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61.
62.
PURPOSE: To compare the quality of care in teaching hospitals with that in nonteaching hospitals. METHOD: By performing a literature review via PubMed, the author identified and surveyed 23 studies that compared the quality of care in teaching hospitals with that in nonteaching hospitals. The studies were published from 1989-2004 and in all but one case dealt exclusively with U.S. hospitals. RESULTS: The teaching hospitals studied had better-quality measures than did nonteaching hospitals in the predominant number of studies reviewed. Process measures were significantly better in teaching hospitals in seven of the eight studies where such measures were observed, and equal in the other study. Risk-adjusted mortality was lower in teaching hospitals in nine of the 15 studies using that measure, not significantly different in five, and significantly lower in nonteaching hospitals in one study (in pediatric intensive care units, even though the teaching hospitals had a better process of care). In nonmortality outcomes, teaching hospitals were better in one study using that measure; there were no significant differences in five other such studies. Major teaching hospitals had more favorable outcomes end points than did minor teaching hospitals in eight studies in which they were compared. Including only those six studies using clinical data for process analysis or risk adjustment, teaching hospitals had a better process in all six and lower adjusted mortality in five of seven studies where that measure was used. CONCLUSIONS: Overall, the favorable results in teaching hospitals extended over a range of locations, conditions, and populations, including routine as well as complex conditions. However, the quality measured in these studies was not at target levels across the spectrum of hospitals. There needs to be a continuous and determined effort for improvement in all institutions. It is to be hoped that teaching hospitals will take the lead not only in continuously improving their own quality, but also in developing and evaluating ever improving methods of quality assessment.  相似文献   
63.
We report the case of a woman with refractory celiac disease who developed abnormal spontaneous movements of the extremities and face consistent with myorhythmia. Investigation led to a diagnosis of encephalitis, confirmed by postmortem examination. The movements were likely caused by nonparaneoplastic encephalitis associated with refractory celiac disease. Etiologic and diagnostic considerations and treatment options are discussed.  相似文献   
64.
Braun Jr  Martin  MD  Cook Joel  MD 《Dermatologic surgery》2005,31(S2):995-1005
Background. Surgical defects following the extirpation of cutaneous neoplasia may present challenges to the dermatologic surgeon. There are many repair options for an individual defect, including second-intention healing, primary closure, skin graft, and skin flap closure. The island pedicle flap is a random pattern advancement flap well suited to reconstruct a variety of small- to intermediate-sized soft tissue wounds.
Objective. To review the utility of the island pedicle flap in reconstructive dermatologic surgery and to detail the operative technique to achieve reproducible functional and esthetic results.
Methods. The method of flap reconstruction is presented. A variety of defects repaired with this technique are reviewed.
Results. The subcutaneous island pedicle flap yielded excellent functional and cosmetic repair of the presented defects with minimal operative morbidity. Secondary to a well-preserved central vascular pedicle, complications are infrequent.
Conclusions. The random pattern island pedicle flap is a versatile and robust flap used to repair a variety of soft tissue wounds in a single-stage procedure with reproducible operative outcomes.  相似文献   
65.
Increasing systolic blood pressure and heart rate during the early morning results in increased myocardial oxygen demand. The use of β blockers during this period may decrease cardiac workload, particularly in β-blocker sensitive patients. The impact of a new chronotherapeutic β blocker was assessed in 44 hypertensive patients. Patients were randomized to delayed-release propranolol (INP) dosed at 10 p.m. or to traditionally dosed propranolol (ILA) dosed at 8 a.m. for 4 weeks, following which they were switched to the alternative formulation for 4 weeks. Thirty-four-hour ambulatory blood pressure monitoring and pharmacokinetic measurements were obtained. INP and ILA resulted in significant reductions in mean 24-hour blood pressure (−9.01-6.9 mm Hg and −10.41-7.7 mm Hg, respectively). The top 25% of responders to highdose propranolol (sensitive patients) were compared on each formulation. Mean trough reductions were −8.0/-6.7 mm Hg and −7.61-5.8 mm Hg, respectively. Mean blood pressure reductions in the β-blocker sensitive patients (n=11) between 6 a.m. and noon were −15.2/-11.9 mm Hg on INP and -8.0/-4.6 mm Hg on ILA. Heart rate reduction was −14.1 bpm and double product reduction was −3319 in the INP patients between 6 a.m. and 12 noon compared with −10.5 and −2209 in the ILA patients. This study suggests that INP and ILA are effective once-a-day β blockers, but the use of delayed-release propanolol results in a greater reduction in double product between 6 a.m. and noon in β-blocker sensitive patients than does traditionally dosed propranolol.  相似文献   
66.
The goal of this study is to develop unique native endothelium mimicking nanomatrices and evaluate their effects on adhesion and spreading of human umbilical vein endothelial cells (HUVECs) and aortic smooth muscle cells (AoSMCs). These nanomatrices were developed by self-assembly of peptide amphiphiles (PAs) through a solvent evaporation technique. Three PAs, one containing the Tyr-Ile-Gly-Ser-Arg (YIGSR) ligand, the second containing the Val-Ala-Pro-Gly (VAPG) ligand, and a third without cell adhesive ligands, were developed. Cell adhesion and spreading were evaluated by a PicoGreen-DNA assay and live/dead assay, respectively. Our results show that PA-YIGSR significantly enhances HUVEC adhesion (26,704 ± 2708), spreading (84 ± 8%), and proliferation (50 ± 2%) compared with that of other PAs. PA-VAPG and PA-YIGSR showed significantly greater AoSMC adhesion compared with that of PA-S. PA-VAPG also showed significantly greater spreading of AoSMCs (63 ± 11%) compared with that of other PAs. Also, all the PAs showed significantly reduced platelet adhesion compared with that of collagen I (control). These findings would facilitate the development of novel vascular grafts, heart valves, and cell-based therapies for cardiovascular diseases.From the Clinical EditorThe goal of this study was to develop unique native endothelium mimicking nanomatrices and evaluate their effects on adhesion and spreading of human umbilical vein endothelial cells (HUVECs) and aortic smooth muscle cells (AoSMCs). These nanomatrices were developed by self-assembly of peptide amphiphiles through a solvent evaporation technique. The findings are expected to facilitate the development of novel vascular grafts, heart valves, and cell based therapies for cardiovascular diseases.  相似文献   
67.
68.
Low-frequency stimulation is associated with long-term depression (LTD) of synaptic efficacy in various brain structures. Like long-term potentiation (LTP), homosynaptic LTD in area CA1 of the hippocampus appears to require NMDA receptor activation, changes in postsynaptic calcium concentration and phospholipase A2 (PLA2) activation. Arachidonic acid (AA) is released after the activation of calcium-dependent phospholipases and free AA is rapidly metabolized to a family of bioactive products (the eicosanoids) which are thought to be both intracellular and extracellular messengers. In the present study, we investigated the involvement of the cyclooxygenase and lipoxygenase pathways of AA metabolism in the formation of homosynaptic LTD in the rat hippocampus. Stimulation at 1 Hz for 15 min was used to produce homosynaptic depression in area CA1 of hippocampal slices. LTD induction was partially blocked by bromophenacyl bromide (50–100 μM), a selective PLA2 inhibitor, and by the a nonselective lipoxygenase inhibitor nordihydroguaiaretic acid (NDGA; 100 μM). In contrast, the specific cyclooxygenase blocker indomethacin (100 μM) did not significantly reduce hippocampal LTD. Since NDGA interferes with LTD formation, we examined whether specific inhibitors of 5- and 12-lipoxygenases were capable of blocking LTD expression. The 12-lipoxygenase inhibitor baicalein at a concentration of 50 μM reduced LTP formation when given in the bath, an effect that was less pronounced with the 5-lipoxygenase inhibitor AA-861. These data suggest that the activation of endogenous PLA2 and the formation of 12-lipoxygenase metabolites of AA may be important factors controlling the expression of hippocampal LTD.  相似文献   
69.
70.
PURPOSE: To examine whether compliance with underage sales laws by licensed retail establishments is related to underage use of commercial and social alcohol sources, perceived ease of obtaining alcohol, and alcohol use. METHODS: In 2005, alcohol purchase surveys were conducted at 403 off-premise licensed retail establishments in 43 Oregon school districts. A survey also was administered to 3,332 11th graders in the districts. Multi-level logistic regression analyses were used to examine relationships between the school district-level alcohol sales rate and students' use of commercial and social alcohol sources, perceived ease of obtaining alcohol, past-30-day alcohol use, and heavy drinking. RESULTS: The school district-level alcohol sales rate was positively related to students' use of commercial alcohol sources and perceived alcohol availability, but was not directly associated with use of social alcohol sources and drinking behaviors. Additional analyses indicated stronger associations between drinking behaviors and use of social alcohol sources relative to other predictors. These analyses also provided support for an indirect association between the school district-level alcohol sales rate and alcohol use behaviors. CONCLUSIONS: Compliance with underage alcohol sales laws by licensed retail establishments may affect underage alcohol use indirectly, through its effect on underage use of commercial alcohol sources and perceived ease of obtaining alcohol. However, use of social alcohol sources is more strongly related to underage drinking than use of commercial alcohol sources and perceived ease of obtaining alcohol.  相似文献   
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