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81.
ERUM NADEEM S. SERENE OLIN LAURA CAMPBELL HILL KIMBERLY EATON HOAGWOOD SARAH McCUE HORWITZ 《The Milbank quarterly》2013,91(2):354-394
Context
In response to national efforts to improve quality of care, policymakers and health care leaders have increasingly turned to quality improvement collaboratives (QICs) as an efficient approach to improving provider practices and patient outcomes through the dissemination of evidence-based practices. This article presents findings from a systematic review of the literature on QICs, focusing on the identification of common components of QICs in health care and exploring, when possible, relations between QIC components and outcomes at the patient or provider level.Methods
A systematic search of five major health care databases generated 294 unique articles, twenty-four of which met our criteria for inclusion in our final analysis. These articles pertained to either randomized controlled trials or quasi-experimental studies with comparison groups, and they reported the findings from twenty different studies of QICs in health care. We coded the articles to identify the components reported for each collaborative.Findings
We found fourteen crosscutting components as common ingredients in health care QICs (e.g., in-person learning sessions, phone meetings, data reporting, leadership involvement, and training in QI methods). The collaboratives reported included, on average, six to seven of these components. The most common were in-person learning sessions, plan-do-study-act (PDSA) cycles, multidisciplinary QI teams, and data collection for QI. The outcomes data from these studies indicate the greatest impact of QICs at the provider level; patient-level findings were less robust.Conclusions
Reporting on specific components of the collaborative was imprecise across articles, rendering it impossible to identify active QIC ingredients linked to improved care. Although QICs appear to have some promise in improving the process of care, there is great need for further controlled research examining the core components of these collaboratives related to patient- and provider-level outcomes. 相似文献82.
MARC R. SCHMID MANUEL MURBACH CAROLINE LUSTENBERGER MICHELINE MAIRE NIELS KUSTER SARAH P. LOUGHRAN 《Journal of sleep research》2012,21(6):620-629
Studies have repeatedly shown that electroencephalographic power during sleep is enhanced in the spindle frequency range following radio frequency electromagnetic field exposures pulse‐modulated with fundamental frequency components of 2, 8, 14 or 217 Hz and combinations of these. However, signals used in previous studies also had significant harmonic components above 20 Hz. The current study aimed: (i) to determine if modulation components above 20 Hz, in combination with radio frequency, are necessary to alter the electroencephalogram; and (ii) to test the demodulation hypothesis, if the same effects occur after magnetic field exposure with the same pulse sequence used in the pulse‐modulated radio frequency exposure. In a randomized double‐blind crossover design, 25 young healthy men were exposed at weekly intervals to three different conditions for 30 min before sleep. Cognitive tasks were also performed during exposure. The conditions were a 2‐Hz pulse‐modulated radio frequency field, a 2‐Hz pulsed magnetic field, and sham. Radio frequency exposure increased electroencephalogram power in the spindle frequency range. Furthermore, delta and theta activity (non‐rapid eye movement sleep), and alpha and delta activity (rapid eye movement sleep) were affected following both exposure conditions. No effect on sleep architecture and no clear impact of exposure on cognition was observed. These results demonstrate that both pulse‐modulated radio frequency and pulsed magnetic fields affect brain physiology, and the presence of significant frequency components above 20 Hz are not fundamental for these effects to occur. Because responses were not identical for all exposures, the study does not support the hypothesis that effects of radio frequency exposure are based on demodulation of the signal only. 相似文献
83.
SARAH TRAULLÉ M.D. SHINSUKE MIYAZAKI M.D. VINCENT MOUQUET M.D. MACIEJ KUBALA M.D. JEAN‐SYLVAIN HERMIDA M.D. 《Pacing and clinical electrophysiology : PACE》2012,35(12):1420-1427
Background : Although pulmonary vein (PV) stenosis is a serious complication of radiofrequency PV isolation, the anatomical impact of a combination of two energy sources on PV diameter has not been evaluated. The aim of this study was to evaluate the impact of supplementary point‐by‐point radiofrequency applications (following PV cryoablation) on the PV orifice diameter. Methods : Forty‐nine patients having undergone PV isolation for drug‐refractory atrial fibrillation were included. All had undergone cardiac computed tomography before ablation and again at least 3 months afterwards. When isolation with the cryoballoon was not complete, a conventional irrigated‐tip radiofrequency catheter was used for point‐by‐point applications. Results : Of the 189 target PVs, 117 were isolated with cryotherapy alone (cryo PVs) and 72 required additional radiofrequency (hybrid PVs). The second scan (performed an average of 11.4 ± 5.4 months after) showed a decrease in diameter for all the hybrid PVs (17.2 ± 2.6 to 16.3 ± 3.4 mm; P = 0.037) but no change for the cryo PVs. This change was associated with a decrease in left superior pulmonary vein (LSPV) diameter (19.2 ± 3.0 to 17.8 ± 4.9 mm, P = 0.014). There were no changes in other veins. A subgroup analysis for the LSPV revealed a decrease for the hybrid PVs (18.8 ± 3.6 to 15.9 ± 7.1 mm, P = 0.046) but not for the cryo PVs. Significant PV stenosis was observed in three hybrid PVs (two severe stenosis of the LSPV and one moderate stenosis of the right inferior pulmonary vein) but not in cryo PVs (4.1% vs 0%, respectively; P = 0.023). Conclusions : Cryoballoon ablation of the PV with adjunct, focal, irrigated ostial RF applications may be associated with a higher risk of PV stenosis. (PACE 2012;35:1420–1427) 相似文献
84.
Splenomegaly in infants and children often presents an interesdng
problem for differential diagnosis. As a cause of the sign, a variety of
entirely unrelated conditions may be mentioned. Among the common
groups of such conditions are acute and chronic infections, parasitic
diseases, blood disorders, mechanical pressure on the venous flow,
tumors and certain diseases of unkown nature. While one shouId con-
sider as rrany causes of splenic enlargement as possible in the handling
of an unusual case, a knowledge of the incidence of the common diseasos
or conditions with which splenomegaly is often associated in infancy
and childhood would be of distinct help in the daily pediatric practice. 相似文献
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88.
ARTHUR M. FELIX EDGAR P. HEIMER CHING-TSO WANG THEODORE J. LAMBROS ALAIN FOURNIER THOMAS F. MOWLES SARAH MAINES ROBERT M. CAMPBELL BOGDA B. WEGRZYNSKI VOLDEMAR TOOME DAVID FRY VINCENT S. MADISON 《Chemical biology & drug design》1988,32(6):441-454
A novel cyclic GRF analog, cyclo(Asp8-Lys12)-[Asp8,Ala15]-GRF(1-29)-NH2, i.e. cyclo8.12[Asp8,Ala15]-GRF(1-29)-NH2, was synthesized by the solid phase procedure and found to retain significant biological activity. Solid phase cyclization of Asp8 to Lys12 proceeded rapidly (~2h) using the BOP reagent. Substitution of Ala12 with d -Ala2 and/or NH2-terminal replacement (desNH2-Tyr1 or N-MeTyr1) in the cyclo8.12[Asp8,Ala15]-GRF(1-29)-NH2 system resulted in highly potent analogs that were also active in vivo. Conformational analysis (circular dichroism and molecular dynamics calculations based on NOE-derived distance constraints) demonstrated that cyclo8.12[Asp8,Ala15]-GRF(1-29)-NH2 contains a long α-helical segment even in aqueous solution. A series of cyclo8.12 stereoisomers containing d -Asp8 and/or d -Lys12 were prepared and also found to be highly potent and to retain significant α-helical conformation. The high biological activity of cyclo8.12[N-MeTyr1,d -Ala2,Asp8,Ala15]-GRF(1-29)-NH2 may be explained on the basis of retention of a preferred bioactive conformation. 相似文献
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