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Acute worsening heart failure (WHF) is seen in a sizable portion of patients hospitalized for heart failure, and is increasingly being recognized as an entity that is associated with an adverse in‐hospital course. WHF is generally defined as worsening heart failure symptoms and signs requiring an intensification of therapy, and is reported to be seen in anywhere from 5% to 42% of heart failure admissions. It is difficult to ascertain the exact epidemiology of WHF due to varying definitions used in the literature. Studies indicate that WHF cannot be precisely predicted on the basis of baseline variables assessed at the time of admission. Recent data suggest that some experimental therapies may reduce the risk of development of WHF among hospitalized heart failure patients, and this is associated with a reduction in risk of subsequent post‐discharge cardiovascular mortality. In this respect, WHF holds promise as a endpoint for acute heart failure clinical trials to better elucidate the benefit of targeted novel therapies. Better understanding of the pathophysiology and a consensus on the definition of WHF will further improve our epidemiological and clinical understanding of this entity.  相似文献   
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Thyrotropin (TSH) is the prime regulator of thyroid cell growth and function and acts through the thyrotropin receptor (TSHR) located on the surface membrane of thyrocytes. Somatic heterozygous mutations that cause TSHR activation in the absence of TSH have been found in toxic adenomas and in hot nodules of multinodular goiters. Clinically and histologically heterogeneous nodules can share common gain-of-function mutations. Mutation prevalence varies greatly and is inversely related to iodine intake of the population. We report a Greek patient presenting with subclinical hyperthyroidism due to a fast-growing autonomous hyperplastic nodule in a long-standing multinodular goiter. Direct DNA sequencing showed that the hot nodule harbored a somatic heterozygous activating TSHR mutation: substitution of glutamine for leucine in the third transmembrane helix. This mutation (L512Q) was recently described in two solitary toxic adenomas. This report expands the spectrum of mutations shared by dissimilar hot nodules, supporting a common mechanism for nonautoimmune thyroid autonomy. The identification of the L512Q substitution demonstrates that gain-of-function TSHR mutations are encountered in Greece, although iodine deficiency has been significantly corrected over the last three decades.  相似文献   
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The hyperfunctioning dopamine hypothesis in the mesocorticolimbic (MCL) system has been addressed by a neurogenetic approach in model systems. Thus, a morphometric analysis was carried out on neurons of origin of Substantia Nigra (SN) and Ventral Tegmental Area (VTA) dopamine systems of the Naples High-Excitability (NHE), Low-Excitability (NLE) and control lines. Male adult rats were tested in a spatial novelty for indices of activity and non-selective attention. Mesencephalic coronal sections were processed for tyrosine hydroxylase (TH) immunohistochemistry and cytochromoxidase (C.O.) histochemistry. Image analysis in the rostro-caudal plane showed (i) a higher neuron size of TH+ elements in the VTA of NHE and NLE, across the entire structure in the NHE, and only in the middle portion in the NLE; (ii) a higher expression of TH in the neuropil of the VTA in NHE; (iii) a lower C.O. activity in both NLE and NHE; (iv) no differences in the SN. The larger neuron size in both NHE and NLE rats as compared with control rats, along with higher TH expression mainly in the NHE, in absence of any relevant alteration in the SN, reveals an unbalance between the two dopamine systems and a subsequent alteration in limbic (reward, motivation, sustained attention) functions. The decreased C.O. activity might be due to reduced feedback inhibition by striatal GABA neurons and interneurons leading to increased DA neuron firing. In conclusion, the increased behavioral activity and impaired attention observed in the NHE rats are associated to hyperfunctioning MCL system in this genetic model of Attention-Deficit Hyperactivity Disorder (ADHD).  相似文献   
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This paper presents findings from a study of the context and processes of provider mergers in the NHS in England. Mergers are an example of organisational restructuring, a key lever for change in the UK health care sector and elsewhere, although it is only one strategy for organisational change. The framework for the study is key themes from the organisational change literature: the complexity of the effects of change; the importance of context; and the role of organisational culture. The drivers for health care mergers and the evidence for these are analysed. Using documentary analysis and in-depth qualitative interviews with internal and external stakeholders, the first part of the paper reports on stated and unstated drivers in nine mergers. This provides the context for four in-depth case studies of the process of merger in the second and third years post-merger. Our study shows that the contexts of mergers, including drivers of change, are important. Merger is a process without clear boundaries, and this study shows problems persisting into the third year post-merger. Loss of management control and focus led to delays in service developments. Difficulties in the merger process included perceived differences in organisational culture and perceptions of 'takeover' which limited sharing of 'good practice' across newly merged organisations. Merger policy was based on simplistic assumptions about processes of organisational change that do not take into account the dynamic relationship between the organisation and its context and between the organisation and individuals within it. Understanding the process of merger better should lead to a more cautious approach to the likely gains, provide understanding of the problems that are likely in the period of change, and anticipate and avoid harmful consequences.  相似文献   
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