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BackgroundThe effective management of patients with acute myocardial infarction (AMI) is time-dependent.ObjectivesTo assess the impacts of the implementation of prehospital care on admission rates and mortality associated with AMI.MethodsRetrospective, ecological study, which assessed data from the Brazilian Universal Health System, from all 853 municipalities of Minas Gerais, from 2008 to 2016. Excessive skewness of general and in-hospital mortality rates was smoothed using the empirical Bayes method. This study assessed the relationship between Mobile Emergency Care Service (SAMU) in each municipality and the following 3 outcomes: mortality rate due to AMI, AMI in-hospital mortality, and AMI hospitalization rate, using the Poisson hierarchical model. Rates were corrected by age structure and detrended by seasonality and temporal influences. A confidence interval of 95% was adopted.ResultsAMI mortality rates decreased throughout the study, on average 2% per year, with seasonal variation. AMI in-hospital mortality also showed a decreasing trend, from 13.81% in 2008 to 11.43% in 2016. SAMU implementation was associated with decreased AMI mortality (odds ratio [OR] = 0.967, 95% confidence interval [CI] 0.936 to 0.998) and AMI in-hospital mortality (OR = 0.914, 95% CI 0.845 to 0.986), with no relation with hospitalizations (OR = 1.003, 95% CI 0.927 to 1.083).ConclusionSAMU implementation was associated with a modest but significant decrease in AMI in-hospital mortality. This finding reinforces the key role of prehospital care in AMI care and the need for investments on this service to improve clinical outcomes in low- and middle-income countries.  相似文献   
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Hydrogen embrittlement causes deterioration of materials used in metal–hydrogen systems. Alloying is a good option for overcoming this issue. In the present work, first-principles calculations were performed to systematically study the effects of adding Ni on the stability, dissolution, trapping, and diffusion behaviour of interstitial/vacancy H atoms of pure V. The results of lattice dynamics and solution energy analyses showed that the V–Ni solid solutions are dynamically and thermodynamically stable, and adding Ni to pure V can reduce the structural stability of various VHx phases and enhance their resistance to H embrittlement. H atoms preferentially occupy the characteristic tetrahedral interstitial site (TIS) and the octahedral interstitial site (OIS), which are composed by different metal atoms, and rapidly diffuse along both the energetically favourable TIS → TIS and OIS → OIS paths. The trapping energy of monovacancy H atoms revealed that Ni addition could help minimise the H trapping ability of the vacancies and suppress the retention of H in V. Monovacancy defects block the diffusion of H atoms more than the interstitials, as determined from the calculated H-diffusion barrier energy data, whereas Ni doping contributes negligibly toward improving the H-diffusion coefficient.  相似文献   
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Lung transplantation has become in recent years a therapeutic option for infants with terminal lung disease with similar results to transplantation in adults. In Spain, since 1996 114 children lung transplants have been performed; this corresponds to 3.9% of the total transplant number. The most common indication in children is cystic fibrosis, which represents between 70-80% of the transplants performed in adolescents. In infants common indications are interstitial lung disease and pulmonary hypertension. In most children a sequential double lung transplant is performed, generally with the help of extracorpo-real circulation. Lung transplantation in children presents special challenges in monitoring and follow-up, especially in infants, given the difficulty in assessing lung function and performing transbronchial biopsies.There are some more specific complications in children like postransplant lymphoproliferative syndrome or a greater severity of respiratory virus infections. After lung transplantation children usually experiment a very important improvement in their quality of life. Eighty eight per cent of children have no limitations in their activity after 3 years of transplantation. According to the registry of the International Society for Heart & Lung Transplantation (ISHLT) survival at 5 years of transplantation is 54% and at 10 years is around 35%.  相似文献   
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Introduction

Organ refusal rates among Gypsies is much higher than that of any other social group in Spain. However, their attitude toward new therapies related to transplantation, such as the xenotransplantation, is not known. This is especially important in countries such as Spain, where there are research and development units for xenotransplantation.

Objective

To analyze the attitude toward xenotransplantation among the Gypsy population living in Spain.

Method

Type of study: Observational sociological study. Population under study: Adult Gypsy population currently residing in Spain. Sample: A random sampling of 230 adult Gypsies. Assessment instrument: A validated attitude questionnaire for xenotransplantation—PCID–XenoTx Ríos. Fieldwork: Random selection based on stratification. Anonymity and self-administered fulfillment. Statistics: Student t test, χ2, Fisher, and a logistic regression analysis.

Results

A sample of 206 Gypsies was obtained. Forty-five percent (n = 93) would accept a solid organ xenotransplantation if they needed it, and the results were similar to those currently obtained with human organs; 24% (n = 49) have doubts, and 31% (n = 64) would not accept the xenotransplantation. If the results were worse than with human organs, only 9% would accept the xenotransplantation (n = 19). Respondents with a favorable attitude toward xenotransplantation presented a more favorable attitude toward cadaveric organ donation (55% vs 34%, P = .01).

Conclusions

Gypsies do not present a very favorable attitude toward xenotransplantation, especially compared with other Spanish population groups. A favorable sensitivity is presented by the population group in favor of it to cadaveric organ donation, which could be used to sensitize this social group and promote donation campaigns with the aim of increasing donation rates.  相似文献   
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BackgroundCardiovascular diseases constitute an important group of causes of death in the country. Ischemic heart diseases that are the main causes of cardiopulmonary arrest, leading to an impact on the mortality of the cardiovascular diseases in the health system.ObjectiveAssess the number of home deaths by cardiopulmonary arrest notified by the Mobile Emergency Medical Service (SAMU) in March 2018, 2019 and 2020.MethodsObservational study carried out from the analysis of cardiopulmonary arrest mortality data of citizens assisted by SAMU in Belo Horizonte, Minas Gerais, Brazil. Social and clinical characteristics and occurrence information of the patients were analyzed. The mortality rate due to cardiopulmonary arrest in relation to the total number of attendances was assessed. A significance level of 95% was considered.ResultsThere was increase of home deaths due to cardiopulmonary arrest in March 2020 compared to March 2018 (p<0.001) and March 2019 (p=0.050). Of the deaths reported in 2020, 63.8% of the patients were aged 60 years or older, 63.7% of the occurrences were performed in the afternoon and approximately 87% of the cardiopulmonary arrest notified had associated clinical comorbidities, with systemic arterial hypertension and heart failure represented by 22.87% and 13.03% of the reported cases, respectively. The majority of the evaluated sample of this study did not have any medical care follow-up (88.7%).ConclusionConsidering the increase in the number of the deaths, we suggest reflections and readjustments regarding the monitoring of chronic non-transmissible diseases during a pandemic, as well as improvements in death surveillance. (Arq Bras Cardiol. 2021; 116(2):266-271)  相似文献   
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IntroductionThe autumn and winter bronchiolitis epidemics have virtually disappeared in the first year of the COVID-19 pandemic.Our objectives were characterised bronchiolitis during fourth quarter of 2020 and the role played by SARS-CoV-2.MethodsProspective multi-centre study performed in Madrid (Spain) between October and December 2020 including all children admitted with acute bronchiolitis. Clinical data were collected and multiplex PCR for respiratory viruses were performed.ResultsThirty-three patients were hospitalised with bronchiolitis during the study period: 28 corresponded to rhinovirus (RV), 4 to SARS-CoV-2, and 1 had both types of infection. SAR-CoV-2 bronchiolitis were comparable to RV bronchiolitis except for a shorter hospital stay. A significant decrease in the admission rate for bronchiolitis was found and no RSV was isolated.ConclusionSARS-CoV-2 infection rarely causes acute bronchiolitis and it is not associated with a severe clinical course. During COVID-19 pandemic period there was a marked decrease in bronchiolitis cases.  相似文献   
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