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501.
Wei-Kai Liou Kaushal Kumar Bhagat Chun-Yen Chang 《Journal of Science Education and Technology》2016,25(3):460-473
The present study compares the highly interactive cloud-classroom (HIC) system with traditional methods of teaching materials science that utilize crystal structure picture or real crystal structure model, in order to examine its learning effectiveness across three dimensions: knowledge, comprehension and application. The aim of this study was to evaluate the (HIC) system, which incorporates augmented reality, virtual reality and cloud-classroom to teach basic materials science courses. The study followed a pretest–posttest quasi-experimental research design. A total of 92 students (aged 19–20 years), in a second-year undergraduate program, participated in this 18-week-long experiment. The students were divided into an experimental group and a control group. The experimental group (36 males and 10 females) was instructed utilizing the HIC system, while the control group (34 males and 12 females) was led through traditional teaching methods. Pretest, posttest, and delayed posttest scores were evaluated by multivariate analysis of covariance. The results indicated that participants in the experimental group who used the HIC system outperformed the control group, in the both posttest and delayed posttest, across three learning dimensions. Based on these results, the HIC system is recommended to be incorporated in formal materials science learning settings. 相似文献
502.
Hemanth Tumkur Lakshmikantha Naresh Kumar Ravichandran Mansik Jeon Jeehyun Kim Hyo-sang Park 《Journal of Zhejiang University. Science. B》2018,19(11):818-828
Objectives
The study was done to evaluate the efficacy of optical coherence tomography (OCT), to detect and analyze the microdamage occurring around the microimplant immediately following its placement, and to compare the findings with micro-computed tomography (μCT) images of the samples to validate the result of the present study.Methods
Microimplants were inserted into bovine bone samples. Images of the samples were obtained using OCT and μCT. Visual comparisons of the images were made to evaluate whether anatomical details and microdamage induced by microimplant insertion were accurately revealed by OCT.Results
The surface of the cortical bone with its anatomical variations is visualized on the OCT images. Microdamage occurring on the surface of the cortical bone around the microimplant can be appreciated in OCT images. The resulting OCT images were compared with the μCT images. A high correlation regarding the visualization of individual microcracks was observed. The depth penetration of OCT is limited when compared to μCT.Conclusions
OCT in the present study was able to generate high-resolution images of the microdamage occurring around the microimplant. Image quality at the surface of the cortical bone is above par when compared with μCT imaging, because of the inherent high contrast and high-resolution quality of OCT systems. Improvements in the imaging depth and development of intraoral sensors are vital for developing a real-time imaging system and integrating the system into orthodontic practice.503.
The increase in online graduate programs and the online mentoring of student research have led to the need to identify challenges faced by online mentees and successful strategies used by online mentors during the dissertation process. Based on semistructured interviews with ten graduates, strategies for online mentoring and areas of support valued by online doctoral students during the dissertation process are presented in this article. 相似文献
504.
Almerie MQ Matar HE Jones V Kumar A Wright J Wlostowska E Adams CE 《Health information and libraries journal》2007,24(4):283-286
Background: The Polish Medical Bibliography (Polska Bibliografia Lekarska) contains 350 000 records dating from 1979. These records from the fields of medicine, nursing, dentistry, health care systems and preclinical sciences are from nearly 300 biomedical journals published in Poland. Methods: We systematically searched the Polish Medical Bibliography Part II (1996–2006) CD‐ROM (July 2006) using both English and Polish phrases for randomized trials, manually checked results and, for the trials identified in this way, sought these on medline and embase . Results: Systematic searching identified records of 680 randomized trials from all areas of health care. Nearly 40% of these were not found on either medline or embase . Conclusions: The Polish Medical Bibliography should be of interest to health care information specialists concerned with comprehensive searches for trials. 相似文献
505.
We find that the presence of village Internet facilities, offering government to citizen services, is positively associated with the rate at which the villagers obtain some of these services. In a study of a rural Internet project in India, we identify a positive correlation for two such Internet services: obtaining birth certificates for children and applications for old age pensions. Both these government services are of considerable social and economic value to the citizens. Villagers report that the Internet based services saved them time, money, and effort compared with obtaining the services directly from the government office. We also find that these services can reduce corruption in the delivery of these services. After over one year of successful operation, however, the e-government program was not able to maintain the necessary level of local political and administrative support to remain institutionally viable. As government officers shifted from the region, or grew to find the program a threat, the e-government services faltered. We argue that this failure was due to a variety of Critical Failure Factors. We end with a simple sustainability failure model. In summary, we propose that the e-government program failed to be politically and institutionally sustainable due to people, management, cultural, and structural factors 相似文献
506.
Rahat Kumar Narinder Singh Kartar Singh Atul Kalhan K. K. Prasad 《Indian journal of clinical biochemistry : IJCB》2004,19(1):122-128
The normal coagulation process is initiated by disruption and exposure of the subendothelial components of blood vessels.
Platelets adhere to subendothelium-bound von Willebrand factor via glycoprotein (GP) Ib complex. This initial interaction
per se and the release of platelet agonists transduce signals that leads to the rise in intracellular Ca2+ which induces shape
change, prostaglandin synthesis, release of granular contents and conformational changes in platelet Gp IIb-IIIa. Gp IIb-IIIa
in activated platelets binds fibrinogen and other adhesive proteins and mediates platelet cohesion the primary haemostatic
plug. Furthermore, the activated platelets due to aggregation, result in the formation of fibrin (secondary hemostasis). Normally
the haemostatic process plays a delicate balance between keeping the blood in the fluid state to maintain flow and rapidly
forming an occluding plug following vessel injury. Thrombosis occurs because of alteration in this delicate balance. Arterial
thrombosis occurs in the setting of previous vessel wall injury mostly because of atherosclerosis, while venous thrombosis
occurs in areas of stasis. The recent advances in understanding of the haemostatic process have led to a better understanding
of the mechanism of action of many antithrombotic drugs and identification of new targets for drug development. The molecular
target of the ticlopidine has been identified. Large numbers of IIb-IIIa inhibitors have been developed. The mechanism of
action of heparin has been defined at the molecular level. As a result, a synthetic pentasaccharide, based on antithrombin-binding
domain of heparin, has been developed and tested successfully in clinical trials. New generation direct thrombin inhibitors
are being developed. Factor Xa has a critical position at the convergence of intrinsic and extrinsic pathway. The clinical
tolerability and the efficacy of low molecular weight heparins has established that inhibition of further thrombin generation,
by blocking factor Xa alone can be an effective way of preventing thrombus growth without inactivating thrombin. A large number
of specific factor Xa inhibitors are under development. Some of these are in preliminary clinical trials and appear to be
promising. Future clinical trials will determine whether these new drugs will provide better risk-benefit ratio in treatment
of thrombotic disorders. Similarly role of thrombolytics has been clearly established in many diseases including coronary
artery disease. 相似文献
507.
Ajai Kumar M. C. Pant H. N. Pandey J. L. Aggarwal R. S. Sharma L. D. Joshi S. Singh 《Indian journal of clinical biochemistry : IJCB》1993,8(1):47-50
Effect of feeding ripe and unripe papaya fruit pulps were investigated on blood lipid profile of normal male adult albino rabbits by giving them pulps separately at the dose of 15 and 30g per day along with standard diet over a period of six weeks. As compared to controls both fruit pulps resulted in highly significant (p<0.001) and consistent lowering of serum cholesterol, low density lipoprotein cholesterol and triglycerides and elevation in phospholipids and high density lipoprotein cholesterol levels at 1,3 and 6 weeks of fruit pulp feeding indicating a dose dependent effect. Observations clearly support medicinal value ofC. Papaya in the management of atherosclerosis, fatty liver, ischaemic changes and consequential myocardial infarction. 相似文献
508.
P. Pragathi P. V. Bharath Kumar P. Amar Kumar M. Ramakanth Reddy V. Sravani J. Neeraja Eapen Reeba Mary K. Gopalakrishna 《Indian journal of clinical biochemistry : IJCB》2005,20(2):195-197
Adenosine deaminase (ADA) and 5′-nucleotidase (5′-NT) activities were measured in sera of patients with ovarian cancer and
patients with benign ovarian tumour. The results were compared with that of a control group consisting of healthy women. ADA
levels were significantly increased (P<0.001) in the ovarian cancer group (n=50) but not in the benign group (n=28) when compared
to the controls (n=20). The results indicate that ADA and 5′-NT levels may help to differentiate malignant conditions from
benign tumours of the ovary in addition to the existing tests such as serum CA-125 levels and histopathological study. 相似文献
509.
510.
Kumar Laxman 《Instructional Science》2011,39(6):881-900
Solving real-world problems is an effective learning activity that promotes meaningful learning in formal educational settings.
Problems can be classified as being either well structured or ill structured. Internet information search approaches have
an influential role to play in the successful performance of problem solving. A better understanding of how students differentially
model information search strategies and movements in tackling well- and ill-structured problems is essential for creating
engaging problem-solving environments for students. Static measures, such as the number of accessed nodes or links, or the
number of times particular web browser function buttons are clicked, are limited in their ability to analyze attributes of
information search patterns. A more dynamic and spatial representation of web movements and navigational patterns can be realized
through the use of navigational paths as data. The two path-specific structural metrics that can be used to assess network-based
navigational paths in relation to the structuredness of the problem-solving task are compactness and stratum. These metrics are, respectively, the indicators of the connectedness and linearity of network-based structures defining students’ online navigational visitations during the problem-solving sessions. This
study explored the relevance and utility of these two metrics in analyzing the navigational movements of learners in seeking
out electronic information to accomplish successful problem solving. The outcome findings of this study show that well- and
ill-structured problems demand different cognitive and information seeking navigational approaches. The differing values of
the two path metrics in analyzing the search movements organized by students in attending to well- and ill-structured problems
were a direct result of the contrasting patterns of navigational path movements. The search patterns associated with well-structured
problem solving tended to be more linear and less connected, whereas those related to ill-structured problem solving were
more distributed and inter-connected. 相似文献