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81.
Parkinson's disease (PD) is a major cause of disability. To date, there have been no large-scale efforts to measure the quality of PD care because of a lack of quality indicators for conducting an explicit review of PD care processes. We present a set of quality indicators for PD care. Based on a structured review of the medical literature, 79 potential indicators were drafted. Through a two-round modified Delphi process, an expert panel of seven movement disorders specialists rated each indicator on criteria of validity, feasibility, impact on outcomes, room for improvement, and overall utility. Seventy-one quality indicators met validity and feasibility thresholds. Applying thresholds for impact on outcomes, room for improvement, and overall utility, a subset of 29 indicators was identified, spanning dopaminergic therapy, assessment of functional status, assessment and treatment of depression, coordination of care, and medication use. Multivariable analysis showed that overall utility ratings were driven by validity and impact on outcomes (P < 0.01). An expert panel can reach consensus on a set of highly rated quality indicators for PD care, which can be used to assess quality of PD care and guide the design of quality improvement projects.  相似文献   
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OBJECTIVE: Given the limited availability of small-sized cryopreserved pulmonary homografts, we implanted a series of Shelhigh No-React porcine pulmonic valve conduits (SPVC). The aim of this study was to evaluate the short-term performance following implantation. METHODS: From February 2000 to September 2000, the SPVC was implanted 25 times in 24 patients in the right ventricular outflow tract (RVOT) to correct congenital anomalies. The anatomical malformations were TOF/PA in eight patients, TGA/VSD/PS in four, truncus arteriosus in four, IAA/VSD/AS or AA in four, l-TGA/VSD in two and other in two. Age at operation was 2.8+/-3.9 years (mean+/-SD), including 12 patients under 1 year. The median conduit size was 14mm (range, 10-18). RESULTS: At a mean follow-up of 23+/-5 months, two late deaths (8%) have occurred. Although they were not primarily conduit related, both showed severe conduit stenosis. Twenty-one conduits (84%) showed mild to severe conduit stenosis, regurgitation or both. Two patients underwent balloon dilatation for distal conduit stenosis. Twelve conduits (48%) in 11 patients were removed at a median of 12 months (range, 2-18 months) due to RVOT obstruction in 11 and free conduit insufficiency with pseudoaneurysm in one. The typical findings of the explanted conduits were prominent intimal peel formation at the distal anastomosis without calcification. The actuarial freedom from reintervention at 18 months was 48+/-10%. CONCLUSIONS: Our experience of the SPVC with the diameter of 14mm or less has revealed a high incidence of distal conduit stenosis due to intimal peel formation resulting in early conduit failure. These findings have led us to abandon its use when other options are available.  相似文献   
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Physicians who treat multiple sclerosis (MS) face the challenge of patients exhibiting ongoing disease activity, including exacerbations, loss of functional capabilities, intellectual decline, and radiologic progression, despite being on a disease-modifying agent (DMA). After searching for factors that might at least in part explain these changes—such as nonadherent drug-taking behavior, or the presence of interfer-on-neutralizing antibodies—some providers may ultimately decide to switch the patient to another DMA. In most circumstances, patients likely derive only partial effects from these agents, even in the absence of compromising factors. Thus, a number of factors must be considered in order to intensify the treatment regimen in response to disease progression. In the context of an inadequate treatment response to a DMA, some clinicians will convert the patient to an alternative therapy, and others will instead use a second agent in combination with the first (the so-called platform agent). In the first of this two-part series, we explored the use of anti-inflammatory CS and ACTH to treat MS exacerbations. Although we underscored the limited availability of evidence-based studies to support specific regimens for this purpose, there is an even greater paucity of data to support the routine use of these agents in order to achieve chronic disease-modifying effects in those who continue to deteriorate clinically, radiographically, or both. Without doubt, a number of factors influence the formulation of combination treatment plan for MS. Nevertheless, we will focus on the rationale and practical schemes that can be considered for using corticosteroids (CS) (and perhaps even ACTH) in an attempt to modify various domains of ongoing disease activity.  相似文献   
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Fluoranthene (FA) is frequently among the more abundant componentsdetected in environmental mixtures of polycyclic aromatic hydrocarbons.Several methylated fluoranthenes, although less prevalent thanFA, have also been detected as environmental pollutants. WhileFA is inactive as a tumorigenic agent on mouse skin, it doesinduce lung and liver tumors in newborn mice. Among the fiveisomers of methylfluoranthene, only 2-methylfluoranthene (2-MeFA)and 3-methylfluoranthene (3-MeFA) are active as tumor initiatorson mouse skin. A comparative bioassay was performed to determinethe relative tumorigenic activity of FA, 2-MeFA and 3-MeFA innewborn CD-1 mice. All three compounds were assayed at dosesof 3.46 and 17.3 µmol. The bioassay was terminated whenmice were 1 year old. At a dose of 17.3 µmol, FA and 2-MeFAinduced a similar incidence of lung tumors (65–96%) inboth male and female mice. However, tumor multiplicity in thelung was different between FA and 2-MeFA. At a dose of 17.3µmol, the multiplicity of lung tumors observed for miceadministered 2-MeFA ranged from 3.04 to 3.94 tumors per mouse.In contrast, animals treated with FA developed only an averageof 1.12–2.45 tumors per mouse. 3-MeFA did not induce astatistically significant incidence of lung tumors in eithermale or female mice. All three compounds when administered tonewborn mice did induce a significant incidence of liver tumorsamong male mice. The relative tumorigenic potency observed wasFA 5  相似文献   
86.
BACKGROUND: Repetitive transcranial magnetic stimulation (rTMS) affects the excitability of the motor cortex and is thought to influence activity in other brain areas as well. We combined the administration of varying intensities of 1-Hz rTMS of the motor cortex with simultaneous positron emission tomography (PET) to delineate local and distant effects on brain activity. METHODS: Ten healthy subjects received 1-Hz rTMS to the optimal position over motor cortex (M1) for producing a twitch in the right hand at 80, 90, 100, 110, and 120% of the twitch threshold, while regional cerebral blood flow (rCBF) was measured using H(2)(15)O and PET. Repetitive transcranial magnetic stimulation (rTMS) was delivered in 75-pulse trains at each intensity every 10 min through a figure-eight coil. The regional relationship of stimulation intensity to normalized rCBF was assessed statistically. RESULTS: Intensity-dependent rCBF increases were produced under the M1 stimulation site in ipsilateral primary auditory cortex, contralateral cerebellum, and bilateral putamen, insula, and red nucleus. Intensity-dependent reductions in rCBF occurred in contralateral frontal and parietal cortices and bilateral anterior cingulate gyrus and occipital cortex. CONCLUSIONS: This study demonstrates that 1-Hz rTMS delivered to the primary motor cortex (M1) produces intensity-dependent increases in brain activity locally and has associated effects in distant sites with known connections to M1.  相似文献   
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Background: During labor, ephedrine is widely used to prevent or to treat maternal arterial hypotension and restore uterine perfusion pressure to avoid intrapartum fetal asphyxia. However, the effects of ephedrine on uterine blood flow have not been studied during uterine contractions. The purpose of the study was to assess the effects of ephedrine on uterine artery velocities and resistance index using the Doppler technique during the active phase of labor.

Methods: Ten normotensive, healthy parturients with uncomplicated pregnancies at term received intravenous ephedrine during labor to increase mean arterial pressure up to a maximum of 20% above their baseline pressure. Peak systolic and end-diastolic Doppler flow velocities and resistance indices were measured in the uterine artery before and immediately after administration of bolus intravenous ephedrine and after ephedrine washout. Umbilical and fetal middle cerebral arterial resistance indices and fetal heart rate were also calculated.

Results: After ephedrine administration, mean arterial pressure increased by 17 +/- 4%. End-diastolic flow velocity in the uterine artery at peak amplitude of uterine contraction was restored to 74% of the value observed in the absence of contraction. The systolic velocity was totally restored, and the uterine resistance index was significantly decreased, compared with the values in the absence of contraction. Between uterine contractions, ephedrine induced similar but less marked effects. Fetal hemodynamic parameters were not altered by ephedrine administration.  相似文献   

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