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171.
The reconfigurable manufacturing system (RMS) is the next step in manufacturing, allowing the production of any quantity of highly customized and complex parts together with the benefits of mass production. In RMSs, parts are grouped into families, each of which requires a specific system configuration. Initially system is configured to produce the first family of parts. Once it is finished, the system will be reconfigured in order to produce the second family, and so forth. The effectiveness of a RMS depends on the formation of the optimum set of part families addressing various recon figurability issues. The aim of this work is to establish a methodology for grouping parts into families for effective working of RMS. The methodology carried out in two phases. In the first phase, the correlation matrix is used as similarity coefficient matrix. In the second phase, agglomerative hier archical Kmeans algorithm is used for the parts family for mation resulting in an optimum set of part families for reconfigurable manufacturing system. 相似文献
172.
Amita Gupta 《Journal of Early Childhood Teacher Education》2013,34(3):163-170
Abstract The author conducted a study with early childhood educators in New Delhi to understand the teachers’ perceptions of the relationship between their preparation and practice within a theory‐practice framework. The research problem emanated from the observations and experiences of the author, indicating an existing three‐way tension between the design of current Indian teacher education programs, the dominant discourse of early childhood education, and the underlying values of Indian philosophy that defined the construct of the teacher and child in Indian society. 相似文献
173.
This study delves into the motivations, symbolic rewards, and experiences of Filipinos involved in the creation of a magazine catering to the Filipino migrant workers’ community in Israel. Although practices of resistance are the prevailing framework within research about diasporic media, this paper offers another perspective of the construction of a subjugated minority's sphericule. Power (or lack thereof) is not necessarily a basic force of motivation. Participation in cultural production is not perceived as a journalistic endeavor by Filipinos, but a rare and crucial opportunity to be heard, to have a voice, to win over coerced living circumstances of alienation, solitude, and hard work. In this context they are not ‘just the caregiver,’ but accomplished writers, winners of competitions, and recipients of respect. Empowerment is derived from pleasure; it is grounded in recreational gratifications and a sense of mission that have no political dimensions. 相似文献
174.
Ram K. Gupta 《Journal of Experimental Education》2013,81(4):26-29
The purpose of this paper is to provide concrete illustrations of the efficacy of the multiple regression approach to the analysis of experimental results. A bridge between theoretical and specific applications is provided by parallel multiple regression and analysis of variance solutions for two typical educational designs. Detailed illustrations are given in the techniques of writing linear constraints and determining degrees of freedom. The major advantages of the multiple regression approach are its adaptability to unusual designs and the facilitation of meaningful interpretation afforded by the provision of regression weights in addition to the usual Fratios. 相似文献
175.
176.
AbstractThe aim of this study was to investigate the convergent and predictive validity of two skill tests that examine the ability of golfers to hit accurate approach-iron shots. Twenty-four high-level golfers (handicap = 2.6 ± 1.7) performed the Nine-Ball Skills Test (assesses the ability to shape/control ball trajectory with high accuracy) and the Approach-Iron Skill Test (assesses the ability to hit straight shots from varying distances with high accuracy). Participants then completed at least eight rounds of tournament golf over the following 90 days and reported an indicator of approach-iron accuracy (per cent error index). A moderate correlation (r = 0.50, P < 0.05) was noted between scores for both tests. Generalised estimating equations, using two covariates (lie of the ball and distance to hole), were used to determine model fit and the amount of variance explained for tournament per cent error index. Results showed that the Approach-Iron Skill Test was the slightly stronger predictor of on-course per cent error index. With both test scores considered together, a minimal amount of additional variance was explained. These findings suggest that either of the tests used individually or combined may be used to predict tournament approach iron performance in high-level golfers. 相似文献
177.
Dharamveer Yadav Sandhya Mishra Monika Gupta P. J. John Praveen Sharma 《Indian journal of clinical biochemistry : IJCB》2013,28(1):30-37
Reference intervals (RI) are the most common decision support tool used for interpretation of numerical laboratory reports. The quality of the RI can play as large a role in result interpretation as the quality of the result itself. As such there is hardly any study examining RI for liver specific biochemical parameters in Indian population especially north Indians having drastically different food habits as compared to rest of the India. So there is a need to establish the RI for north Indian population. Present study was conducted on 2,021 apparently healthy individuals of north Indian origin ranging in age from 15–60 years, were selected randomly using defined criteria. Lipemic, hemolysed, icteric and stored samples were also excluded adopting preanalytical criteria for rejection of sample. Non parametric methodology for determination of RI was adopted as most of the biochemical parameters included revealed non Gaussian distribution. Data were analyzed for middle 95 percentile (2.5th–97.5th percentile), median and 95 % confidence interval using SPSS software package version 10.0. The upper and the lower limit of RI (reported Vs observed) for bilirubin (0–1.2 Vs 0.30–1.30 mg/dL), serum glutamate oxaloacetate transferase (SGOT) (0–41 Vs 13–52.80 IU/L), serum glutamate pyruvate transferase (SGPT) (0–50 Vs 10–68 IU/L) showed wide variation as compared to reported standard RI however Gamma glutamyl transferase (GGT) (0–50 Vs 5.00–50.60 IU/L) remained within the reported standard RI. Further gender wise evaluation revealed higher cutoff in males (AST 14–55, ALT 11–70.35, GGT 6.76–51.09 in IU/L, bilirubin (0.40–1.34 mg/dL) as compared to females (SGOT 13–50.43, SGPT 9–63.43, GGT 3.92–48.70 in IU/L, Bilirubin 0.30–1.20 mg/dL) for both enzymatic and non enzymatic biochemical parameters. The variations may be attributed to dietary pattern smoking and alcoholism. 相似文献
178.
Ghizal Fatima Siddharth Kumar Das Abbas Ali Mahdi Nar Singh Verma Faizan Haider Khan Amit Mani Kumar Tiwari Tabrez Jafer Baby Anjum 《Indian journal of clinical biochemistry : IJCB》2013,28(2):181-184
Fibromyalgia syndrome (FMS) patients have disturbed sleep patterns which may lead to altered circadian rhythm in serum cortisol secretion. The aim of this study was to assess circadian changes, if any, in serum cortisol levels in female patients with FMS. Cortisol levels were estimated every 6 h during 24 h period; in 40 female patients satisfying ACR criteria for FMS (Age 36.4 ± 9.9), and 40 healthy females without FMS (Age 33.8 ± 11.1). A significant difference in the night time serum cortisol level was observed among the patients and control groups (patients, 12.9 ± 9.7 controls 5.8 ± 3.0; p < 0.01). However, no significant difference was found in serum cortisol levels in patients and control groups in the morning (patients, 28.4 ± 13.2 controls, 27.6 ± 14.5; p > 0.05), afternoon (patients, 14.4 ± 5.6 controls, 14.0 ± 6.6; p > 0.05) and evening hours (patients, 10.9 ± 5.8 controls, 8.9 ± 3.6; p > 0.05). It could be concluded that there is an abnormality in circadian secretion of cortisol in female FMS patients. 相似文献
179.
180.
Matthew B. Byrne Lisa Trump Amit V. Desai Lawrence B. Schook H. Rex Gaskins Paul J. A. Kenis 《Biomicrofluidics》2014,8(4)
Diffusion of
autocrine and paracrine signaling molecules allows cells to
communicate in the absence of physical contact. This chemical-based, long-range
communication serves crucial roles in tissue function, activation of the immune system,
and other physiological functions. Despite its importance, few in vitro
methods to study cell-cell signaling through paracrine factors are available today. Here,
we report the design and validation of a microfluidic platform that enables (i) soluble molecule-cell and/or
(ii) cell-cell paracrine signaling. In the microfluidic platform, multiple cell
populations can be introduced into parallel channels. The channels are separated by arrays
of posts allowing diffusion of paracrine molecules between cell
populations. A computational analysis was performed to aid design of the microfluidic platform.
Specifically, it revealed that channel spacing affects both spatial and temporal
distribution of signaling molecules, while the initial concentration of the signaling
molecule mainly affects the concentration of the signaling molecules excreted by the
cells. To validate the microfluidic platform, a model system composed of the
signaling molecule lipopolysaccharide, mouse macrophages, and engineered human embryonic
kidney
cells was introduced into the platform. Upon diffusion from the first
channel to the second channel, lipopolysaccharide activates the macrophages which begin to
produce TNF-α. The TNF-α diffuses from the second channel to the third channel to
stimulate the kidney
cells, which express green fluorescent protein (GFP) in response. By
increasing the initial lipopolysaccharide concentration an increase in fluorescent
response was recorded, demonstrating the ability to quantify intercellular communication
between 3D cellular constructs using the microfluidic platform reported
here. Overall, these studies provide a detailed analysis on how concentration of the
initial signaling molecules, spatiotemporal dynamics, and inter-channel spacing affect
intercellular
communication. 相似文献