首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   115篇
  免费   1篇
教育   29篇
科学研究   50篇
体育   24篇
文化理论   10篇
信息传播   3篇
  2022年   2篇
  2021年   5篇
  2020年   4篇
  2019年   4篇
  2018年   6篇
  2017年   3篇
  2016年   4篇
  2015年   9篇
  2014年   8篇
  2013年   27篇
  2012年   12篇
  2011年   8篇
  2010年   5篇
  2009年   3篇
  2008年   6篇
  2007年   1篇
  2006年   2篇
  2004年   1篇
  2003年   1篇
  2002年   2篇
  1999年   2篇
  1995年   1篇
排序方式: 共有116条查询结果,搜索用时 15 毫秒
71.
Black limestone samples from the quarries of Varenna (Lecco, I), Cene (Bergamo, I) and Riva di Solto (Bergamo, I) and widely used in Lombard architecture have been studied in terms of mineralogical, petrographic and chemical properties in order to provide a detailed characterisation and allow an unambiguous determination of their provenance. The inorganic and organic fractions have been separated from each other, and investigated using X-ray powder diffraction, atomic absorption, Hg-porosimetry, high performance liquid chromatography, gas chromatography, nuclear magnetic resonance and Fourier transform infrared spectroscopy. The occurrence of specific mineral phases, some binary chemical patterns (Fe/Mn, Zn/Sr, Zn/Co and Na/Cd) and the carbon chain relative molecular masses has proven to be useful markers to characterise unequivocally the materials studied.  相似文献   
72.
The timely diagnosis of acute coronary syndrome (ACS), in particular myocardial infarction (MI), is still one of the most challenging issues in medicine. The introduction into routine laboratory practice of assays for measuring the cardiospecific troponins has dramatically revolutionized the diagnostic approach and the recent development of methods with improved analytical sensibility (i.e., highly sensitivity [HS] assays), has further contributed to improve the negative predictive value of troponin testing but, contextually, has substantially lowered the clinical specificity of these markers. In particular, clinical studies have demonstrated the existence of an exercise-related increase of HS-troponins, with measurable values detectable in up to 94% of athletes undergoing endurance sports. This measurable amount oftroponin in blood would mirror an increased membrane permeability and early troponin release rather than reflecting a clinically threatening myocardial injury. As such, the measurable amount of cardiac troponins as assessed with the novel HS assays requires major clinical focus (i.e., serial measurement of cardiac biomarkers, detailed clinical history-taking, integration with ECG and imaging findings) to prevent misdiagnosis of ACS and/or MI in otherwise healthy persons.  相似文献   
73.
74.
Despite its widespread use in performance assessment, the reliability of vertical jump in an ageing population has not been addressed properly. The aim of the present study was to assess intra- and inter-day reliability of countermovement jump in healthy middle-aged (55-65 years) and older (66-75 years) men and women. Eighty-two participants were recruited and asked to perform countermovement jumps on two different occasions interspersed by 4 weeks. The middle-aged groups exhibited excellent absolute reliability for flight height, jump height, peak force, peak power, peak force/body mass, and peak power/body mass, with coefficients of variation ranging from 2.9% to 7.2% in men and from 3.6% to 6.9% in women and moderate-to-high intraclass correlations (0.75 to 0.97 in men; 0.77 to 0.95 in women). The older groups displayed good coefficients of variation (4.2% to 10.8% in men and 3.4% to 9.5% in women), but the intraclass correlations were low-to-high (0.43 to 0.84 in men; 0.42 to 0.93 in women). Overall, intra-session reliability was higher than inter-session reliability. Peak power was by far the most consistent variable, whereas flight and jump height had the most marked variability. The minimum detectable change varied from 10.5% to 33%, depending on the variable examined, suggesting important implications for intervention studies.  相似文献   
75.
A new device called Buzzy® has been recently presented that combines a cooling ice pack and a vibrating motor in order to relieve the venipuncture pain. The aim of this study was to evaluate the impact of Buzzy® use during diagnostic blood specimen collection by venipuncture for routine immunochemistry tests. Blood was collected from 100 volunteers by a single, expert phlebotomist. A vein was located on the left forearm without applying tourniquet, in order to prevent any interference from venous stasis, and blood samples were collected using a 20-G straight needle directly into 5 mL vacuum tubes with clot activator and gel separator. In sequence, external cold and vibration by Buzzy® was applied on the right forearm—5 cm above the chosen puncture site—for 1 min before venipuncture and continued until the end of the same procedure already done in the left forearm. The panel of tests included the following: glucose, total cholesterol, HDL-cholesterol, triglycerides, total protein, albumin, c-reactive protein, urea, creatinine, uric acid, alkaline phosphatase, amylase, AST, ALT, g-glutamyltransferase, lactate dehydrogenase, creatine kinase, total bilirubin, phosphorus, calcium, magnesium, iron, sodium, potassium, chloride, lipase, cortisol, insulin, thyroid-stimulating hormone, total triiodothyronine, free triiodothyronine, total thyroxine, free thyroxine and haemolysis index. Clinically significant differences between samples were found only for: total protein, albumin and transferrin. The Buzzy® can be used during diagnostic blood specimens collection by venipuncture for the majority of the routine immunochemistry tests. We only suggest avoiding this device during blood collection when protein, albumin and transferrin determinations should be performed.  相似文献   
76.
Exaptation, the cooption of existing technologies for emergent functions, is an important but neglected mechanism for innovation. Exaptation may enable an existing technology to (a) construct a new technological niche, (b) enter into a preexisting niche, or (c) transform the internal architecture of an artifact without changing its function.  相似文献   
77.
Abstract

Purpose: The aim of the paper is to analyse the attitude of Italian farms in gaining access to agricultural extension services (AES).

Design/methodology/approach: The ways Italian farms use AES are described through the AKAP (Awareness, Knowledge, Adoption, Product) sequence. This article investigated the AKAP sequence by submitting a questionnaire to a sample of Italian farms, providing questions on each step of the sequence.

Findings: The results confirm the validity of the model and the necessity to evaluate AES in each phase of the sequence, through an in-depth analysis of the possible motivation for not adopting them.

Practical implications: The functional repositioning of agriculture redefines the role of the farm, by introducing new possibilities of production and by fostering multifunctional activities. In this context, new tasks for AES emerge, aiming at sustaining farm development along either sectorial or territorial paths. Difficulties in adopting AES call for both fostering higher levels of access to services on behalf of farms and the adequate supply of services to farms' new needs.

Originality/value: AKAP models have been prevailingly used in developing countries to evaluate the efficacy of extension in increasing agricultural productivity. This article demonstrates how this model could be of help in developed agriculture too in performing new lines of development rooted in the new models of multifunctional agriculture.  相似文献   
78.
The transformative use of ICT (information and communication technology) in the educational setting is demanding continually assessing bottlenecks and conducive conditions with the aim of consolidating the pre-conditions and to dry the drawbacks from their root. As a result, this qualitative research approach employed to explore enablers and barriers of using ICT in initial teacher preparation in the context of JU (Jimma University), Ethiopia. The study employed in-depth interviews with student teachers and teacher educators. Participants' perception of ICT as a vehicle for quality learning and multiple access to ICT use pointed as supportive conditions. Whereas, mismatch of methodologies being used in teacher education and schools, resource constraints, marginalizing teacher education program, unsuccessful experience of learning via ICT, and lack of clear directive and expertise on the use of ICT were some of the major issues forwarded by the participants. Redesigning of the teacher education program in the way of using ICT is clearly indicated, the system that forces and reinforces the use of ICT in place is among the recommendations forwarded.  相似文献   
79.
Neuroanatomy is considered to be one of the most difficult anatomical subjects for students. To provide motivation and improve learning outcomes in this area, clinical cases and neurosurgical images from diffusion tensor imaging (DTI) tractographies produced using an intraoperative magnetic resonance imaging apparatus (MRI/DTI) were presented and discussed during integrated second‐year neuroanatomy, neuroradiology, and neurosurgery lectures over the 2008–2011 period. Anonymous questionnaires, evaluated according to the Likert scale, demonstrated that students appreciated this teaching procedure. Academic performance (examination grades for neuroanatomy) of the students who attended all integrated lectures of neuroanatomy, was slightly though significantly higher compared to that of students who attended these lectures only occasionally or not at all (P=0.04). Significantly better results were obtained during the national progress test (focusing on morphology) by students who attended the MRI/DTI‐assisted lectures, compared to those who did so only in part or not at all, compared to the average student participating in the national test. These results were obtained by students attending the second, third and, in particular, the fourth year (P≤0.0001) courses during the three academic years mentioned earlier. This integrated neuroanatomy model can positively direct students in the direction of their future professional careers without any extra expense to the university. In conclusion, interactive learning tools, such as lectures integrated with intraoperative MRI/DTI images, motivate students to study and enhance their neuroanatomy education. Anat Sci Educ 6: 294–306. © 2013 American Association of Anatomists.  相似文献   
80.

Introduction:

The phlebotomists’ procedures are a still source of laboratory variability. The aim of this study was to verify the efficacy of minor modification in procedure for collection of diagnostic blood specimens by venipuncture from CLSI H03-A6 document is able to reduce the tourniquet application time.

Materials and methods:

Thirty phlebotomists were invited to participate. Each phlebotomist was trained individually to perform the new venipuncture procedure that shortens the time of tourniquet release and removal. The phlebotomy training program was delivered over 8h. After training, all phlebotomists were monitored for 20 working days, to guarantee the adoption of the correct new procedures for collection of diagnostic blood specimens. After this time frame the phlebotomists were evaluated to verify whether the new procedure for blood collection derived from CLSI H03-A6 document was effective to improve the quality process by decrease in tourniquet application time. We compared the tourniquet application time and qualitative difference of phlebotomy procedures between laboratories before and after phlebotomy training.

Results:

The overall mean ± SD tourniquet application time before and after this intervention were 118 ± 1 s and 30 ± 1 s respectively. Minor modifications in procedure for blood collection were able to reduce significantly the tourniquet application time (−88 s, P < 0.001).

Conclusions:

The minor modifications in procedure for collection of diagnostic blood specimens by venipuncture from CLSI H03-A6 document were able to reduce the tourniquet application time. Now the proposed new procedure for collection of diagnostic blood specimens by venipuncture could be considered usefulness and should be put into practice by all quality laboratory managers and/or phlebotomy coordinators to avoid preanalytical errors regard venous stasis and guarantee patient safety.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号