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1.
【目的】 通过比较2019年获得“中国科技期刊卓越行动计划”领军期刊项目资助的期刊(以下简称“领军期刊”)与其对标期刊,探索我国科技期刊缩小与世界顶级期刊差距的对策,为我国一流科技期刊建设提供参考和借鉴。【方法】 利用Web of Science (WoS) 数据库和期刊官网,检索并总结领军期刊与其对标期刊的各项指标数据,分析领军期刊最近5年来的发展情况。【结果】 22种领军期刊的主要指标数据明显上升。2020年领军期刊共发表Article 和Review文章4025篇,比2019年的2630篇增长53.0%,2020年刊均载文量为183篇,比2019年的120篇增长53.0%;领军期刊总被引频次由2019年的99767 次大幅增长至2020年的153610次,增幅达54.0%;2020年领军期刊的平均被引半衰期为3.73年,而对标期刊的平均被引半衰期为9.35年。2020年,16种领军期刊跻身JCR学科排名前10%,10种领军期刊跻身JCR学科排名前5%。【结论】 领军期刊应构建良性的期刊发展生态、动态调整期刊的发展目标、紧扣国家战略和重大需求布局期刊发展方向、重视人才发展与储备、构建自主可控的国际传播平台与渠道,以完成引领行业发展的使命任务,实现可持续发展,从而带动我国期刊行业的整体发展与进步。 相似文献
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游潮 《中国现代神经疾病杂志》2021,(2)
自发性脑出血病死率和病残率较高,但缺乏有效的治疗策略。我国的脑出血相关研究与国际先进水平存在一定差距。近年国际上一系列临床研究从不同角度探讨脑出血的治疗方式,对我国脑出血研究和规范化治疗具有十分重要的参考价值。我国的脑出血临床治疗经验和研究成果要想走向世界,必须开展高质量的临床试验。四川大学华西医院神经外科正在开展INTERACT3试验,以及准备开展STICHⅢ试验,希望能够推动中国脑出血研究事业的进步。 相似文献
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BackgroundHeavy metal contamination has become a serious issue in this century especially detected in fish organs. Due to the presence of radioactive compounds in agricultural and sewage effluent, which destroys aquatic ecosystems, threatening human livelihoods. Health hazards associated with low and high consumption consumers assessed in five commercial fish species collected from Hurghada City, Egypt, during winter and summer, 2020. Atomic absorption spectrophotometer technique used for determination heavy meals in different organs and expressed as μg/g wet weight.ResultsHeavy metal concentrations in muscle ranged between:(0.054–0.109), (0.260–1.043), (0.264–0.897), (5.895–11.898), (0.381–0.970), (13.582–29.133) and (0.332–0.589) µg/g for Cd, Pb, Mn, Zn, Cu, Fe and Ni respectively, which were lower than those of gills and liver. These concentrations were within WHO, FAO/WHO, and EU standards. Consumption of edible species was lower than the (TDIs) established by the (JECFA) and Egyptian Standards. Even though THQ and TTHQ values were < 1 while, in children with highly consumer were> 1.ConclusionThis study concluded that intake of Red Sea fish is safe for human health. It is critical for consumers to be aware of the consequences of excessive fish consumption, particularly children with highly consumer, which represent possible health risks. 相似文献
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Malathi Murugesan Dilip Abraham Prasanna Samuel Sitara SR Ajjampur 《Indian journal of medical microbiology》2022,40(3):330-336
BackgroundCampylobacter spp. are one of the commonest causes of diarrhea in children under five and in resource poor settings also lead to malabsorption and stunting. The purpose of this systematic review was to understand the burden of Campylobacter spp. associated diarrhea among children in the South Asian countries.MethodsThis systematic review followed the PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analysis) guidelines. Databases were searched with defined keywords for publications from the years 1998–2018. Data on proportion of positive samples was extracted to compare the rates of Campylobacter infection among children (under the age of 19) from different study populations.ResultsOf the 359 publications screened, 27 eligible articles were included in this systematic review and categorized based on study design. In 8 case-control studies, Campylobacter spp. was detected more frequently among diarrheal cases (range, 3.2–17.4%) than non-diarrheal cases (0–13%). Although there were variations in the study population, overall, children under the age of two years experienced Campylobacter diarrhea more often than older children. Most studies reported stool culture as the method used to detect Campylobacter spp. however retesting using PCR-based methods significantly increased detection rates. Limited data were available on Campylobacter species. In 4 studies that provided species data, C. jejuni (3.2–11.2%) was shown to be the most common species, followed by C. coli.ConclusionIn South Asia, Campylobacter spp. are one of the most common bacterial diarrheal pathogens affecting children but there is a paucity of data on species, risk factors and attributable sources. Although a few studies were available, the epidemiology of campylobacteriosis remains uncertain. To understand the true burden and sources of infection, more detailed studies are needed collecting data from human, animal and environmental sources and using both culture and genomic tools. 相似文献
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Nanoparticles have found use in a wide range of applications, mainly as carriers of active biomolecules. It is thus necessary to assess their toxicity for human health, as well as for the environment, on which there is still a gap of knowledge. In this work, sea urchin Paracentrotus lividus, a widely used model for embryotoxicity and spermiotoxicity, has been used to assess potential detrimental effects of amino-functionalized mesoporous silica nanoparticles (NH2-MSiNPs) on embryonic development. Specifically, gametes quality, embryogenesis morphological and timing alterations, and cellular stress markers, such as mitochondrial functionality, were assessed in presence of different concentrations of NH2-MSiNPs in filtered seawater (FSW). Furthermore, dorsal-ventral axis development and skeletogenesis were characterized by microscopy imaging and gene expression analysis. NH2-MSiNPs determined a strong reduction in the egg fertilization rate. Consequently, the presence of NH2-MSiNPs resulted detrimental in P. lividus embryonic development, with severe morphological alterations correlated with an increased embryos mortality. Finally, NH2-MSiNPs treatment was responsible for other toxic effects, such as reduced mitochondrial function and skeletogenesis alterations, according to the reduced mineralization sites in the endoskeleton formation and the related genes altered expression. Taken together, these results suggest the potential toxic effects of NH2-MSiNPs on the marine ecosystem, with consequences for the development and reproduction of its organisms. Despite their promising potential as carriers of biomolecules, it is pivotal to consider that their uncontrolled use may result harmful to the environment and, consequently, to living organisms. 相似文献
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Li Sun Zia Sadique Isabel dos-Santos-Silva Li Yang Rosa Legood 《International journal of cancer. Journal international du cancer》2019,144(10):2596-2604
In low and middle-income countries mammographic breast cancer screening is prohibitively expensive and a cheaper alternative option is to use ultrasound as the primary screening test. In 2009, China launched a breast cancer screening programme for rural women aged 35–64 years with clinical breast examination coupled with ultrasound as the primary tool. Our study aimed to analyse the cost-effectiveness of breast screening compared to no screening among Chinese rural women. We developed a Markov model to estimate the lifetime costs and effects for rural women aged 35 years from a societal perspective. Asymptomatic women in the intervention arm were screened every 3 years before age 64 years. Breast cancer in the non-screening arm can only be diagnosed on presentation of symptoms. Parameter uncertainty was explored using one-way and probabilistic sensitivity analyses. Compared to no screening, breast cancer screening cost $186.7 more and led to a loss of 0.20 quality-adjusted life years (QALYs). Breast screening was more expensive and did harm to health among rural women with an incremental cost-effectiveness ratio (ICER) of $-916/QALY. The sensitivity analysis identified utility loss from false positives as the factor that most influenced the results, but this did not affect the conclusions. In a rural setting with such low breast cancer incidence, screening for asymptomatic disease is not cost-effective with current screening tools. Priority should be given to ensure that symptomatic women have proper access to diagnosis and treatment at an early stage as this will lead to mortality reductions without the usual screening harms. 相似文献
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