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101.
G. V. Prosser 《Instructional Science》1978,7(4):359-383
Both active questions i.e. questions asked by subjects, and provided (or passive) questions i.e. offered to subjects as problems for solution, had been found to facilitate learning and retention of prose material when subjects were faced with a task of sufficient difficulty to challenge their competence. With difficult prose, boys and low ability subjects had gained most from active questions. These effects were more pronounced in the long term. In this study, the effects of relevant active questions i.e. questions which subjects can put alongside answers, are investigated and compared with those of active and provided questions, over a series of six presentations for both the short and the long term (i.e. after ten months). In the short term, although active questions give greater help than provided questions on the first presentation, and relevant active questions give the greatest improvement between the first and second presentations, provided questions are the most helpful overall. In the long term, however, both the active questions treatments prove to be as effective as provided questions. For low ability boys, the difference between treatments is negligble even in the short term; under the relevant active questions treatment the number of questions asked is greater; and the decline in inspection time over presentations is negligible.This study formed part of a Schools' Council Research project (Director: Dr. W. P. Robinson) in the Department of Psychology, University of Southampton. 相似文献
102.
V. Durand-Guerrier 《Educational Studies in Mathematics》2003,53(1):5-34
Implication is at the very heart of mathematical reasoning. As many authors have shown, pupils and students experience serious
difficulties in using it in a suitable manner. In this paper, we support the thesis that these difficulties are closely related
with the complexity of this notion. In order to study this complexity,we refer to Tarski's semantic truth theory,which contributes
to clarifying the different aspects of implication: propositional connective, logically valid conditional, generalized conditional,inference rules. We will show that for this purpose, it is necessary to extend the classical definition of implication as a relation between
propositions to a relation between open sentences with at least one free variable. This permits to become aware of the fact
that, in some cases, the truth-value of a given mathematical statement is not constrained by the situation, contrary to the
common standpoint that, in mathematics, a statement is either true or false. In the present paper, the didactic relevance
of this theoretical stance will be illustrated by an analysis of two problematic situations and the presentation of some experimental
results from our research on first-year university students' understanding of implication.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
103.
104.
Why do children learn in different ways: some are good students who show interest and zeal, while others are lazy and have to be taught against their will? Why do schools have over- and underachievers? Of course, there are a multitude of reasons. But almost 50 years ago it was shown using large data sets that families with high socioeconomic status are more likely to have children who are good students. Of course, there are many examples of successful students from poor families. However, they tend to be the exception to the rule. The certainty of success in school increases with rising socioeconomic status. 相似文献
105.
Yashika Gupta V. Mallika D. K. Srivastava 《Indian journal of clinical biochemistry : IJCB》2005,20(1):87-94
Platelets play a vital role in the progression of atherosclerosis and thrombosis, a major cause of death worldwide. Platelets
are activated by many triggers like elevated LDL in blood resulting in aggregation and formation of plaque. The purpose of
this study was to investigate the effect of LDL and signal transduction inhibitor on the activation of platelets in Ischaemic
risk subjects. Platelets from IHD and hyperlipidemic subjects were hypersensitive to ADP, as higher levels of platelet aggregation
were observed in these groups. LDL from IHD hyperlipidemic subjects was more effective in activating platelets from any other
group. Ox-LDL was more effective in activating platelets than native-LDL as monitored by level of platelet aggregation induced
by PAF and thrombin. Calcium channel blocker, nifedipine and verapamil inhibited platelet aggregation at micromolar level.
Protein kinase inhibitor, staurosporine was effective in inhibiting ADP induced aggregation at nanomolar level. 相似文献
106.
Urinary citric acid and calcium levels have been estimated in the urine of 20 normal healthy persons as well as 12 urinary
stone patients. Inhibition efficiency of these urine samples towards the mineralisation of urinary stone forming minerals,
viz., calcium phosphate, oxalate or carbonate, has been studied in an experimental model. Statistical correlation of the above
data has been made by computing the coefficient of determination and unexplained variance. Clinico-biochemical indexing of
calcium urolithiasis risk factor has been attempted in the light of the data. 相似文献
107.
108.
K. S. S. Saibaba P. V. L. N. Srinivasa Rao K. V. Dakshina Murty M. Vijaya Bhaskar 《Indian journal of clinical biochemistry : IJCB》1997,12(2):139-141
Selecting the correct method for routine analysis by ‘method evaluation’ is an important component of quality assurance. It
is a step-wise procedure that evaluates various analytical parameters like accuracy, precision etc of the given method. Finally
reference intervals are established for selected population. We evaluated an enzymatic method for serum creatinine. The results
show that it is an acceptable method based on the above mentioned criteria. 相似文献
109.
H.C. Reddy C.P. Reddy M.N.S. Swamy V. Ramachandran 《Journal of The Franklin Institute》1982,313(4):197-206
In this paper a method for the realization of RC transfer immittance functions with an unsymmetrical lattice is presented. The method yields minimal capacitor realizations for Z12(s) with no pole at s = 0 and ?y12(s) having no pole at s = ∞. The number of resistors needed are only two more than the minimum needed. 相似文献
110.
Lakshmi Lavanya Reddy Swarup A. V. Shah Alpa J. Dherai Chandrashekhar K. Ponde Tester F. Ashavaid 《Indian journal of clinical biochemistry : IJCB》2016,31(1):87-92
Acute coronary syndrome (ACS) is a term for a range of clinical signs and symptoms suggestive of myocardial ischemia. It results in functional and structural changes and ultimately releasing protein from injured cardiomyocytes. These cardiac markers play a major role in diagnosis and prognosis of ACS. This study aims to assess the efficacy of heart type fatty acid binding protein (h-FABP) as a marker for ACS along with the routinely used hs-TropT. In our observational study, plasma h-FABP (cut-off 6.32 ng/ml) and routinely done hs-Trop T (cutoff 0.1 and 0.014 ng/ml) were estimated by immunometric laboratory assays in 88 patients with acute chest pain. Based on the clinical and laboratory test findings the patients were grouped into ACS (n = 41) and non-ACS (n = 47). The diagnostic sensitivity, specificity, NPV, PPV and ROC curve at 95 % CI were determined. Sensitivity of hs-TropT (0.1 ng/ml), hs-TropT (0.014 ng/ml) and h-FABP were 53, 86 and 78 % respectively and specificity for the same were 98, 73 and 70 % respectively. Sensitivity, specificity and NPV calculated for a cut-off combination of hs-TropT 0.014 ng/ml and h-FABP was 100, 51 and 100 % respectively. These results were substantiated by ROC analysis. Measurement of plasma h-FABP and hs-TropT together on admission appears to be more precise predictor of ACS rather than either hs-Trop T or h-FABP. 相似文献