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The “strong Black woman” construct has been well-documented in the United States as both an aspirational icon and a constricting burden for African-heritage women. It has not been examined among African-Canadians. Drawing on qualitative interviews and standardized measures with 50 African-heritage women in Eastern Canada, our analysis reveals their perceptions of the construct as both strongly endorsed as a source of cultural pride, yet also acknowledged to take a terrible toll on health and well-being. The construct arises from and directly benefits racism. It is imperative that health professionals understand the ways it shapes health and help-seeking behaviors.  相似文献   
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Abstract

Health and social care providers’ perceptions of Black-Canadian parent-youth sexual health communication has important implications for addressing knowledge gaps in the provision of services to young people and their parents. Providers’ perceptions are crucial as they often act as advisers in tailoring programmes or services to the perceived needs of parents and youth. To understand these perceptions, 17 semi-structured in-depth interviews were conducted with providers who worked with African, Caribbean or Black (ACB) parents and youth in Toronto, Ontario, Canada. Critical Race Theory was used to help guide the interpretation of findings. The findings revealed providers believed that many parents were unlikely to explicitly discuss sexual health or HIV prevention with young people. Additionally, providers perceived that the content of and approach to parent-youth sexual health communication differed between African and Caribbean clients. Moreover, providers believed that both parents’ and young people’s sex and gender impacted the quality, content and style of sexual health communication and had important implications for programme development. Overall, findings suggest a need for understanding the development of providers’ perceptions of this communication, ways to address these perceptions and further parent-provider collaboration to promote Black youths’ sexual health.  相似文献   
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Objectives

The purpose of this study was to review the institutional practice of surveillance transthoracic echocardiography (TTE) for diagnosing early prosthetic valve dysfunction (PVD).

Background

Bioprosthetic valve thrombosis (BPVT) is an important cause of PVD, and guidelines do not recommend routine TTE during the first 5 years after valve implantation.

Methods

The authors performed a retrospective case-control study of all suspected (imaging diagnosis) or confirmed (histopathological diagnosis) cases of BPVT from January 1997 through December 2016. Patients were matched 1:2 (age, sex, prosthesis position) to patients whose prostheses were explanted because of structural failure (SF). PVD was defined as a 50% increase above baseline gradient at valve implantation and classified as early (≤5 years) or late (>5 years) after implantation.

Results

There were 94 BPVT (51 suspected, 43 confirmed) and 188 SF cases; patient age 61 ± 9 years; men 61 (65%). The prosthesis positions were aortic 56%; mitral 26%; tricuspid 15%; and pulmonary 3%. Early PVD was more common in the BPVT versus SF group: 83 of 94 (88%) versus 20 of 188 (11%) (p < 0.001). Time from implantation to PVD was shorter for BPVT than SF: 26 months (interquartile range [IQR]: 12 to 43 months) versus 74 months (IQR: 48 to 102 months) (p < 0.001). At the initial PVD diagnosis, 81% of BPVT and 90% of SF patients were asymptomatic. However, BPVT patients had rapid symptomatic deterioration, requiring intervention sooner after PVD diagnosis: 6 months (IQR: 4 to 7 months) versus 51 months (IQR: 22 to 55 months) (p < 0.001).

Conclusions

Most patients with PVD due to BPVT were asymptomatic at initial diagnosis, which was made based on routine surveillance TTE, often performed before 5 years. BPVT, an acute disease process, requires timely diagnosis because patient conditions rapidly deteriorate. Further studies are needed to determine whether routine surveillance TTE should be considered for patients with bioprosthetic valves to identify pre-symptomatic features of BPVT in order to provide effective, appropriate therapy.  相似文献   
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Poly(phenylene ethynylene)‐alt‐poly(phenylene vinylene)s (PPE‐PPVs) with various thiophene units (thiophene, bithiophene, and 3,4‐ethylenedioxythiophene) at the X position, with the general backbone design (Ph? C?C? X ? C?C? Ph? CH?CH? Ph? CH?CH? ), bearing identical solubilizing side chains at the phenylene rings of the polymers, are synthesized to study the effect of this structural alteration on the properties such as the photophysics, the electrochemical properties, the charge‐carrier mobility, and the morphology of the materials and its impact on their photovoltaic performance. The polymers are obtained in good yields with reasonable molecular weights and show solubility in ordinary organic solvents required for solution‐processing applications. The polymer with a basic thiophene ring at the X positions shows the highest open‐circuit voltage (VOC of 930 mV) and the polymer with a bithiophene unit at the X position shows the highest short‐circuit current density and charge‐carrier mobility, whereas the polymer with 3,4‐ethylenedioxythiophene shows the lowest photovoltaic performance.

  相似文献   

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BackgroundAlthough there are robust data about the pathophysiology and prognostic implications of left ventricular (LV) systolic dysfunction in patients with acquired heart disease, similar prognostic data about LV systolic dysfunction are sparse in the tetralogy of Fallot (TOF) population. The purpose of this study was to perform a meta-analysis of all studies that assessed the relationship between LV ejection fraction (LVEF) and cardiovascular adverse events (CAEs) defined as death, aborted sudden death, or sustained ventricular tachycardia.MethodsWe used random-effects models to calculate hazard ratios (HRs) and 95% confidence intervals (CIs).ResultsOf the 1,809 citations, 7 studies with 2,854 patients (age 28 ± 4 years) were included. During 5.6 ± 3.4 years' follow-up, there were 82 deaths, 17 aborted sudden cardiac deaths, and 56 sustained ventricular tachycardia events. Overall, CAEs occurred in 5.1% (144 patients). As a continuous variable, LVEF was a predictor of CAE (HR 1.29, 95% CI, 1.09-1.53, P = 0.001) per 5% decrease in LVEF. Similarly, LVEF < 40% was also a predictor of CAE (HR 3.22, 95% CI, 2.16-4.80, P < 0.001).ConclusionsLV systolic dysfunction was an independent predictor of CAE, and we observed a 30% increase in the risk of CAE for every 5% decrease in LVEF, and a 3-fold increase in the risk of CAE in patients with LVEF <40% compared with other patients. These findings underscore the importance of incorporating LV systolic function in clinical risk stratification of patients with TOF and the need to explore new treatment options to address this problem.  相似文献   
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A survey of 25 hospitals in Nigeria has been conducted to assess the level of compliance to the Commission for European Communities (CEC) criteria for good radiographic practice in four adult radiographic examinations. Chest, skull, abdominal and lumbar spine radiographic examinations were assessed. Using a simple scoring system of ‘0’ for unfulfilled and ‘1’ for fulfilled criteria, the results show an average compliance level of 50 ± 8% for chest, 57 ± 8% for skull, 56 ± 10% for abdomen and 51 ± 7% for lumbar spine radiography. Findings show that the level of compliance could be corrected by the adoption of quality control programmes in the country.  相似文献   
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