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21.
The prognosis of Marfan syndrome in both adult and pediatric patients is primarily related to the cardiovascular complications. In infantile Marfan syndrome, although involvement of the mitral valve is the most frequently encountered cardiovascular lesion, the aortic root can be more worrisome because of its excessive dilatation, leading to aortic insufficiency or dissection. If the role of elective surgery is relatively well defined for adult patients, it is still debated during childhood. We report two patients, aged 22 months and 5 years, each presenting an aortic root aneurysm related to Marfan syndrome, and each treated with the Bentall procedure without specific age-related mortality or morbidity. These two patients experienced normal growth and were free of any complication for a follow-up period of 8 and 2 years, respectively. More than an absolute value of the aortic root dimension, it is the conjunction of the rate of progression of the aortic root dilatation, the degree and the duration of the aortic valve regurgitation, and its resulting left ventricular dysfunction that must be taken into consideration in choosing the surgical option.  相似文献   
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The aim of this article is to analyze the impact of the decentralization of the public national health system in Spain on citizens’ satisfaction with different dimensions of primary and hospital care. Using micro-data from the Health Barometer 1996–2009 and taking advantage of the exogeneity of the different pace of decentralization across Spain using a difference-in-differences strategy, we find that, in general, decentralization has not improved citizens’ satisfaction with different features of the health services. In our base model, we find that there are even some small negative effects on a subset of variables. Sensitivity analysis confirms that there is no empirical evidence for supporting that decentralization has had a positive impact on citizens’ satisfaction with health care. We outline several possible reasons for this.  相似文献   
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Dimethyl sulfoxide (DMSO) is an organic solvent with several biological applications. It is extensively used to dissolve compounds that hardly dissolve in water to detect their genotoxic activity in vitro. In this study DMSO will be tested to determine its genotoxic potential. The effect of DMSO on the frequency of chromosomal aberrations in anaphase as well as DNA fragmentation through the comet assay has been evaluated in the meristematic cells of the root tips of Vicia faba. It has been observed that the frequency of chromosomal aberrations increases when the concentration of DMSO increases, reaching its maximum value with 20% of DMSO and decreasing at 30 and 40% of DMSO, in comparison to this maximum value, but significantly higher than the values observed in the control. Similarly, the percentage of fragmentation and damage index evaluated through the comet assay showed the same behavior; some of the possible mechanisms of action are discussed.  相似文献   
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Even‐number, medium‐chain dicarboxylic acids (DAs), naturally occurring in higher plants, are a promising alternative energy substrate. Unlike the homologous fatty acids, DAs are soluble in water as salts. They are β‐oxidized, providing acetyl‐CoA and succinyl‐CoA, the latter being an intermediate of the tricarboxylic acid cycle. Sebacic acid and dodecanedioic acid, DAs with 10 and 12 carbon atoms respectively, provide 6.6 and 7.2 kcal g−1 each; therefore, their energy density is intermediate between glucose and fatty acids. Dicarboxylic acids have been proved to be safe in both experimental animals and humans, and their use has recently been proposed in diabetes. Studies in animals and humans with type 2 diabetes showed that oral administration of sebacic acid improved glycaemic control, probably by enhancing insulin sensitivity, and reduced hepatic gluconeogenesis and glucose output. Moreover, dodecanedioic acid intake reduced muscle fatigue during exercise in subjects with type 2 diabetes, suggesting an improvement of energy utilization and ‘metabolic flexibility’. In this article, we review the natural sources of DAs, their fate in animals and humans and their effect in improving glucose metabolism in type 2 diabetes.  相似文献   
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The epidemiological cycle of zoonotic phlebotomine‐borne Leishmania infantum is a complex system in which domestic animals and wildlife interact and participate in its maintenance and transmission. In this study, we combined entomological surveillance, xenomonitoring of L. infantum and identification of host feeding sources of engorged females to investigate the potential contribution of a periurban wildlife park to leishmaniosis in neighbouring residential areas. Overall, 7,309 sand flies were collected in 111 trap‐days during the summers of 2016–2018 in an endemic area in south‐east Spain. Five different sand fly species were captured, with Phlebotomus perniciosus, the main L. infantum vector in this region, representing the most common species. Sand fly distribution was spatially heterogeneous in terms of species, sexes and female physiological stage (unfed, gravid and engorged females) and related to host distribution and management, and environmental features. None of the 602 sand flies analysed for L. infantum infection by kinetoplast real‐time PCR were positive. We used molecular tools to identify the vertebrate hosts of sand flies and identified 17 host species, mainly mammals. Human DNA was not identified in engorged sand flies. This study provides evidence that wildlife parks in south‐east Spain are ideal grounds for sand fly vectors but do not necessarily increase L. infantum infection risk to humans and dogs living in surrounding residential areas. This is probably because vectors feed mostly on non‐L. infantum competent hosts and this should be investigated for a better understanding of the contribution of wildlife parks to the local epidemiology of L. infantum.  相似文献   
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Prenatal immune challenge (PIC) in pregnant rodents produces offspring with abnormalities in behavior, histology, and gene expression that are reminiscent of schizophrenia and autism. Based on this, the goal of this article was to review the main contributions of PIC models, especially the one using the viral-mimetic particle polyriboinosinic-polyribocytidylic acid (poly-I:C), to the understanding of the etiology, biological basis and treatment of schizophrenia. This systematic review consisted of a search of available web databases (PubMed, SciELO, LILACS, PsycINFO, and ISI Web of Knowledge) for original studies published in the last 10 years (May 2001 to October 2011) concerning animal models of PIC, focusing on those using poly-I:C. The results showed that the PIC model with poly-I:C is able to mimic the prodrome and both the positive and negative/cognitive dimensions of schizophrenia, depending on the specific gestation time window of the immune challenge. The model resembles the neurobiology and etiology of schizophrenia and has good predictive value. In conclusion, this model is a robust tool for the identification of novel molecular targets during prenatal life, adolescence and adulthood that might contribute to the development of preventive and/or treatment strategies (targeting specific symptoms, i.e., positive or negative/cognitive) for this devastating mental disorder, also presenting biosafety as compared to viral infection models. One limitation of this model is the incapacity to model the full spectrum of immune responses normally induced by viral exposure.  相似文献   
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