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51.
There is limited research on the intake of non-nutritive sweeteners (NNS) among preschool-aged children. Canada’s Food Guide suggests limiting intake of NNS for all population groups and Health Canada recommends that young children (<2 years) avoid consuming beverages containing NNS. The aim of this study was to investigate the frequency and type of non-nutritive sweetener (NNS) intake in preschool-aged children participating in the Guelph Family Health Study pilots. Parents (n = 78 families) completed 3-day food records (n = 112 children; n = 55 females, n = 57 males; 3.6 years ± 1.3). Nineteen children (17%) reported consumption of foods or beverages containing NNS. Food sources with NNS included: freezies, oral nutritional supplements, flavored water, carbonated drinks, sugar free jam and protein powder. The majority of NNS contained in these foods were identified as stevia leaf extract, acesulfame K, sucralose, monk fruit extract and aspartame. Future research should continue to study NNS intake patterns longitudinally in children and examine the association of NNS intake with diet quality and health outcomes.  相似文献   
52.
The fetal femoral length and biparietal diameter were measured by ultrasound on 1657 occasions in 1289 singleton pregnancies between 12 and 41 weeks' gestation. Mean values for fetal femoral length were significantly lower than those demonstrated in previous studies, with the difference becoming greater approaching term. Three hundred twenty-two measurements of fetal femoral length were made on 57 patients with twin pregnancies, with no significant difference noted between the means of these recordings and the means of the singleton pregnancies.  相似文献   
53.
菊叶三七生物碱成分的研究   总被引:8,自引:0,他引:8  
从菊科蒂叶三七植物中分离出六个生物碱,对其中四个进行了鉴定。光谱数据证明:生物碱Ⅰ和Ⅱ分别为已知的千里光碱(senecionine,Ⅰ)和千里光菲灵碱(seneciphylline,Ⅱ),生物碱Ⅲ和Ⅳ为新成分,分别命名为菊三七碱甲(sineciphyllinine,Ⅲ)和菊三七碱乙[(E)-seneciphylline,Ⅳ]。  相似文献   
54.
Evidence-based neurosurgery   总被引:3,自引:0,他引:3  
Haines SJ 《Neurosurgery》2003,52(1):36-47; discussion 47
OBJECTIVE: The evidence-based medicine movement is gaining influence in many medical specialties. Although many think that clinical medicine always has been based on evidence, the discipline of evidence-based medicine places particular emphasis on a defined set of principles of critical analysis of individual research reports, methodologically rigorous synthesis of multiple reports, and the collection and dissemination of evidence repositories that allow rapid application of evidence in practice. This article provides a selective introduction to the discipline of evidence-based medicine as it applies to neurological surgery. METHODS: The vast literature on evidence-based medicine has been reviewed selectively to identify resources that are readable, accessible, and relevant to neurosurgery. RESULTS: The history, concepts, and techniques of evidence-based medicine are presented in brief, and educational and methodological resources, as well as evidence repositories, are introduced. CONCLUSION: The techniques of evidence-based medicine are relevant to neurological surgery. There is a relatively large repository of critically analyzed and summarized evidence that is useful to the neurosurgical practitioner. Familiarity with these techniques and repositories can help the neurosurgeon bring the best available evidence to bear on the care of individual patients.  相似文献   
55.
Catheter ablation therapy for atrial fibrillation   总被引:3,自引:0,他引:3  
Finta B  Haines DE 《Cardiology Clinics》2004,22(1):127-45, ix
The past several years have witnessed a significant growth in the number of institutions offering catheter ablation for atrial fibrillation (AF). This growth has been a result of a better understanding of pathophysiology of AF and use of instruments and approaches that made catheter ablation of AF a safe and an effective alternative to the drug therapy. The procedure increasingly is becoming a therapy of choice for a select group of symptomatic, drug-refractory patients without structural heart disease, and it is being offered to a rapidly widening patient pool. This article reviews the procedural aspects and clinical evidence supporting this wider use of AF ablation. In addition, new techniques and technologies for AF ablation and new avenues of research in this area are explored.  相似文献   
56.
The burden of chronic diseases, such as heart disease, cancer, diabetes, and mental disorders is high in low-income and middle-income countries and is predicted to increase with the ageing of populations, urbanisation, and globalisation of risk factors. Furthermore, HIV/AIDS is increasingly becoming a chronic disorder. An integrated approach to the management of chronic diseases, irrespective of cause, is needed in primary health care. Management of chronic diseases is fundamentally different from acute care, relying on several features: opportunistic case finding for assessment of risk factors, detection of early disease, and identification of high risk status; a combination of pharmacological and psychosocial interventions, often in a stepped-care fashion; and long-term follow-up with regular monitoring and promotion of adherence to treatment. To meet the challenge of chronic diseases, primary health care will have to be strengthened substantially. In the many countries with shortages of primary-care doctors, non-physician clinicians will have a leading role in preventing and managing chronic diseases, and these personnel need appropriate training and continuous quality assurance mechanisms. More evidence is needed about the cost-effectiveness of prevention and treatment strategies in primary health care. Research on scaling-up should be embedded in large-scale delivery programmes for chronic diseases with a strong emphasis on assessment.  相似文献   
57.
58.
To elucidate the functional and prognostic significance of right ventricular dysfunction after acute inferior wall myocardial infarction, 74 consecutive patients with inferior infarction were prospectively evaluated with gated equilibrium blood pool imaging at rest, submaximal exercise thallium-201 scintigraphy and coronary angiography before hospital discharge. In addition, symptom-limited stress thallium-201 scintigraphy was performed in 61 patients at 3 months, and all patients were followed up clinically for 23 +/- 15 months. Utilizing predetermined radionuclide angiographic criteria, 47 patients (Group I) had normal right ventricular function, 12 patients (Group II) had mild to moderate dysfunction and 15 patients (Group III) had severe right ventricular dysfunction. There were no significant differences among the groups with regard to age, history of prior myocardial infarction, peak creatine kinase values, maximal Killip functional class, number or type of in-hospital complications, left ventricular ejection fraction, prevalence of multivessel disease or the distribution and severity of disease affecting the infarct-related vessel. Exercise tolerance as assessed by treadmill time, blood pressure-heart rate product and peak work load in METS was comparable among the three groups, both before hospital discharge and at 3 month follow-up. No differences in indicators of exercise-induced ischemia were noted among the groups, including the prevalence of redistribution thallium-201 defects, ST segment depression or symptoms of chest pain. Finally, cardiac mortality, reinfarction rate and the incidence of medically refractory angina pectoris were similar in the three groups. Thus, right ventricular dysfunction after acute inferior wall myocardial infarction does not appear to limit exercise tolerance or identify a subgroup of patients at higher risk for recurrent cardiac events.  相似文献   
59.
Bioinformatics approaches to examine gene‐gene models provide a means to discover interactions between multiple genes that underlie complex disease. Extensive computational demands and adjusting for multiple testing make uncovering genetic interactions a challenge. Here, we address these issues using our knowledge‐driven filtering method, Biofilter, to identify putative single nucleotide polymorphism (SNP) interaction models for cataract susceptibility, thereby reducing the number of models for analysis. Models were evaluated in 3,377 European Americans (1,185 controls, 2,192 cases) from the Marshfield Clinic, a study site of the Electronic Medical Records and Genomics (eMERGE) Network, using logistic regression. All statistically significant models from the Marshfield Clinic were then evaluated in an independent dataset of 4,311 individuals (742 controls, 3,569 cases), using independent samples from additional study sites in the eMERGE Network: Mayo Clinic, Group Health/University of Washington, Vanderbilt University Medical Center, and Geisinger Health System. Eighty‐three SNP‐SNP models replicated in the independent dataset at likelihood ratio test P < 0.05. Among the most significant replicating models was rs12597188 (intron of CDH1)–rs11564445 (intron of CTNNB1). These genes are known to be involved in processes that include: cell‐to‐cell adhesion signaling, cell‐cell junction organization, and cell‐cell communication. Further Biofilter analysis of all replicating models revealed a number of common functions among the genes harboring the 83 replicating SNP‐SNP models, which included signal transduction and PI3K‐Akt signaling pathway. These findings demonstrate the utility of Biofilter as a biology‐driven method, applicable for any genome‐wide association study dataset.  相似文献   
60.
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