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1.
【目的】根据论文被引频次百分位创建不同学科论文被引频次基准线,探讨基于被引频次基准线遴选论文代表作的方法。【方法】以河南省科学技术领域学者为研究对象,以WoS数据库的学科分类为依据,建立不同学科论文被引频次基准线。依据该基准线对河南省各学科学者2009—2018年发表的每篇研究论文确定PR8分值,PR8分值≥3为论文代表作遴选的最低标准,其中PR8分值≥6者为第Ⅰ层次代表作,PR8分值≥5者为第Ⅱ层次代表作,PR8分值≥3者为第Ⅲ层次代表作。对不同层次代表作遴选的优秀学者进行比较。【结果】创建了177个学科论文被引频次基准线,根据代表作遴选标准确定了河南省学者7707篇代表作。采用代表作论文和全部论文以及采用不同层次代表作论文遴选优秀学者的结果明显不同。【结论】论文被引频次基准线在跨学科学术评价中具有重要意义,可以简单、明确地界定不同学科论文代表作;代表作评价制度的推行势在必行。  相似文献   
2.
The European Commission has established a Nanomaterials Repository that hosts industrially manufactured nanomaterials that are distributed world-wide for safety testing of nanomaterials. In a first instance these materials were tested in the OECD Testing Programme. They have then also been tested in several EU funded research projects. The JRC Repository of Nanomaterials has thus developed into serving the global scientific community active in the nanoEHS (regulatory) research. The unique Repository facility is a state-of-the-art installation that allows customised sub-sampling under the safest possible conditions, with traceable final sample vials distributed world-wide for research purposes. This paper describes the design of the Repository to perform a semi-automated subsampling procedure, offering high degree of flexibility and precision in the preparation of NM vials for customers, while guaranteeing the safety of the operators, and environmental protection. The JRC nanomaterials are representative for part of the world NMs market. Their wide use world-wide facilitates the generation of comparable and reliable experimental results and datasets in (regulatory) research by the scientific community, ultimately supporting the further development of the OECD regulatory test guidelines.  相似文献   
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Objectives

Use a task vehicle of sprint testing in wheelchair rugby (WCR) to explore the impact of small changes to test design using both group and individual analysis.

Design

Exploratory, repeated measures, on-court study

Method

25 national or international level wheelchair rugby players completed 5 × 5 m sprints under two conditions: (i) an acceleration from standstill in their own time, and (ii) an ‘active’ start, simulating a key aspect of performance. Video analysis and accelerometer data were used to measure key kinematic and performance variables with a focus on the first three strokes. Each player was grouped into a high-, mid-, or low-point group based on their sport-specific classification score. Group (paired sample t-tests) and individual (meaningful differences, performance coefficients, and Cohen’s d effect sizes) analysis assessed differences between the two conditions.

Results

The low-point classification group performed significantly slower in the active start (p < 0.05). There were no differences in sprint time for the high- and mid-point groups. Mid-point players achieved greater peak accelerations for strokes two and three in the active start (p < 0.05). Individual sprint performances varied substantially, ranging from 8% decrease to 14% increase in sprint time for the active start. Meaningful differences in peak accelerations were demonstrated for 23 out of the 25 players.

Conclusions

Small amendments to test design can lead to significant differences in individual athlete performance. Traditional group analyses masked important individual responses to testing conditions. There is need to further consider representative test design, and individual analysis for monitoring physical and skill performance.  相似文献   
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目的探讨大肠腺癌的临床、病理学特征及内镜对大肠腺癌的诊断意义。方法回顾分析182例经内镜检查诊断为大肠腺癌的临床资料及其病理诊断结果,分析内镜征象的病理基础。结果病理回报腺癌118例,黏液腺癌20例,印戒细胞癌15例,鳞癌17例,类癌6例,息肉6例。内镜对大肠腺癌诊断符合率为100%;镜下腺癌的主要征象对病理的诊断敏感性86.8%。结论内镜下腺癌的典型性征象对大肠腺癌的诊断敏感性较高。  相似文献   
7.
The development of a generic analytical method remains difficult when a high number of compounds has to be simultaneously considered. This study proposes an innovative strategy for the development of a solid phase extraction (SPE) procedure before liquid chromatography-mass spectrometry analysis of 34 diuretics and beta-blockers in urine samples. These compounds have been selected since they are often encountered in anti-doping control. The principle is based on the selection of representative analytes during SPE protocol optimization, allowing a drastic reduction of generated data and development time. To select the representative compounds, all substances were classified based on their SPE behavior with a generic method and groups were formed with the help of a chemometric tool, namely hierarchical cluster analysis (HCA). One representative analyte per group was selected and used for subsequent SPE method development. Once the SPE method was developed, compounds were analyzed by LC-MS and matrix effects were evaluated to determine the influence of the matrix on the SPE process and MS signal alteration due to endogenous compounds. As a result, matrix effects evaluation must be performed on all analytes; representative compounds previously selected for SPE development were unable to predict matrix effects.  相似文献   
8.
主要过敏原的物种分布及逐步聚类分析   总被引:2,自引:0,他引:2  
目的 综合分析数据库中过敏原的总体状况,在剖析重组过敏原研究领域的共性问题后,对主要过敏原进行聚类分析,为重组过敏原的深入研究指明方向。方法 以国际免疫学联合会过敏原命名分会公布的正式过敏原名录表为原始数据,对过敏原的物种分布特点进行分析,并采用Kolmogorov-Smironov检验对过敏原类型分布与相应的物种分布的一致性进行检验;针对氨基酸序列数据,采用ClustalW 1.83及MEGA2等生物信息学软件,辅之以手动缩减,对来自公共数据库中的主要过敏原进行逐步聚类分析,以获得代表性过敏原。结果 过敏原物种分布分析显示,510个过敏原归属于9大类共179个物种,不同类型过敏原所涉及的物种数及过敏原例数产生的两类分布相同;用关键词在蛋白质数据库中搜索得到的60条主要过敏原序列,聚类成有着明显差异的7个簇后,逐步聚类缩减到21个氨基酸序列无任何相关的代表性过敏原。结论 过敏原的研究是依所涉及的物种不同而逐步平行地展开,没有明显的物种或过敏原的侧重点;依据氨基酸序列的相似性,可以将不同物种来源的主要过敏原缩减到少数代表性过敏原上,从而减少重组过敏原的工作量。  相似文献   
9.
An efficiency calibration method has been developed to measure radioactivity of volume samples with HPGe detectors. The method has two main procedures. One is a point-source calibration at a representative point near the detector. The position of the representative point is determined by Monte Carlo simulations. The other is correction for absorption by a sample matrix and a sample container. This paper presents application of the method for obtaining efficiency curves for volume samples in the energy range from 22 to 1836 keV. In addition to the standard volume sources of cement and water matrices, measurement was made with some kinds of environmental samples that are often used in environmental monitoring for radiation control works. The composition of the environmental sample was determined by elemental analysis. For these samples, measured absorption correction factors were compared with those by the Monte Carlo simulations. As a result, detection efficiency curves were obtained with good accuracy for variety types of volume samples.  相似文献   
10.
In connection with two attempts on the lives of prominent politicians committed by mentally ill individuals during 1990 there occurred a marked increase in social distance towards the mentally ill among the German public. Even though the level of social distance subsided again during the 2 years following the attacks, it had not yet completely returned to its initial level by the end of 1992. The negative effects of these incidents on the attitude of the general public were able to be replicated on a regional level, after yet another violent attack by a mentally ill assailant in 1993, this time on the life of a famous female athlete.  相似文献   
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