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11.
Knowledge as a valuable asset of organizations is increasingly incorporated into thinking about strategy. Studies of knowledge management (KM) suggest that executives engaged in decision making often have a slender understanding of the strategic significance of knowledge. When addressing the challenge of explicating and designing a knowledge strategy, logics of codification and personalization have been differentiated and commended. The paper draws upon evidence from four case studies to identify factors that shape the evolving contexts of knowledge strategies. It is in these contexts that the challenge of continuously reviewing and revising the mix of codifying and personalizing aspects of strategic KM is practically accomplished. The cases are analysed with reference to external competition, leadership, organizational politics, culture and technology as a basis for advancing a more dynamic framework for the analysis of knowledge strategies.  相似文献   
12.
All currently avalable concrete creep predicting models cannot describe well the creep of a concrete structure because they all leave the effects of additives out of consideration. The purpose of this work was to modify model B3 for overcoming this deficiency. We tested thirteen specimens of C40 and C50 concrete with additives, out of which nine were for creep and four for shrinkage tests over a 700 d period under controlled temperature. We compared the experimental results for creep and shrinkage with those obtained by using model B3, and derived modification terms through regression analysis. Based on the experimental results of identical specimens under varied stress levels, we also derived a function considering the effect of stress level on creep. It is suggested that the creep prediction models without adjustment should not be used for modem concrete with a variety of additives.  相似文献   
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14.
Glycosylated Hemoglobin (GHb) was estimated using cation exchange resin binding method in 50 non diabetic healthy controls and 500 maturity onset diabetics. Percentage of glycosylated hemoglobin levels in controls was 7.27±0.456 (range 6.0–8.04) and 9.47±0.98 (range 8.2–13.63) in diabetic group. Glycosylated hemoglobin levels remain unaffected inspite of transient rise of serum glucose levels during an oral glucose tolerance test. Significantly elevated GHb A1. Furthermore significant elevation of GHb A1 was noticed in diabetics with all secondary complications suggesting poor glycemic control in these patients. The diabetics having retinopathy, nephropathy or diabetic foot had relatively higher GHb levels compared to patients having coronary artery disease or hypertension.  相似文献   
15.
Little is known of conditions which influence the stability of urinary enzymes upon storage in the bladder at 37°C. Using a continuous flow system simulatingin vivo conditions, we studied the influence of the pH of urine on the stability of two renal parenchymal enzymes N—Acetyl—β—D—Glucosaminidase (2—acetamido—2—deoxy—β—D—glucoside acetamidodeoxy glucohydrolase, NAG, EC 3.2.1.30) and L—Alanine aminopeptidase (Aminopeptidase N, AAP, EC 3.4.11.2). This continuous flow model that we have described can be employed to study the influence of pH on the stability of any renal enzyme excreted in urine. We also studied thein vitro effects of varying concentrations of low molecular weight regulatory metabolites such as urea, creatinine and uric acid and of some drugs excreted in urine, on the assay of these two enzymes. Urinary pH, urea content and some antibiotics seem to influence measured urinary NAG and AAP activities and we therefore express the need for caution before diagnostic interpretation of the urinary enzyme activities are made.  相似文献   
16.
Mathematical theories are essential for explanations in physics, chemistry andengineering. These theories often incorporate functions that are defined by theirrelation to other variables in the theory but not with reference to experimentalobservations. The wave function in quantum mechanics is perhaps one of thebest known example of such function, even though classical theories also providemany examples of such functions. These functions, which seem to hang in thin airdisconnected to experimental data, offer a daunting challenge to the instructor. Inthis article we consider the epistemic status of such functions and a method ofintroducing them to the students, a method that does not distort the original theory.We build our model for explanation on Hempel's analysis of relation between theoryand experiment and refine it further to show their roles in concept formation.  相似文献   
17.
We aimed to assess whether measuring carotid intima-media thickness (CIMT) and oxidative stress markers such as protein carbonyls, malondialdehyde, nitrate and glutathione in plasma of elderly patients without and with coronary artery disease (CAD) identifies early risk for CAD. A total of 50 cases with cardiovascular risk factors over the age of 60 years without CAD, and 50 patients with angiographically documented CAD over the age of 60 years were included in the study. Control group consists of 200 healthy individuals without the risk factors. Demographic details were obtained from all the subjects and CIMT measured by high frequency ultrasound and oxidative stress markers such protein carbonyls, malondialdehyde and total glutathione were determined in plasma by spectrophotometric methods. The distribution of cardiovascular risk factors in without CAD and CAD cases were smokers (16 vs 56 %), hypertension (26 vs 64 %), diabetes (16 vs 56 %) and dyslipidemia (18 vs 58 %) and positive family history (4 vs 38 %). None of the control group had any cardiovascular risk factors. Among the CAD cases, 16 % had single vessel disease, 44 % had double vessel disease and 40 % had triple vessel disease. The CIMT was significantly increased in CAD cases as compared to cases without CAD and healthy controls. On the other hand, CIMT was significantly increased in cases without CAD as compared to healthy controls. CIMT also increased with the duration of diabetes in patients without CAD and severity of disease in CAD cases. The levels of oxidants like plasma malondialdehyde, protein carbonyls, were significantly elevated and antioxidant glutathione levels and nitrate levels were significantly reduced in cases with and without CAD as compared to healthy controls. Oxidative stress markers and CIMT was found to be significantly increased in patients with cardiovascular risk factors like diabetes, family history of CAD, dyslipidemia, hypertension and smoking when compared to patients without risk factors. In patients with diabetes, CIMT increased as duration of disease increases and also in poorly controlled diabetes. In CAD group, when number of vessel involvement (severity of coronary disease) increases, the CIMT also increases confirming that CIMT is a quantifiable risk factor for CAD.  相似文献   
18.
The National Broadband Plan (NBP) recently announced by the Federal Communication Commission visualizes a significantly enhanced commitment to public computing centers (PCCs) as an element of the Commission's plans for promoting broadband availability. In parallel, the National Telecommunications and Information Administration (NTIA) has channelized part of the Broadband Technology Opportunities Program (BTOP) funding to PCCs. However, BTOP funding was the result of an unprecedented economic crisis, and is unlikely to be repeated. Future programs will need to evolve criteria for selecting projects for funding that maximize their cost-effectiveness. We argue in this paper that basing funding for PCCs on broadband availability (or non-availability), is not as cost-effective as considering a broader array of factors related to demand for internet access at public computer centers. We use data on public libraries from the National Center of Educational Statistics to identify factors predicting high demand for internet access at PCCs. Based on this analysis, we argue that low demand markets may benefit more from consumer outreach and digital literacy programs, than from infrastructure deployment. Also, we argue that markets with high availability, should receive more funding if there is high demand as well, as predicted by our model.  相似文献   
19.
EPR (Electron Paramagnetic Resonance) imaging is particularly useful in monitoring hypoxic zones in tumors which are highly resistant to radiation and chemotherapeutic treatment. This first part of the article covers aspects of CW (continuous wave) imaging with details of FT (pulsed Fourier Transform)-EPR imaging covered in Part 2, to be published in the next issue of Resonance.  相似文献   
20.
In this study, methodology and theory were linked to explicate the nature of education practice within schools facing exceptionally challenging circumstances (SFECC) in Trinidad and Tobago. The research design was an iterative quan>QUAL-quan>qual multi-method research programme, consisting of 3 independent projects linked together by overall purpose. Although large-scale quantitative data were first used to identify and describe SFECC, the overall programme was driven by an inductive theoretical thrust, with findings from the multiple-site case studies of Projects 2 and 3 used to construct substantive theory on SFECC. The integrated findings point to the pervasive role of beyond-school factors, which were magnified and intertwined with between- and within-school factors. SFECC in this study found great difficulty transcending states of chronic low performance. We hypothesized on the need for transformative school leadership, but in this context, greater external support by stakeholder agencies and broad place-based strategies appeared essential for turnaround.  相似文献   
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