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991.
The objective of our study was to determine the influence of gender and age of onset on the outcome in Saudi children with systemic lupus erythematosus (SLE). Medical records of children with SLE treated at King Faisal Specialist Hospital and Research Center were reviewed. Outcome measures included Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index score (SLICC/ACR), renal disease requiring dialysis, or transplant and death related to SLE. Patients were classified based on age at disease onset into early onset (<5 years) and late onset (>5 years). Data were analyzed, and comparison was made according to the gender and age groups. Eighty-nine patients (76 female and 13 male) were included. The median disease duration was 5 years. Twelve patients had early-onset disease. There was no difference in the mean age, age at diagnosis, disease duration, and follow-up between the different groups. Logistic regression analysis showed significant association of high SLICC/ACR score with early-onset disease and male gender, while renal disease requiring dialysis and renal transplant was associated significantly with male gender independently of age of disease onset. In contrast, death related to SLE was influenced by early-onset disease. Male children and early onset disease of this cohort had poorer outcome. This finding indicates that gender and early-onset disease influence the long-term outcome of SLE in children.  相似文献   
992.
The authors first describe the rules enacted in Quebec and France to protect adults with decisional impairment who may be approached by investigators to participate in research protocols. They then present two consecutive postal surveys conducted among Quebec and French researchers in aging and designed to (1) assess their knowledge of the legal provisions implemented to protect decisionally incapable adults, (2) elicit their opinions regarding the person best suited to provide substitute consent for research participation, and (3) document their conduct related to obtaining consent for prospective subjects with impaired decisional capacity. Knowledge of the legislation governing substitute consent was poor, even more so among French than Quebec researchers (p < 0.001). In both samples, the majority of respondents felt that the substitute decision-maker does not have to be legally appointed when the study poses little risk to the participant. Practice data revealed a certain discrepancy between the conduct of researchers in aging and the legal provisions regarding consent for research purposes that prevail in their jurisdictions. These findings underscore the need to better educate clinical investigators about existing measures to protect prospective subjects who lack decisional capacity. They also provide some support for allowing close relatives to consent to research participation on behalf of older adults who are unable to consent by themselves and have not been appointed a legal representative.  相似文献   
993.
Atherosclerotic carotid artery stenosis is a major cause of disabling stroke or death. Although carotid endarterectomy (CEA) is currently considered to be the standard of care for patients with a severe symptomatic stenosis and selected patients with an asymptomatic carotid stenosis, carotid angioplasty and stenting (CAS) is increasingly being used as an alternative treatment modality. This article briefly summarizes the current trial data on CEA and CAS. More importantly, potential risk factors for CEA and CAS are reviewed and the complementary role of these techniques in the management of the individual patient is discussed.  相似文献   
994.

Background  

Human immunodeficiency virus infected individuals are prone to malnutrition due to increased energy requirements, enteropathy and increased catabolism. Trace elements such as zinc and selenium have major role in maintaining a healthy immune system. This study was designed to evaluate the nutritional status of Iranian subjects who were newly diagnosed with human immunodeficiency virus infection and to compare serum level of zinc and selenium in these patients with those of the sex and aged match healthy subjects.  相似文献   
995.
Voltage-gated Na(+) channels are composed of pore-forming alpha and auxiliary beta subunits. The majority of Na(+) channels in the heart contain tetrodotoxin (TTX)-insensitive Na(v)1.5 alpha subunits, but TTX-sensitive brain-type Na(+) channel alpha subunits are present and functionally important in the transverse tubules of ventricular myocytes. Sinoatrial (SA) nodal cells were identified in cardiac tissue sections by staining for connexin 43 (which is expressed in atrial tissue but not in SA node), and Na(+) channel localization was analyzed by immunocytochemical staining with subtype-specific antibodies and confocal microscopy. Brain-type TTX-sensitive Na(v)1.1 and Na(v)1.3 alpha subunits and all four beta subunits were present in mouse SA node, but Na(v)1.5 alpha subunits were not. Na(v)1.1 alpha subunits were also present in rat SA node. Isolated mouse hearts were retrogradely perfused in a Langendorff preparation, and electrocardiograms were recorded. Spontaneous heart rate and cycle length were constant, and heart rate variability was small under control conditions. In contrast, in the presence of 100 nM TTX to block TTX-sensitive Na(+) channels specifically, we observed a significant reduction in spontaneous heart rate and markedly greater heart rate variability, similar to sick-sinus syndrome in man. We hypothesize that brain-type Na(+) channels are required because their more positive voltage dependence of inactivation allows them to function at the depolarized membrane potential of SA nodal cells. Our results demonstrate an important contribution of TTX-sensitive brain-type Na(+) channels to SA nodal automaticity in mouse heart and suggest that they may also contribute to SA nodal function and dysfunction in human heart.  相似文献   
996.
Hypertension and hypercholesterolemia are frequently associated, and their treatment is proven to reduce cardiovascular risk. Current guidelines on cardiovascular prevention strongly recommend treating both disorders. Unfortunately, the low treatment and control rates, combined with the high prevalence of both conditions, still contribute to the high burden of cardiovascular disease in Western countries. In the past 5 years, many studies evaluating the benefit of combined antihypertensive and lipid-lowering treatment on endothelial dysfunction, coronary atherosclerosis, hypertension control, and on primary and secondary prevention of cardiovascular events have been published. In this article, we discuss and critically evaluate the available evidence on the potential benefits of combined antihypertensive and lipid-lowering treatment.  相似文献   
997.
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999.
OBJECTIVE: To evaluate the dose-related benefit of angiotensin-converting enzyme (ACE) inhibitor therapy among older adults with heart failure and to evaluate whether low-dose ACE inhibitor therapy is better than none. DESIGN: Observational cohort study. SETTING: Community-dwelling older adults in Ontario, Canada. PATIENTS/PARTICIPANTS: We identified 16539 adults 66 years or older who survived 45 days following their first heart failure hospitalization discharge. MEASUREMENT AND MAIN RESULTS: Multivariate techniques including propensity scores were used to study the association between the dose of ACE inhibitor therapy dispensed and 3 outcomes: survival, survival or heart failure rehospitalization, and survival or all-cause hospitalization at 1 year of follow-up. Logistic regression models explored the association between initial dose dispensed and subsequent dose reduction or drug cessation. Overall, 10793 (65.3%) of patients were dispensed ACE inhibitor therapy, with more than a third (3935; 36.5%) initiated on low-dose therapy. Relative to dispensing of low-dose ACE inhibitor therapy, nonuse was associated with increased mortality (hazard ratio [HR], 1.12; 95% confidence interval [CI], 1.02 to 1.22). Dispensing medium-dose therapy provided a benefit similar to low-dose (HR, 0.94; CI, 0.86 to 1.03) and dispensing of high-dose therapy was associated with improved survival benefit (HR, 0.76; CI, 0.68 to 0.85). Relative to dispensing of low-dose ACE inhibitor therapy, dispensing high-dose conferred a benefit (HR, 0.87; CI, 0.80 to 0.95) on the composite outcome of 1-year mortality or heart failure hospitalization and the composite outcome of 1-year mortality or all-cause hospitalization (HR, 0.87; CI, 0.81 to 0.93). Relative to those dispensed low-dose ACE inhibitor therapy, those initially dispensed high-dose therapy were twice as likely to have their subsequent dose reduced or the therapy discontinued (odds ratio, 2.36; CI, 2.07 to 2.69). CONCLUSION: Our findings suggest that when possible, older adults should be titrated to the higher doses of ACE inhibitor therapy evaluated in clinical trials. If older adults cannot tolerate higher doses, then low-dose ACE inhibitor therapy is superior to none. High-dose ACE inhibitor therapy is not as well tolerated as lower doses.  相似文献   
1000.
PURPOSE: Chronic anal fissure may be treated by chemical or surgical sphincterotomy. The aim of this study was to test the efficacy of local application of nifedipine and lidocaine ointment in healing chronic anal fissure. METHODS: The study was performed according to a prospective, randomized, double-blind design. One hundred ten patients who gave informed consent were recruited. They received a clinical examination, a questionnaire to evaluate symptoms and pain, anorectal manometry, and anoscopy. Healing of anal fissure at Day 42 of therapy was defined as the primary efficacy variable of the study. Patients treated with nifedipine (n = 55) used topical 0.3 percent nifedipine and 1.5 percent lidocaine ointment every 12 hours for 6 weeks. The control group (n = 55) received topical 1.5 percent lidocaine and 1 percent hydrocortisone acetate ointment during therapy. Anal pressures were measured by recording resting and maximal voluntary contraction pressures at baseline and at Day 21. Long-term outcomes were determined after a median follow-up of 18 months. RESULTS: Healing of chronic anal fissure was achieved after 6 weeks of therapy in 94.5 percent of the nifedipine-treated patients (P < 0.001) as opposed to 16.4 percent of the controls. Mean anal resting pressure decreased from a mean value +/- standard deviation of 47.2 +/- 14.6 to 42 +/- 12.4 mmHg in the nifedipine group. This represents a mean reduction of 11 percent (P = 0.002). Changes of maximal voluntary contraction in nifedipine-treated patients were not significant. No changes in mean anal resting pressure and maximal voluntary contraction were observed in the control group. We did not observe any systemic side effect in patients treated with nifedipine. After the blinding was removed, recurrence of the fissure was observed in 3 of 52 patients in the nifedipine group within 1 year of treatment, and 2 of these patients healed with an additional course of topical nifedipine and lidocaine ointment. CONCLUSIONS: Our study clearly demonstrates that the therapeutic use of topical nifedipine and lidocaine ointment should be extended to the conservative treatment of chronic anal fissure.  相似文献   
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