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排序方式: 共有1522条查询结果,搜索用时 15 毫秒
41.
Ellen R. Lambert Dimitrios A. Koutoukidis Sarah E. Jackson 《Obesity research & clinical practice》2019,13(6):571-578
ObjectivesTo investigate the effect of weight stigma in news media on (a) intentions to increase physical activity (PA), improve diet quality and lose weight, and (b) changes in PA, diet quality and body mass index (BMI) over one month, in (i) women of all weight categories and (ii) a subsample of women living with obesity.MethodsUK-based women (N = 172; subgroup with obesity N = 81) were assigned to read an experimental (weight stigma; N = 75) or control (smoking stigma; N = 97) news article. Questionnaires were administered immediately after, and one month subsequently to collect information on BMI, PA, diet quality, intentions, past stigma, and diet and PA self-efficacy. Logistic and linear regression analyses were used to assess the effect of weight stigma on all outcome variables.ResultsIn the whole sample, there was no significant effect of weight stigma on any primary or secondary outcome. In women with obesity, there was no significant effect of weight stigma on diet quality (0.26 units, 95% CI: ?0.36 to 0.87) or PA (?1.83 units, 95% CI: ?11.11 to 7.44) at follow up, but exposure to weight stigma was associated with a significant increase in BMI at 1-month follow-up (1.15 kg/m2, 95% CI: 0.38 to 1.92) compared with the control group.ConclusionsIn people with obesity, exposure to weight-stigmatising media may contribute to increased BMI over time. Larger trials with longer follow-up are needed to confirm these findings. 相似文献
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Background
Evidence on adverse effects of maternal macrolide use during pregnancy is inconsistent. We conducted a systematic review and meta-analysis to investigate the association between macrolide use during pregnancy and adverse fetal and child outcomesMethods
We searched PubMed, Embase, the Cochrane Library, Conference Proceeding Citation Index-Science, and ClinicalTrials.gov from inception to Feb 15, 2018, with no language restrictions. We included observational studies and randomised controlled trials (RCTs) that recorded macrolide use during pregnancy and fetal and child outcomes. We prioritised comparisons of macrolides with alternative antibiotics (mainly penicillins or cephalosporins) for indication and effect. Secondary analysis included RCTs that compared macrolide use with placebo and macrolide use plus alternative antibiotics with the same alternatives. Random effects meta-analysis was used to derive pooled odds ratios (OR) for each outcome. We described heterogeneity according to comparators (other antibiotics or placebo) and type of macrolide.Findings
Of 11?186 citations identified, 19 studies (ten observational, nine RCTs) were included (21 articles with 228?556 participants). Macrolide prescribing during pregnancy was associated with an increased risk of miscarriage (pooled OR 1·82, 95% CI 1·57–2·11; I2=0% [three observational studies]), cerebral palsy or epilepsy (1·78, 1·18–2·69; one observational study), epilepsy alone (2·02, 1·30–3·14 [one observational study]; 1·03, 0·79–1·35 [two RCTs]), and gastrointestinal malformations (1·56, 1·05-2·32; two observational studies) compared with alternative antibiotics. We found no evidence of an adverse effect on 12 other malformations, stillbirth, or neonatal death. Secondary analyses showed similar results to those from the primary analysis. Results were robust to excluding studies with high risk of bias.Interpretation
Our findings of an increased risk of miscarriage cannot be explained by indication bias. Consistent evidence of an increased risk of miscarriage in observational studies and uncertain risks of cerebral palsy and epilepsy warrant cautious use of macrolide in pregnancy with warnings in drug safety leaflets and use of alternative antibiotics where appropriate. Since macrolides are the third most commonly used class of antibiotics, it is important to confirm these results with high-quality studies.Funding
Economic and Social Research Council (grant ES/L007517/1). Child Health Research CIO (CHR CIO) Trust and China Scholarship Council (grant 201606100058) (for HF). 相似文献46.
K M Fox M Richards A Jonathan J E Deanfield A P Selwyn 《International journal of cardiology》1983,3(3):315-327
This study was designed to determine if exercise testing using 16-lead precordial mapping can be used to identify patients with left main stem narrowing. In a group of 235 consecutive patients undergoing coronary angiography there were 35 patients with left main stem narrowing. The patients with left main stem disease differed from the others in that not only did they develop extensive S-T segment depression, but more specifically these changes occupied a characteristic position high on the precordium above the usual site of the precordial leads of the 12-lead electrocardiogram. This finding was then tested prospectively in a second group of 100 patients. Fourteen of the 100 patients had left main stem narrowing; the sensitivity and specificity of S- T segment changes high on the precordium in identifying patients with left main stem disease were 82 and 84% respectively. Thus precordial mapping and exercise testing is valuable in the diagnosis of patients with left main stem narrowing. The technique is simple and inexpensive and provides data not available using the conventional precordial leads of the 12-lead electrocardiogram. 相似文献
47.
John Yiannikas Jianis Marcomichelakis Peter Taggart Brian H. Kelly Richard Emanuel 《The American journal of cardiology》1981,47(2):238-243
Fifty asymptomatic men, 44 (88 percent) of whom were pilots or allied aviation personnel, were referred because of resting ST-T electrocardiographic changes indistinguishable from those of myocardial ischemia. Because of the nature of their occupations, cardiac catheterization was performed to establish the presence or absence of coronary artery disease. Exercise tests were performed and analyzed retrospectively with respect to exercise-induced changes in the S-T segment and R wave amplitude. The results were correlated with coronary angiographic and echocardiographic findings.The 50 subjects were classified into two groups: Group I, 5 men with angiographically proved coronary artery disease, and Group II, 45 men without significant coronary arterial obstruction. Analysis of the S-T segment changes at peak exercise showed 21 subjects (42 percent) with a positive exercise test and 29 (58 percent) with a negative test. All subjects in Group I had a positive test. Sixteen subjects (35 percent) in Group II had a false positive result. Analysis of exercise-induced changes in R wave amplitude revealed that six subjects had a positive R wave response on the basis of sum of the changes in voltage in the leads measured (Δ∑R). Four of the six subjects had coronary artery disease and the other two were thought to have a cardiomyopathy. One subject with coronary artery disease had a negative R wave response. Echocardiography revealed five subjects with asymmetric septal hypertrophy; two of these had a positive exercise test and three a negative test on the basis of S-T segment criteria.Thus, symptom-limited treadmill exercise testing of asymptomatic men with resting ST-T electrocardiographic changes produced a high incidence rate of false positive results when S-T segment criteria were used, whereas analysis of changes in R wave amplitude yielded only two false positive results, both in men who had evidence of other heart disease. 相似文献
48.
Over the past two decades, a number of Canadian paediatric academic programs, previously operated as separate hospitals, have been integrated into larger teaching hospitals or regional health authorities. The present article describes the recent experience of the Children’s Hospital of Western Ontario within the London Health Sciences Centre (London, Ontario) to illustrate the potential deleterious effects of planning, system and program changes in a large academic hospital without child health input at the executive decision-making level. The vision of the London Health Sciences Centre Executive Leadership Team and Board of Directors was divergent from that of the paediatric health care providers, which resulted in the resignation of a number of paediatric subspecialists and compromised the ability of the Department of Paediatrics to deliver paediatric care and educate future professionals. The present article highlights the need for the involvement of paediatric stakeholders in strategic planning in the hope that other academic centres can learn from this experience. 相似文献
49.
Vaccines are usually assessed by analyses of their safety and immunogenicity to determine the effectiveness of eliciting antibody responses against target organisms. However, it is equally important to establish antibody affinity because of its specific role in protection from infection. Antibody affinity can be determined by comparisons of various antibody concentrations in dose–response curves. During a study on the immunogenicity of a pentavalent vaccine in 888 infants, antibody affinity analyses of the hepatitis B and Haemophilus influenzae type b components were investigated in infants given 15 mg RE vitamin A with their vaccination and those who were not given vitamin A. In this paper we present the results of 222 infants; a 25% sub-sample of the original study. Analyses were carried out using dilutions of serum samples from fitted values corresponding to optical densities from antibody detection assays. These were obtained from the ligand binding equation and mid point titres in dose–response curves were then calculated. Vitamin A supplementation had no effect on the midpoint titres of Hepatitis B and H. influenzae type b vaccine derived antibodies. The significant effect of vitamin A supplementation on the Hepatitis B vaccine component observed in a previous seroprotection analysis is probably due to the amount of antibodies since affinity was unaffected. 相似文献
50.
The purpose of this study was to establish the relationship between fetal heart rate accelerations and fetal body movements in fetuses at 24 to 32 weeks' gestation. The results suggest that body movements in younger fetuses do not occur with accelerations that are readily recognizable (i.e., less than 15 bpm), but as fetuses get older, the interaction between body movements and fetal heart rate becomes more evident and accelerations become more recognizable (i.e., greater than or equal to 15 bpm). The data presented suggest that there is a maturational aspect to the relationship between fetal heart rate and fetal body movements as fetuses increase in gestational age from 24 to 32 weeks. The conclusion, therefore, is that the nonstress test, as presently defined for older fetuses, is not valid for gestations below 32 weeks, and new criteria must be established. 相似文献