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AIDS and Behavior - The World Health Organization identified men as an essential group to target with HIV testing and treatment strategies;: men who have sex with men (MSM) and male clients of...  相似文献   
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Systemic and coronary hemodynamic effects of prenalterol, a beta-1 receptor agonist, were determined in patients with chronic congestive heart failure, initially after intravenous administration (10 patients) and then after oral administration (eight patients). Cardiac index increased by 33 percent and 30 percent after intravenous and oral prenalterol, respectively. The increase in stroke volume index and stroke work index and decrease in pulmonary capillary wedge pressure and systemic vascular resistance were not significant. Myocardial oxygen consumption and coronary sinus blood flow increased in the majority of patients, although these changes were not statistically significant. There were no significant changes in transmyocardial norepinephrine or epinephrine balance. The systemic and coronary hemodynamic effects of both intravenous and oral prenalterol were similar. Major side effects included sudden death (two patients) and hypotension and bradycardia (three patients) during oral prenalterol treatment. It is concluded that improved left ventricular function following both intravenous and oral prenalterol may be associated with increased myocardial oxygen consumption, and serious adverse effects may occur during prenalterol therapy.  相似文献   
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The sensitivity and specificity of an enzyme-linked immunosorbent assay (ELISA), absolute numbers of T-helper cells, and T-helper: T-suppressor cell ratios were compared in asymptomatic controls and IgG Western blot-confirmed patients with the acquired immune deficiency syndrome (AIDS) in Kinshasa, Zaire, between August 1984 and May 1985. Two hundred sixteen (97.7%) of 221 IgG Western blot-positive AIDS patients and 4 of 97 (4%) controls were ELISA-positive, 3 of whom were Western blot-positive. The sensitivity and specificity of the ELISA was 97.7% and 99.0%, respectively, compared to Western blot results. Detection of the human immune deficiency virus using absolute number of T-helper cells (less than 400 cells/mm3) was as sensitive (98.2%), but less specific (90.7%). A T-helper: T-suppressor ratio of less than 0.9, had a sensitivity of 97.3%, and specificity of 94.8%. The ELISA test had the highest predictive value and greatest utility in an African clinical setting for detecting HIV infected patients where a wide range of other immunocompromising diseases are seen.  相似文献   
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Electrical and structural remodeling during the progression of cardiovascular disease is associated with adverse outcomes subjecting affected patients to overt heart failure (HF) and/or sudden death. Dysfunction in integral membrane protein trafficking has long been linked with maladaptive electrical remodeling. However, little is known regarding the molecular identity or function of these intracellular targeting pathways in the heart. Eps15 homology domain-containing (EHD) gene products (EHD1-4) are polypeptides linked with endosomal trafficking, membrane protein recycling, and lipid homeostasis in a wide variety of cell types. EHD3 was recently established as a critical mediator of membrane protein trafficking in the heart. Here, we investigate the potential link between EHD3 function and heart disease. Using four different HF models including ischemic rat heart, pressure overloaded mouse heart, chronic pacing-induced canine heart, and non-ischemic failing human myocardium we provide the first evidence that EHD3 levels are consistently increased in HF. Notably, the expression of the Na/Ca exchanger (NCX1), targeted by EHD3 in heart is similarly elevated in HF. Finally, we identify a molecular pathway for EHD3 regulation in heart failure downstream of reactive oxygen species and angiotensin II signaling. Together, our new data identify EHD3 as a previously unrecognized component of the cardiac remodeling pathway.  相似文献   
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Dentistry is rapidly entering a new era of evidence-based practice, and society is demanding prevention and treatment that has been proven to be effective in terms of meaningful health outcomes. Practitioners, individual patients and the public need randomized controlled trials because they provide the highest level of scientific evidence to change clinical practice and inform public health policy. Well-designed randomized controlled trials are conceptually simple but deceptively complex to design, implement and translate into clinical practice. Randomized controlled trials are fundamentally different from observational clinical research because they randomly assign volunteers to receive test or control interventions, they are prospective and the success of the test intervention is based on a meaningful clinical outcome that is specified before the trial begins. To be successful, randomized controlled trials must be carefully designed and powered to answer a specific question that will be generalizable to the population under study. Randomized controlled trials can be designed to evaluate efficacy, effectiveness, superiority, equivalence or noninferiority. Prominent issues and challenges in designing and conducting randomized controlled trials include carefully defining enrollment criteria, establishing an organizational infrastructure, use of a data-coordinating center, developing a manual of procedures, obtaining informed consent, recruiting and ensuring the safety of volunteer subjects, ensuring data quality, analysis and publication of trial outcomes, and translating results into clinical practice.  相似文献   
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The nature of the workplace continues to change as Europe adapts to the challenges of competing in a global marketplace. Across the European Union there is a trend of increasing absenteeism and early retirement due to mental health problems, particularly stress and depression. The social and economic costs of lost productivity in Europe are substantial. Moreover, the sustainability of social protection systems may be challenged further by increases in the levels of disability benefits paid to people who have left work on grounds of poor mental health. Yet despite these significant consequences, at both national and pan-European levels, decision-makers have been slow to recognise the importance of promoting mental health within the workplace, although recently there have been some positive developments. This paper outlines some of the socio-economic arguments for the promotion of good mental well-being in the labour force and identifies how they link with different national and European policy agendas around four key issues: economic growth and development, the promotion of a high level of public health, sustainability of social welfare systems and social inclusion. The role and activities to promote mental well-being in the workplace undertaken by both national and international organizations in Europe are outlined along with important gaps and challenges that need to be addressed.  相似文献   
70.
Magnetic resonance imaging (MRI)-only radiotherapy treatment planning is attractive since MRI provides superior soft tissue contrast without ionizing radiation compared with computed tomography (CT). However, it requires the generation of pseudo CT from MRI images for patient setup and dose calculation. Our machine-learning-based method to generate pseudo CT images has been shown to provide pseudo CT images with excellent image quality, while its dose calculation accuracy remains an open question. In this study, we aim to investigate the accuracy of dose calculation in brain frameless stereotactic radiosurgery (SRS) using pseudo CT images which are generated from MRI images using the machine learning-based method developed by our group. We retrospectively investigated a total of 19 treatment plans from 14 patients, each of whom has CT simulation and MRI images acquired during pretreatment. The dose distributions of the same treatment plans were calculated on original CT simulation images as ground truth, as well as on pseudo CT images generated from MRI images. Clinically-relevant DVH metrics and gamma analysis were extracted from both ground truth and pseudo CT results for comparison and evaluation. The side-by-side comparisons on image quality and dose distributions demonstrated very good agreement of image contrast and calculated dose between pseudo CT and original CT. The average differences in Dose-volume histogram (DVH) metrics for Planning target volume (PTVs) were less than 0.6%, and no differences in those for organs at risk at a significance level of 0.05. The average pass rate of gamma analysis was 99%. These quantitative results strongly indicate that the pseudo CT images created from MRI images using our proposed machine learning method are accurate enough to replace current CT simulation images for dose calculation in brain SRS treatment. This study also demonstrates the great potential for MRI to completely replace CT scans in the process of simulation and treatment planning.  相似文献   
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