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91.
Study Objective . To determine the efficacy of high-dose ascorbate supplementation in lowering lipoprotein(a) [Lp(a)] levels in patients with premature coronary heart disease (CHD). Design . Randomized, double-blind, placebo-controlled trial. Setting . Outpatient clinic. Patients . Forty-four patients with documented premature CHD. defined as confirmed myocardial infarction and/or angiographically determined stenosis of 50% or greater in at least one major coronary artery before age 60 years. Interventions . Patients were block randomized on the basis of age, gender, and screening Lp(a) concentrations to receive ascorbate 4.5 g/day or placebo for 12 weeks. Measurements and Main Results . High-dose ascorbate was well tolerated and produced a marked elevation in mean plasma ascorbate levels (+1.2 mg/dl; p<0.001). Multiple linear regression analysis revealed no significant effect of supplementation on postintervention Lp(a) levels (p=0.39) in a model that included treatment group assignment, and baseline Lp(a) levels. Conclusions . Our findings do not support a clinically important lowering effect of high-dose ascorbate on plasma Lp(a) in patients with premature CHD.  相似文献   
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Diagnosis and management of anaphylaxis   总被引:7,自引:0,他引:7       下载免费PDF全文
ANAPHYLAXIS IS A SEVERE SYSTEMIC ALLERGIC reaction that is potentially fatal. It requires prompt recognition and immediate management. Anaphylaxis has a rapid onset with multiple organ–system involvement and is mostly caused by specific antigens in sensitized individuals. Reactions typically follow a uniphasic course, however, 20% will be biphasic in nature. The second phase usually occurs after an asymptomatic period of 1–8 hours, but there may be a 24-hour delay. Protracted anaphylaxis may persist beyond 24 hours. Concurrent β-blocker therapy may adversely affect the response to management. Epinephrine is the treatment of choice and should be administered immediately. Secondary measures include circulatory support, H1 and H2 antagonists, corticosteroids and, occasionally, bronchodilators. Post-treatment observation of these patients is necessary, and they should remain within ready access of emergency care for the following 48 hours.  相似文献   
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Background: Tibialis posterior is a frequent cause of an acquired flatfoot deformity and the prevalence is not known. If tibialis posterior dysfunction was found to occur frequently, a greater awareness may result leading to earlier patient diagnosis, referral and treatment.Objectives: To validate a screening questionnaire for tibialis posterior dysfunction, and to investigate the prevalence of tibialis posterior dysfunction in a high-risk patient population.Methods: The screening questionnaire was given prospectively to 65 patients (44 females, 21 males; mean age 79.6 years) attending an unrelated care of the elderly appointment. A foot and ankle surgery fellow separately examined all feet for tibialis posterior dysfunction.Results: The survey was 100% sensitive and 98.3 % specific at detecting tibialis posterior dysfunction. Six of the 65 patients (5 females, 1 male) had tibialis posterior dysfunction, and two had bilateral involvement. All six of the patients had longstanding symptoms, all had consulted their doctor and three had seen an orthopaedic surgeon; only one of the six patients had been correctly diagnosed.Conclusions: This study suggests that tibialis posterior dysfunction occurs frequently, but is seldom diagnosed in elderly women. Further epidemiologic studies are needed to determine the true prevalence.  相似文献   
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Couples in remarriages with stepchildren are a significant portion of the marriage population and have unique educational needs regarding aspects of couple functioning within the context of stepfamily development. From a review of the literature, we examine current curricula focused on these couples. Information is offered on implementation issues regarding recruitment, delivery context, facilitator and participant characteristics, and evaluation.  相似文献   
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This study investigates functional disability among some of the nation's most vulnerable older adults: rural Medicaid recipients. Data were provided by 221 older adults (mean age = 75.9 years; 82% women) who were receiving community-based long-term care services through Medicaid. Participants self-reported functional ability involving the completion of six basic activities of daily living (BADLs), three cognitive instrumental activities of daily living (IADLS), and four physical IADLs. Self-reports of depressed affect and the number of physical health conditions were also obtained. Path analysis was used to examine all of the associations among age, gender, number of chronic health conditions, depressed affect and functional disability. The tested model was significant [chi2 (DF = 3, n = 221) = 5.052, p = 0.168; TLI = 0.945; CFI = 0.992; RMSEA = 0.056] and explained 45.1% of the variance in BADL disability. Depressed affect significantly predicted disability in cognitive IADLs and physical IADLs, which predicted disability in BADLs. Age and gender had indirect effects on BADL, through their association with cognitive IADLs and physical IADLs. The number of chronic health conditions exerted both indirect and direct effects on BADL disability. Results are discussed within the context of the growing literature that suggests the importance of psychological variables as predictors of functional disability. Moreover, we discuss whether community-based long-term care is appropriate for older adults with high levels of functional disability.  相似文献   
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