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61.
【目的】 在全球视野下,从宏观、中观、微观层面分析中国顶刊论文研究主题的特征及趋势。【方法】 基于1980—2020年NatureScience期刊上的研究型论文,利用对比分析法,从时间维度对我国顶刊论文不同层级的研究主题展开国际比较研究。【结果】 中国顶刊论文学科结构沿着与全球趋同的方向演进;中国顶刊论文覆盖的研究领域较少,一些增长型和衰减型研究领域呈现追随全球的显著趋势;中国顶刊论文研究主题多为追随型,起步晚、时滞长。【结论】 高水平研究的发展,不仅需要科研人员更加注重论文的内在质量,科技期刊也应充分发挥“把关人”作用,机构与国家应健全科研评价体系,为推动我国高水平研究提供良好的发展氛围与制度保障。  相似文献   
62.
科技进步与心血管病学的50年展望   总被引:5,自引:2,他引:3  
本文主要阐述未来50年心血管病学领域内的各种进步,包括基因诊断和治疗、心脏外科手术的发展等等.  相似文献   
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Kidney transplant (KT) outcomes for HIV-infected (HIV+) persons are excellent, yet acute rejection (AR) is common and optimal immunosuppressive regimens remain unclear. Early steroid withdrawal (ESW) is associated with AR in other populations, but its utilization and impact are unknown in HIV+ KT. Using SRTR, we identified 1225 HIV+ KT recipients between January 1, 2000, and December 31, 2017, without AR, graft failure, or mortality during KT admission, and compared those with ESW with those with steroid continuation (SC). We quantified associations between ESW and AR using multivariable logistic regression and interval-censored survival analysis, as well as with graft failure and mortality using Cox regression, adjusting for donor, recipient, and immunologic factors. ESW utilization was 20.4%, with more zero HLA mismatch (8% vs 4%), living donors (26% vs 20%), and lymphodepleting induction (64% vs 46%) compared to the SC group. ESW utilization varied widely across 129 centers, with less use at high- versus moderate-volume centers (6% vs 21%, P < .001). AR was more common with ESW by 1 year (18.4% vs 12.3%; aOR: 1.081.612.41, P = .04) and over the study period (aHR: 1.021.391.90, P = .03), without difference in death-censored graft failure (aHR 0.600.911.36, P = .33) or mortality (aHR: 0.751.151.77, P = .45). To reduce AR after HIV+ KT, tailoring of ESW utilization is reasonable.  相似文献   
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Kidney transplant program performance in the United States is commonly measured by posttransplant outcomes. Inclusion of pretransplant measures could provide a more comprehensive assessment of transplant program performance and necessary information for patient decision-making. In this study, we propose a new metric, the waitlisting rate, defined as the ratio of patients who are waitlisted in a center relative to the person-years referred for evaluation to a program. Furthermore, we standardize the waitlisting rate relative to the state average in Georgia, North Carolina, and South Carolina. The new metric was used as a proof-of-concept to assess transplant-program access compared to the existing transplant rate metric. The study cohorts were defined by linking 2017 United States Renal Data System (USRDS) data with transplant-program referral data from the Southeastern United States between January 1, 2012 and December 31, 2016. Waitlisting rate varied across the 9 Southeastern transplant programs, ranging from 10 to 22 events per 100 patient-years, whereas the program-specific waitlisting rate ratio ranged between 0.76 and 1.33. Program-specific waitlisting rate ratio was uncorrelated with the transplant rate ratio (r = −.15, 95% CI, −0.83 to 0.57). Findings warrant collection of national data on early transplant steps, such as referral, for a more comprehensive assessment of transplant program performance and pretransplant access.  相似文献   
69.
ObjectiveTo describe food-industry sponsorships of associations active in the field of childhood nutrition and obesity prevention in Spain in 2017-2018.MethodThe associations were located at https://www.google.es/ using the words “society”, “foundation” or “federation” in combination with the terms “nutrition”, “obesity”, “childhood”, “paediatrics” and “diabetes”. Sponsorship was defined as the declaration of funding received or the appearance of a food company logo on an association's website or in the programmes of its congresses or courses. The percentage of sponsored societies and its association with the existence of ethical codes was calculated using MS Excel.Results64% of the associations displayed some type of sponsorship, with this being most frequent among paediatric and nutrition societies, 83% and 80% respectively, and non-existent among public health societies. No association was found between the existence of an ethical code and sponsorship (odds ratio: 0.75; 95% confidence interval: 0.14-3.94). The leading corporate sponsors were Nestlé, Coca-Cola and Danone. Whereas the initiatives of sponsored societies were targeted at changing eating individual behaviours, those of unsponsored societies sought to promote changes in the food system and eating environments.ConclusionsFood industry sponsorship of foundations and scientific societies is very widespread in Spain, except among public health associations. Unlike sponsored associations, those unsponsored propose policies opposed by the food industry, which are aimed at improving the system and food and eating environments.  相似文献   
70.
《Vaccine》2021,39(44):6539-6544
BackgroundDeciding how best to invest in healthcare is never an easy task and prioritization is therefore an area of great interest for policymakers. Too low public vaccine confidence, which results in insufficient vaccine uptake, remains an area of concern for EU policy-makers. Within the European Joint action on vaccination, a work-package dedicated to research aims to define tools and methods for priority‐setting in the field of vaccination research. We therefore propose a prioritization framework to identify research priorities towards generating and synthesizing evidence to support policies and strategies aiming at increasing vaccine coverage.Materials/methodsWe used a multi-criteria decision analysis (MCDA) method inspired by the Child Health and Nutrition Research Initiative developed by Rudan et al. This quantitative methodology follows a series of steps involving different groups of experts and relevant stakeholders. The first step consists in identifying key research questions through a broad consultation. In parallel, a first group of experts is tasked to select criteria for prioritization of research questions, taking into consideration the ultimate goal of the exercise. Another group of experts is then requested to assess a weight to each of the criteria, using pair-wise comparisons. The final step consists in gathering experts who will assess each research question against the weighted criteria. This evaluation leads to assigning a score to each individual research question, which can then be ranked in order of priority.ResultsWe focused our work on four pre-selected pilot vaccines (pertussis, measles containing combination vaccines, influenza and HPV). The consultation generated 124 questions, which were secondarily sorted and re-worded to obtain 27 questions to be ranked. Criteria for setting priorities were the following: accessibility, answerability, deliverability, disease prevalence/incidence, effectiveness, equity, generalization, and territory. During a final face-to-face meeting international experts ranked the 27 questions and agreed on a consensual list of six top-priorities.ConclusionsWe have developed a transparent, evidence-based rigorous framework to defined key research questions to generate evidence towards the design of policies and strategies to increase vaccine coverage. Results were disseminated broadly and submitted to the EC for potential funding in the context of The Horizon Europe Program. The same process will be conducted in 2021 to identify vaccination research priorities regarding all vaccines used in the EU as well as COVID-19 vaccines.  相似文献   
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