments of behavioral inhibition, and parent questionnaires. Analysis: Chi-square analyses of outcome rates and linear and ordinal regression of repeated measures, examining time by intervention interactions. Results: The response rate (much or very much improved on the Clinical Global Impression Scale for Anxiety) among 57 completers was 69% versus 32% (CBT vs. controls), p  相似文献   
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Cellulose acetate membranes (CA) were modified by means of plasma polymerization of ethylene diamine (EDA) and n‐butylamine (n‐BA). The motivation for this work was the application of a modified membrane for the single‐layer enzyme electrode. A tubular reactor with the external radiofrequency (13.56 MHz) excitation was used. Surface modification was performed at 5, 10, and 15 W power (at 27 Pa working pressure) for 5, 10, 15 min. Modified surfaces were characterized in detail by FTIR–ATR, XPS (ESCA), contact angle, and enzyme immobilization activity. The best treatment results were obtained for EDA with 5 W and 30 min and 15 W and 10 min. These results are discussed using surface analysis data. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 1341–1352, 2001  相似文献   
10.
Titania (TiO2) nanofibers and composite thin films of titania nanofibers and Safranin O dye (SAF) were studied. TiO2 nanofibers were prepared by electrospinning technique from titanium tetra-isopropoxide precursor solution in ethanol. Surface topology of the nanofibers was observed using scanning electron microscopy (SEM), their crystal structure was studied by X-ray diffraction (XRD) and the chemical composition by X-ray photoelectron spectroscopy (XPS). Properties of the TiO2 nanofibers were studied in dependence on the values of relative air humidity in the range from 15% to 55%. It was necessary to maintain the relative humidity lower than 30% during electrospinning in order to obtain high quality nanofiber films. The average minimum diameter of the as-prepared TiO2 nanofibers was found to be around 100 nm. Nanofiber diameter diminishes to about 50 nm after annealing at 420 °C for 1 h. The as-prepared titania nanofiber films were completely amorphous while anatase crystal phase was detected in the films after annealing. In order to prepare the composite films, solution of SAF dye with poly(vinylpyrrolidone) in ethanol/water was dropped off on the prepared titania nanofibers surface. Opto-electrical properties of SAF dye and the resulting nanocomposite films were studied by UV–Vis spectroscopy and current–voltage characteristics. Safranin O is characterized by two strong absorption peaks; one at 274 nm and a wide band with splitting between 420 nm and 600 nm. The optical energy band gap of titania nanofibers was estimated from the UV–Vis measurements to be 3.4 eV. The charge transport in the composite films is influenced by the space charge limited currents due to the very high resistance of the materials.  相似文献   
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