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1.
刘晓  张志常 《现代肿瘤医学》2019,(23):4169-4175
目的:分析2010年至2018年甲状腺结节相关SCI论文,并建模进行定性与定量分析。方法:利用文献计量学中的引文分析、共被引分析、数据可视化、聚类分析等方法,使用CiteSpace分析工具,分析来源于Web of ScienceTM核心合集数据库中有关论文的出版情况、国家、机构、作者、知识基础与研究热点。结果:到2018年10月31日截止,研究了4 618篇论文。发表论文数:美国在国家/地区中排名第一,延世大学在研究机构中排名第一,Kwak JY在所有作者中排名第一。从2010年开始,每年发表的论文数量都在稳步增长,有相当多的论文发表在如《新英格兰杂志》、《THYROID》、《JAMA》、《CELL》等高影响因子的期刊上。甲状腺结节的SCI论文参考文献聚类为6类,分别是papillary-like nuclear feature、current statu、radiofrequency ablation、ultrasound elastography、goiter area、data system。代表研究前沿的关键词是meta-analysis、recommendation、thyroid carcinoma、shear wave elastography与bethesda system。结论:本文通过对国际上甲状腺结节的研究基础、研究热点的分析,阐述了甲状腺结节的研究趋势,为我国医学工作者的研究提供参考。  相似文献   
2.
Background: While over half of stroke survivors recover the ability to walk without assistance, deficits persist in the performance of walking adaptations necessary for safe home and community mobility. One such adaptation is the ability to walk or step backward. Post-stroke rehabilitation rarely includes backward walking (BW) assessment and BW deficits have not been quantified in post-stroke community ambulators.

Objective: To quantify spatiotemporal and kinematic BW characteristics in post-stroke community ambulators and compare their performance to controls.

Methods: Individuals post-stroke (n = 15, 60.1 ± 12.9 years, forward speed: 1.13 ± 0.23 m/s) and healthy adults (n = 12, 61.2 ± 16.2 years, forward speed: 1.40 ± 0.13 m/s) performed forward walking (FW) and BW during a single session. Step characteristics and peak lower extremity joint angles were extracted using 3D motion analysis and analyzed with mixed-method ANOVAs (group, walking condition).

Results: The stroke group demonstrated greater reductions in speed, step length and cadence and a greater increase in double-support time during BW compared to FW (p < .01). Compared to FW, the post-stroke group demonstrated greater reductions in hip extension and knee flexion during BW (p < .05). The control group demonstrated decreased plantarflexion and increased dorsiflexion during BW, but these increases were attenuated in the post-stroke group (p < .05).

Conclusions: Assessment of BW can unmask post-stroke walking impairments not detected during typical FW. BW impairments may contribute to the mobility difficulties reported by adults post-stroke. Therefore, BW should be assessed when determining readiness for home and community ambulation.  相似文献   

3.
The country/region of origin of all original papers appearing in the International Journal of Psychiatry (IJGP) during the first 9 years of its publication was recorded. A more detailed analysis of citation patterns was carried out on the 105 original articles published during 1992. The results indicated that 50–60% of the articles emanated from the United Kingdom but that in general authors cited a broad range of specialities from journals published around the world. North American authors tended to cite North American sources more frequently than did their counterparts from other countries. There was evidence that the impact of the IJGP is increasing despite its omission from some scientific reference databases.  相似文献   
4.
2000~2004年《中华妇产科杂志》被引分析研究   总被引:1,自引:0,他引:1  
姜国成  明健 《医学信息》2006,19(5):794-797
目的 从文献引证的角度透视《中华妇产科杂志》的学术水平和期刊质量。方法依据《中国生物医学期刊引文数据库》(Chinese Medical Citation Indcx,CMCI),采用文献计量方法对《中华妇产科杂志》载文被CMCI来源期刊引用的情况进行统计分析及评价。结果 发文被引比例为55.21%,单篇论文平均被引次数为4.19次,被引作者群的地域分布30个省(直辖市)和国外,北京、广东和上海在妇产科研究领域居于前列。有559种期刊引用该刊,自引率为0.0512。结论 《中华妇产科杂志》所载文献质量较高,形成具有独立风格和特色且相对稳定的研究体系。该刊不仅是我国妇产科研究领域最重要的信息源之一,也是我国医学领域的主要核心期刊。  相似文献   
5.
Summary Retention of a backward classically conitioned reflex response was investigated in the spinal cat preparation. Facilitation of the flexion reflex was induced by the pairing of superficial peroneal nerve stimulation (30 Hz, 0.5 s), the US (unconditioned stimulus), with saphenous nerve stimulation (10 Hz, 1.5 s), the CS (conditioned stimulus). Both the US and CS were supramaximal for activation of A cutaneous afferent fibers. Experimental animals received 30 paired trials (US preceded CS by 0.25 s) with an intertrial interval (ITI) of three min. Control animals received the same stimuli but in an explicitly unpaired manner. Following acquisition, all animals received 30 additional CS-alone trials at five min intervals. This paradigm, which incorporated ITIs longer than those which had been used previously in backward conditioning studies, induced a long-lasting potentiation of the flexion reflex which appeared to be specific to spinal reflex pathways activated by A cutaneous fibers. The relevancy of these results to a more specific understanding of backward and forward classical conditioning in the spinal cat is discussed.Supported by NSF grants 8415917 and 8808495  相似文献   
6.
【目的】 检验引文归一化指标RCR与Scopus的FWCI指标及同行评议指标F1000之间的相关性,为引文归一化学科影响力评价实践提供理论支撑。【方法】 选取国际干细胞研究领域的学术论文为研究样本,采用正态性检验及相关性分析法研究论文的RCR指标、FWCI指标及F1000推荐次数、F1000评分之间的相关关系。【结果】 RCR指标与FWCI指标具有较强的相关性,而RCR指标与F1000推荐次数和F1000评分之间仅低度相关。【结论】 作为学科归一化指标,RCR与FWCI指标在论文影响力评价上具有一致性,但与同行评议指标F1000相关性较弱。未来,RCR指标在我国交叉学科期刊评价、建立我国科技期刊影响力评价基准、构建我国科技期刊动态评价系统方面具有较大借鉴意义。  相似文献   
7.
【目的】 提升英文科技期刊在国际同行评议中对于审稿专家审稿意见造假这一学术不端行为的防范意识和能力,进一步完善其对学术不端的防范举措。【方法】 针对英文科技期刊办刊实践中所发现的审稿专家批量捏造或制造审稿意见的现象,探析其外在存续条件与内在动机,阐述这类造假意见的主要表现形式,进而总结出发现和防范此类学术不端审稿专家的有效方式。【结果】 在国际同行评议中,审稿专家审稿意见造假的学术不端情况并非个例,所提出的方式可有效发现和防范此类审稿专家。【结论】 在国际同行评议中,英文科技期刊需要针对审稿专家审稿意见造假的情况,进一步完善学术不端防范措施。  相似文献   
8.
关于我院图书馆中外文期刊利用状况的调研   总被引:2,自引:0,他引:2  
目的 :明确图书馆专业期刊资源对科研活动的文献保障状况 ,初步制订出我馆的专业核心期刊表 ,以形成特色馆藏。方法 :应用流通统计法确定本馆的期刊文献利用情况 ,在此基础上 ,采用引文分析法确定我馆的核心期刊。结果 :本院研究生和教研人员引用文献的来源主要集中在 188种外文期刊和 69种中文期刊中 ,故这 188种外文期刊和 69种中文期刊可初步定为我馆的核心期刊。结论 :调研结果可作为图书馆确定藏书建设方向和特色的依据。  相似文献   
9.
1981~2000年《南通医学院学报》学术质量指标综合评价   总被引:3,自引:1,他引:2  
采用文献计量学方法对《南通医学院学报》20卷78期4713篇论文的多项学术质量指标进行统计分析。结果:(1)信息量指数0.55篇/页;(2)单元作者系数2.33人/篇;(3)论文合著率64.52%;(4)出版时滞8.5个月;(5)国家自然科学基金资助等省部以上课题论文86篇;(6)平均引文量4.81条/篇;(7)衰减系数41.6%,其中中文衰减系数54.6%,外文衰减系数33.4%。统计结果表明,信息量指数呈上升趋势,单元作者系数和论文合著率偏低,出版时滞改善显著,基金资助论文数所占,平均引文量偏少,衰减系数增长明显。  相似文献   
10.
BACKGROUND: Citation factors are applied to assess scientific work despite the fact that they were developed commercially in order to compare competing journals. The aim of the present study was to determine whether there is a relationship between citation factors and a trial's methodological quality using published randomised trials in lung cancer clinical research. Material and methods All of the randomised trials included in nine systematic reviews performed by the European Lung Cancer Working Party (ELCWP) were assessed using two quality scales (Chalmers and ELCWP). RESULTS: One hundred and eighty-one articles were eligible. The median overall ELCWP and Chalmers quality scores were 61.8% and 49.0%, respectively, with a correlation coefficient (r(s)) of 0.74 (P <0.001). A weak association was observed between citation factors and quality scores with the respective correlation coefficients ranging from 0.18 to 0.40 (ELCWP scale) and from 0.21 to 0.38 (Chalmers scale). American authors published trials significantly more often in journals with high citation factors than European or non-American authors (P <0.0001), despite no better methodological quality. Positive trials, which were significantly more likely to be published in journals with higher citation factors, were of no better quality than negative ones. CONCLUSION: Journals with higher citation factors do not appear to publish clinical trials with higher levels of methodological quality, at least for trials in the field of lung cancer research.  相似文献   
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