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991.
992.
The mission of the Veterans Health Administration's (VHA) quality enhancement research initiative (QUERI) is to enhance the quality of VHA health care by implementing clinical research findings into routine care. This paper presents lessons that QUERI investigators have learned through their initial attempts to pursue the QUERI mission. The lessons in this paper represent those that were common across multiple QUERI projects and were mutually agreed on as having substantial impact on the success of implementation. While the lessons are consistent with commonly recognized ingredients of successful implementation efforts, the examples highlight the fact that, even with a thorough knowledge of the literature and thoughtful planning, unexpected circumstances arise during implementation efforts that require flexibility and adaptability. The findings stress the importance of utilizing formative evaluation techniques to identify barriers to successful implementation and strategies to address these barriers.  相似文献   
993.
OBJECTIVES: We sought to evaluate whether the clustering of multiple components of the metabolic syndrome (MS) has a greater impact on these vascular parameters than individual components of MS. BACKGROUND: Intima-media thickness (IMT) and vascular stiffness have been shown to be independent predictors of adverse cardiovascular events. The MS is defined as the clustering of three or more of the cardiovascular risk factors of dysglycemia, hypertension, dyslipidemia, and obesity. METHODS: Carotid IMT and stiffness were derived via B-mode ultrasonography in 471 participants from the Baltimore Longitudinal Study on Aging, who were without clinical cardiovascular disease and not receiving antihypertensive therapy. RESULTS: The MS conferred a disproportionate increase in carotid IMT (+16%, p < 0.0001) and stiffness (+32%, p < 0.0001), compared with control subjects. Multiple regression models, which included age, gender, smoking, low-density lipoprotein, as well as each individual component of MS as continuous variables, showed that MS was an independent determinant of both IMT (p = 0.002) and stiffness (p = 0.012). The MS was associated with a greater prevalence of subjects whose values were in the highest quartiles of IMT, stiffness, or both. CONCLUSIONS: Even after taking into account each individual component of MS, the clustering of at least three of these components is independently associated with increased IMT and stiffness. This suggests that the components of MS interact to synergistically impact vascular thickness and stiffness. Future studies should examine whether the excess cardiovascular risk associated with MS is partly mediated through the amplified alterations in these vascular properties.  相似文献   
994.
BACKGROUND: Prior research has found that dementia is often undiagnosed in primary care, but there has been limited research on whether physicians respond to symptoms, behaviors, or other events that may be indicators of dementia. METHODS: A cross-sectional cohort study design was used to screen 553 patients aged 75 years or older for dementia in 3 managed health care systems in Portland, Oregon. For participants determined to be cognitively impaired, their medical charts were reviewed to determine if they had experienced adverse events, had been clinically evaluated for possible dementia, had received a diagnosis of dementia, or had been offered treatment. RESULTS: Nearly 43% of participants were identified as cognitively impaired: 29.7% were classified as mildly cognitively impaired (MI) and 13.7% as moderately to severely cognitively impaired (MSI). Eighteen percent of the MI group and 34.8% of the MSI group had evidence in their medical chart of having been clinically evaluated for dementia. None of the MI group and only 4.3% of the MSI group had been offered a cholinesterase inhibitor. Nearly two thirds (61.6%) of the MI and three fourths (75.4%) of the MSI participants had experienced 1 or more adverse events. Of those who had experienced adverse events, less than one quarter (23.7%) in the MI group and less than one half (44.2%) in the MSI group had received a clinical evaluation for dementia. CONCLUSIONS: These findings suggest the need for greater attention by primary care physicians to the cognitive functioning of older patients, especially patients who experience adverse events that may be indicators of dementia.  相似文献   
995.
OBJECTIVE: Vitamin D is a potent regulator of calcium homeostasis and may have immunomodulatory effects. The influence of vitamin D on human autoimmune disease has not been well defined. The purpose of this study was to evaluate the association of dietary and supplemental vitamin D intake with rheumatoid arthritis (RA) incidence. METHODS: We analyzed data from a prospective cohort study of 29,368 women of ages 55-69 years without a history of RA at study baseline in 1986. Diet was ascertained using a self-administered, 127-item validated food frequency questionnaire that included supplemental vitamin D use. Risk ratios (RRs) and 95% confidence intervals (95% CIs) were estimated using Cox proportional hazards regression, adjusting for potential confounders. RESULTS: Through 11 years of followup, 152 cases of RA were validated against medical records. Greater intake (highest versus lowest tertile) of vitamin D was inversely associated with risk of RA (RR 0.67, 95% CI 0.44-1.00, P for trend = 0.05). Inverse associations were apparent for both dietary (RR 0.72, 95% CI 0.46-1.14, P for trend = 0.16) and supplemental (RR 0.66, 95% CI 0.43-1.00, P for trend = 0.03) vitamin D. No individual food item high in vitamin D content and/or calcium was strongly associated with RA risk, but a composite measure of milk products was suggestive of an inverse association with risk of RA (RR 0.66, 95% CI 0.42-1.01, P for trend = 0.06). CONCLUSION: Greater intake of vitamin D may be associated with a lower risk of RA in older women, although this finding is hypothesis generating.  相似文献   
996.
Time course of the interaction between tadalafil and nitrates   总被引:4,自引:0,他引:4  
OBJECTIVES: This study was designed to determine the time course of nitrate interaction with tadalafil, a phosphodiesterase 5 (PDE5) inhibitor with a half-life (t(1/2)) of 17.5 h. BACKGROUND: The PDE5 inhibitors augment the blood pressure (BP)-lowering effects of nitrates, yet the time course of this interaction is unclear. Recent guidelines from the American College of Cardiology/American Heart Association recommend that nitrates be withheld for 24 h after taking sildenafil (t(1/2) = 4 h). METHODS: Male subjects (n = 150) received seven consecutive daily doses of placebo or tadalafil (20 mg). On day 7 and beyond, subjects received repeated doses of sublingual nitroglycerin (0.4 mg) after the last dose of placebo or tadalafil. After a 10- to 21-day washout period, subjects crossed over to either placebo or tadalafil, and nitrate dosing was repeated. RESULTS: In response to nitroglycerin at 4, 8, and 24 h, standing systolic BP fell below 85 mm Hg in more subjects on tadalafil compared with placebo (p < 0.05), with no difference in the response to nitroglycerin at 48, 72, and 96 h (p > 0.2). Similar observations were made for standing diastolic BP <45 mm Hg, decrease in systolic BP >30 mm Hg, and decrease in diastolic BP >20 mm Hg. Nitroglycerin also evoked greater mean maximal decreases in standing systolic BP at 8 and 24 h after taking tadalafil versus placebo (p < 0.02), with no significant difference at 48, 72, or 96 h (p > 0.49). CONCLUSIONS: The hemodynamic interaction between tadalafil and sublingual nitroglycerin lasted 24 h, but was not seen at 48 h and beyond. Similar to other PDE5 inhibitors, tadalafil should not be administered in combination with organic nitrates.  相似文献   
997.
We defined interpopulation differences in the frequency of the dopamine D2 receptor DRD2/Taq1 A1 allele, which has previously been associated with alcoholism. Frequencies of the A1 allele in unrelated subjects were 0.18 to 0.20 (se = 0.02 to 0.03) in several Caucasian populations previously assessed, 0.38 (±0.05) in American Blacks ( n = 44), 0.63 (±0.07) in Jemez Pueblo Indians ( n = 23), and 0.80 (± 0.04) in Cheyenne Indians ( n = 52). The existence of large interpopulation differences in the frequency of the Taq1 alleles suggests that associations to disease status could readily be generated or masked if disease and control groups were uneven in ethnic composition. To address the possibility that the 4-fold higher frequency of the A1 allele in Cheyenne Indians was related to an increased vulnerability to alcoholism in that population, 47 Cheyenne Indians were psychiatrically interviewed and blind-rated. However, there was no significant difference between interviewed controls (0.73 ± 0.06, n = 24), subjects with alcoholism and/or drug abuse (0.74 ± 0.06, n = 23) and noninterviewed population controls (0.87 ± 0.05, n = 20). Legitimate association of the DRD2/Taq1 allele to alcoholism would presumably require it to be in linkage disequilibrium (nonrandom association) with a functional mutation at DRD2 or elsewhere. The level of disequilibrium would vary between populations and could place an upper bound on the strength of an association. To provide a model for the extent and variation of disequilibrium at DRD2, the level of linkage disequilibrium between the Taq1 RFLP and a second DRD2 polymorphism, the SSCP variant in the immediate 3'region of the gene, was determined in three populations. The normalized disequilibrium values were 0.36 In U.S. Caucasians ( n = 48), 0.34 in Finns ( n = 86), and 0.78 in Cheyenne Indians ( n = 34).  相似文献   
998.
999.
ContextOlder adults with advanced cancer face uncertainty related to their disease and treatment.ObjectivesTo evaluate the associations of uncertainty with psychological health and quality of life (QoL) in older adults with advanced cancer.MethodsSecondary cross-sectional analysis of baseline data from a national clustered geriatric assessment trial. Patients 70 years and older with advanced cancer considering a new line of chemotherapy were recruited. We measured uncertainty using the modified nine-item Mishel Uncertainty in Illness Scale. Dependent variables included anxiety (Generalized Anxiety Disorder-7), depression (Generalized Depression Scale-15), distress (distress thermometer), QoL (Functional Assessment of Cancer Therapy—General), and emotional well-being (Functional Assessment of Cancer Therapy—General subscale). We used multivariate linear regression analyses to evaluate the association of uncertainty with each dependent variable. We conducted a partial least squares analysis with a variable importance in projection (VIP) plot to assess the contribution of individual variables to the model. Variables with a VIP <0.8 were considered less influential.ResultsWe included 527 patients (median age 76 years; range 70–96). In multivariate analyses, higher levels of uncertainty were significantly associated with greater anxiety (β = 0.11; SE = 0.04), depression (β = 0.09; SE = 0.02), distress (β = 0.12; SE = 0.02), as well as lower QoL (β = ?1.08; SE = 0.11) and emotional well-being (β = ?0.29; SE = 0.03); the effect sizes were considered small. Uncertainty items related to disease and treatment were most strongly associated with psychological health and QoL scores (all VIP >0.8).ConclusionUncertainty among older patients with advanced cancer is associated with worse psychological health and QoL. Tailored uncertainty management strategies are warranted.  相似文献   
1000.
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