1,720,981 research outputs found
Gender and sex in the development and progression of renal diseases
Full text linkSex-based disparities in nephrology have been a historically understudied area.
In nephrology, gender differences exist with regard to the epidemiology, evolution and prognosis of chronic kidney disease (CKD). In some cases, these differences run contrary to the general population trends. We discuss such gender and sex disparities, including differing impact of traditional and novel risk factors, as well as hormonal factors, all of them potentially influencing propensity, progression and biochemical and psychological aspects of CKD. The factors involved in this gender disparity may include diet, kidney and glomerular size, differences in glomerular hemodynamics, and the direct effects of sex hormones.
The progression rate of many renal diseases is affected by sex. In polycystic kidney disease, membranous nephropathy, immunoglobulin A nephropathy, and “chronic renal disease of unknown etiology”, men progress at a faster rate to end-stage renal failure than women do. In many, but not all, animal models of renal disease, estrogens slow progression rate. Animal and experimental studies have tried to offer further mechanistic explanations for gender differences in disease progression. It has been suggested that the gender dimorphism of CKD progression may represent the effects of the interaction of circulating steroids with specific kidney receptors. Endogenous estrogens have in general been considered to have anti-fibrotic and anti-apoptotic effects on the kidney. On the other hand, the faster decline of kidney function in men has been attributed to the specific pro-apoptotic and pro-fibrotic properties of androgens
Chronic Renal Disease and Risk of Cardiovascular Morbidity-Mortality
No full textThe pathogenesis of cardiovascular disease in CKD differs subtly from that of non-CKD patients. As renal function declines, the role and impact of treating classical risk factors may change and diminish. However, hypertension, hypercholesterolaemia and smoking cessation management should be optimized and may require multiple agents and approaches, particularly as CKD advances. Hypertension treatment would appear to be one management area in which performance is less than ideal. Moreover there are mechanisms and risk factors that are specific to CKD, capable of triggering a vascular pathology and that justify the surplus of CV morbidity in CKD patients and that require we consider CKD as a CV risk factor per se. In the initial stages of CKD it would be advisable to implement all the preventative measures to stem the onset of CV disease, whereas in the more advanced stages a multifactorial approach is likely to be necessary, as we have learned from the STENO-study within the diabetes
Prevention of venous thromboembolism in hospitalized patients with chronic kidney disease
No full textDespite the high morbidity and mortality associated with venous thromboembolism in hospitalized medical patients with a number of risk factors, and large evidence that prophylaxis is effective, prophylaxis rates remain elusive in medically ill patients. Furthermore, in patients with renal failure, prophylaxis often is omitted or sub-optimal, due to fear of provoking hemorrhage. Patients with end-stage renal disease often have platelet deficits. Low molecular weight heparin (LMWH) therapy may also be difficult to manage in these cases because LMWH clearance is largely dependent on the kidneys. Administration of LMWH to patients with some degree of renal failure may lead to bioaccumulation of anti-Xa activity with an increased risk of bleeding. In recent years, LMWH has largely replaced unfractionated heparin (UFH) for the treatment and prophylaxis of thromboembolic disease. LMWHs have been shown to be superior to UFH in the prevention of venous thromboembolism. They are also easier to administer and do not require laboratory monitoring. However, several case reports and a metaanalysis indicate that the use of LMWHs at therapeutic doses in patients with advanced renal failure can be associated with major bleeding with serious adverse effects. In this paper, we review recent evidence supporting the safety of LMWHs at prophylactic doses in patients with mild or moderate renal disease. Current evidence suggests that bioaccumulation of enoxaparin (the most widely used LMWH) can occur when the drug is used at standard therapeutic doses in patients with severely impaired renal function. This risk can be reduced by empiric dose reduction or monitoring of anti-Xa heparin levels
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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