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101.
The Studies of Left Ventricular Dysfunction (SOLVD) trials were designed to evaluate the effects of enalapril on long-term mortality in patients with severe left ventricular (LV) dysfunction. Patients with LV ejection fractions less than or equal to 0.35 and symptoms of congestive heart failure (CHF) were enrolled in the treatment trial, whereas those with no history of overt CHF and taking no treatment directed for LV dysfunction were enrolled in the prevention trial. The baseline clinical characteristics of SOLVD patients were compared to characterize differences between patients in these 2 separate but concurrent trials. From over 70,000 patients screened with LV dysfunction, 4,228 patients were enrolled in the prevention trial and 2,569 patients in the treatment trial. Ischemic heart disease was the primary cause of LV dysfunction in both prevention (83%) and treatment (71%) trial patients. Prior myocardial infarction was present in 80% of the prevention and 66% of the treatment trial patients (p less than 0.001). In the prevention trial, infarction was recent (less than or equal to 6 months) in 27% patients and remote (greater than 6 months) in 57% patients. Treatment trial patients had proportionately more women (20 vs 13%; p less than 0.001) and non-Caucasians (20 vs 14%; p less than 0.001), as well as the coexisting risk factors of hypertension (42 vs 37%; p less than 0.001) and diabetes (26 vs 15%; p less than 0.001) than did prevention trial patients. Clinical characteristics of patients in both trials were influenced by the gender and race of enrolled patients. Similarly, coronary artery bypass surgery was performed less often in women and non-Caucasians.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
102.
During an exposure monitoring study, 78 saw maintenance tradesmen were randomly assigned to be interviewed about their exposures using one of two questionnaire formats: open-ended and partly prompted questions about five categories of materials; and detailed prompting about 75 agents. The more open-ended questionnaire elicited fewer exposure responses overall, but more responses about agents not included on the detailed questionnaire. Composite materials and trade name products were more frequently cited as exposures than individual metals or compounds. Validity of responses was ascertained using air measurements (individual metals) or observations of the employees (composite materials). Sums of sensitivities and specificities were very low (near 1.0) for most of the metals for both types of questionnaire. For composite materials, validity improved substantially. Sensitivities with the partly prompted format (0.44–0.85) were always lower than with detailed prompting (0.80–1.00). Specificities were usually, but not always, higher with partial prompting (0.66–0.92) than with detailed prompting (0.18–0.86). Selection of questionnaire format for an epidemiologic study would depend on the likely prevalence of exposure in controls and the effects of trade-offs in sensitivity and specificity.  相似文献   
103.
104.
A limited flip angle gradient-echo 3D volume acquisition imaging protocol for mapping partial pressure of oxygen (pO2) in perfluorocarbon compounds (PFCs) at low field (0.14 T) is presented. The pO2 measurement method is based on the paramagnetic effect of dissolved molecular oxygen (O2) which reduces the PFC 19F T1? Specific objectives related to imaging of PFCs through use of the protocol include improved image signal-to-noise characteristics and elimination of 19F chemical shift artifacts. A parametric Wiener deconvolution filtering algorithm is used for suppression of 19F chemical shift artifacts. Application of the protocol is illustrated in a series of calculated pO2 maps of a gas equilibrated, multi-chamber phantom containing perfluorotributylamine (FC-43). The utility of the protocol is demonstrated in vivo through images of a commercially available perfluorocarbon based blood substitute emulsion containing FC-43 sequestered in the liver and spleen of a rat.  相似文献   
105.
106.
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   
107.
We assessed the inter-rater reliability of the 100-point International Cooperative Ataxia Rating Scale (ICARS). Three neurologists independently rated videotaped ICARS examinations of 22 subjects with genetically determined ataxias (spinocerebellar ataxia [SCA] Type 1 in 11; SCA Type 2 in 1; Friedreich's ataxia in 10) and 4 controls. Scores on live ICARS assessment had ranged from 0 to 7 for controls and 11 to 74 for ataxic subjects (clinically very mildly affected to wheelchair-bound). Inter-rater correlation was very high for the total score (Kendall's omega 0.994, 95% confidence interval, 0.988-0.997), and high to very high for each component subscore (0.791 for speech to 0.994 for posture/gait). All correlations were significant at P < 0.00001. The ICARS exhibits very high inter-rater reliability even without prior observer standardisation and is sensitive to a range of ataxia severities from very mild to severe.  相似文献   
108.
Pharmacy and therapeutics committees commonly cite a lack of generalizability as a reason for not incorporating cost-effectiveness information into decision making. To address this concern, many committees undertake site-specific economic evaluations, which are often limited by small sample sizes and nonrandomized designs. We show how 2 complementary approaches were used to minimize these limitations in an economic evaluation of abciximab at 1 institution. Using a propensity score methodology, we selected patients who did not receive abciximab for the comparison cohort. Then, we adopted a Bayesian, hierarchical, random-effects model to integrate site-specific and clinical trial data. We applied the posterior distributions of effectiveness with local cost data in a traditional decision-analytic model. In 74% of the simulations, abciximab was cost-effective at 1 institution at the $50,000 per life year saved threshold, assuming a 50:50 split of patients undergoing coronary stenting and angioplasty. Among patients undergoing coronary stenting, the cost-effectiveness ratio of the addition of abciximab was at or below the $50,000 per life year saved threshold in 66.0% of the simulations.  相似文献   
109.
Insulin lispro is an insulin analogue that has the advantages of being fast-acting, convenient, and less likely to lead to hypoglycaemic episodes. Previous studies have proven its value in treating both Type 1 and Type 2 diabetes both alone and in combination with different treatment regimens.1,2 However, diabetes is heterogeneous and differs in etiology and clinical characteristics in different ethnic groups. Even with the same insulin treatment, different diets will produce different glycaemic profiles. Diet patterns differ between different ethnic groups. Traditional oriental foods are characterized by a higher proportion of carbohydrates and a lower proportion of fat compared to Caucasian diets. To date, there has been no study on the use of insulin lispro in Chinese diabetic patients. Whether the Chinese dietary pattern will affect the efficacy of insulin lispro treatment remains unknown. Therefore, we conducted this trial to assess the efficacy of insulin lispro treatment in Chinese patients.  相似文献   
110.
BACKGROUND: Elevated cortisol levels might account for the reduction in central serotonin 1A (5-hydroxytryptamine [5-HT](1A)) receptor binding and function observed in patients with major depression. We tested this hypothesis by studying the effect of acute administration of hydrocortisone on 5-HT(1A) receptor binding potential (BP) in subjects recovered from depression. METHODS: We studied 14 subjects (8 male, 6 female) who had recovered from at least two episodes of major depression and had been euthymic and drug free for at least 6 months. Serotonin 1A receptor BP was measured by [(11)C]WAY-100635 in conjunction with positron emission tomography. Subjects were tested on two occasions in a double-blind, random-order, crossover design after administration of either hydrocortisone (100 mg orally) or placebo 12 hours previously. Positron emission tomography scans were analyzed with a region of interest analysis. RESULTS: Hydrocortisone treatment did not decrease 5-HT(1A) receptor BP either in the hippocampus, which was our a priori hypothesis, or in other cortical 5-HT(1A) regions; however, female subjects had a higher 5-HT(1A) receptor BP in certain brain areas compared with male subjects. CONCLUSIONS: These data are consistent with an earlier study in healthy volunteers and do not support the proposal that decreased 5-HT(1A) receptor BP in patients with acute major depression is a consequence of cortisol hypersecretion.  相似文献   
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