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Gray scale B-scans in renal sinus lipomatosis show a variety of features which must be differentiated from clinically significant pathological processes. Normal kidneys show dense homogeneous central echoes. In renal sinus lipomatosis, however, the central echoes are divided and become more sparse (Type I), interspersed with small relatively echo-free areas (Type II), or outline a single relatively echo-free area resembling a mass (Type III). In contrast to similar features in hydronephrosis or multiple cysts, the relatively echo-free areas in lipomatosis are ill-defined and do present several weak internal echoes. 相似文献
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Anthony P. Raphael Tarl W. Prow Michael L. Crichton Xianfeng Chen Germain J. P. Fernando Mark A. F. Kendall 《Small (Weinheim an der Bergstrasse, Germany)》2010,6(16):1785-1793
Targeting of vaccines to abundant immune cell populations within our outer thin skin layers using miniaturized devices—much thinner than a needle and syringe, could improve the efficacy of vaccines (and other immunotherapies). To meet this goal, a densely packed dissolving microprojection array (dissolving Nanopatch) is designed, achieving functional miniaturization by 1) formulating small microneedles (two orders of magnitude smaller than a standard needle and syringe) and 2) multiple layering of the payload within microprojections with tight tolerances (of the order of a micrometer). The formulation method is suitable to many vaccines because it is without harsh or complex chemical processes, and it is performed at low temperatures and at a neutral pH. When the formulated dNPs are applied to skin, consistent and robust penetration is achieved, rapidly targeting the skin strata of interest (<5 min; significantly faster than larger dissolving microneedles that have been previously reported). Resultant diffusion is significantly enhanced within the dermis compared with the epidermis. Using two different antigens (ovalbumin and a commercial trivalent influenza vaccine [Fluvax2008]), the administration of these dissolving patches generate robust systemic immune responses in a mouse model. To the authors' knowledge, this is the first report of successful vaccination with any form of dissolving microneedles. The patches made by this method therefore have the potential for pain‐free, needle‐free, and effective vaccination in humans. 相似文献
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Recent clinical studies of pulmonary arterial hypertension (PAH) have found correlations between increased pulmonary vascular stiffness (PVS) and poorer disease outcomes. However, mechanistic questions remain about the relationships amongst PVS, RV power, and vascular hemodynamics in the setting of progressive PAH that are difficult or impossible to answer using direct measurements. Clinically validated patient-specific computational modeling may allow exploration of these issues through perturbation-based predictive testing. Here we use a simple patient-specific model to answer four questions: how do hemodynamics change as PAH worsens? How does increasing PVS impact hemodynamics and RV power? For a patient with moderate PAH, what are the consequences if the pressures increase modestly yet sufficiently to engage collagen in those vessels? What impact does pressure-reducing vasodilator treatment have on hemodynamics? Twenty-one sets of model-predicted impedance and mean PA pressure (mPAP) show good agreement with clinical measurements, thereby validating the model. Worsening was modeled using data from three PAH outcomes groups; these show not only the expected increase in mPAP, but also an increase in pressure pulsatility. Interestingly, chronically increasing mPAP decreased WSS, suggesting that increased PA cross-sectional area affected WSS greater than increased PVS. For a patient with moderately high PVR (12.7 WU) with elastin-based upstream vascular remodeling, moving from elastin-dominant vessel behavior to collagen-dominant behavior caused substantial increases in mPAP, pressure and WSS pulsatility. For the same patient, reducing PVR through a simulated vasodilator to a value equivalent to mild PAH did not decrease pressure pulsatility and dramatically increased WSS pulsatility. Overall, these results suggest a close association between PVS and hemodynamics and that hemodynamics may play an important role in progressing PAH. These support the hypothesis that treatments should target decreasing or reversing upstream vascular remodeling in addition to decreasing mean pressures. 相似文献
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Normative comparisons are a procedure for evaluating the clinical significance of therapeutic interventions. Although a step-by-step statistical methodology for conducting normative comparisons has been reported elsewhere (P. C. Kendall, A. Marrs-Garcia, S. R. Nath, & R. C. Sheldrick, 1999), questions regarding the collecting of normative data remain. For this study, all treatment outcome studies published in the Journal of Consulting and Clinical Psychology from 1988 to 1997 were examined and reviewed, and the 5 most commonly used outcome measures were identified. For these outcome measures, multiple sources of normative data were located. Although we identified a dearth of normative data on measures used for treatment outcome, results discussed here nevertheless provide information that may be of use to therapy outcome evaluators when conducting normative comparisons. In addition, equations to determine the minimum sample size needed in a normative sample for a given treatment outcome study are provided. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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The role and implementation of evidence-based practice and empirically supported treatments has been hotly contested among researchers and practitioners. Using examples of and from various empirically supported treatments the authors offer suggestions for smoothing the pathway for dissemination of evidence-based practice with children and adolescents. The authors underscore that mediational analyses, treatment process studies, and the continued creation of flexible treatment manuals are important components of successful dissemination. Flexibility within fidelity is proposed as the preferred perspective that eases the transition and dissemination of empirically supported treatments from research clinics to service clinics. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Extensive studies are underway in the UK and elsewhere to investigate the consequences of a hypothetical core disruptive accident in a fast reactor. Within these studies there is a continuing need to determine the response of the primary containment system to loads generated by such a major release of energy. A number of fast reactor containment codes are currently being developed for this purpose.The COVA (COva VAlidation) program of experiments is being undertaken to provide high quality data against which the codes can be validated. The tests progress from simple bare vessel assemblies to tests incorporating the main axisymmetric features of loop and pool reactor designs.A companion paper in this journal discusses recent developments in the containment code SEURBNUK which is being jointly developed by the UKAEA and JRC Ispra. This paper describes the status of the validation of SEURBNUK against data from the COVA experiments. Considerable progress has been made in the application of the code to the more complex configurations of the later tests which are more representative of reactor geometries and it is concluded that SEURBNUK has reached a stage where it provides a useful calculational capability for containment analysis. Nevertheless, further work is needed to improve the predictions of vessel deformations and roof loadings in some geometries. 相似文献