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91.
Ka?an Huysal Yasemin U Budak 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2015,25(3):416-420
Introduction
Glycosylated hemoglobin (HbA1c) concentrations measured in clinical chemistry laboratories show large differences between their interlaboratory reported values. Laboratory measurements of quality performance should be based on quantitative data. The sigma metrics model provides an objective method for the assessment of current HbA1c assays and is useful in quality management planning. The aim of our study was to evaluate the analytical performance of the MQ-2000 PT HbA1c analyzer test results in the context of our operating conditions on the sigma scale.Materials and methods
The coefficient of variation was determined from the calculated mean and standard deviation evaluated from internal quality control (QC) (N = 168 days) (Shanghai Huachen Biological Reagent Co. Ltd, China) data, and records of external quality data (KBUDEK, İstanbul, Turkey) measured in the period from May to November 2013 were used to determine the bias. The resulting data and total allowable error rate (TEA = 10%) from the Clinical Laboratory Improvement Amendments of 1988 (CLIA’88) were used to calculate the sigma level.Results
The calculated coefficient of variations (CVs) at the two levels, normal (QC1 = 36.6 ± 2.38 mmol/mol) and pathological (QC2 = 84.7 ± 2.68 mmol/mol), were 6.5% and 3.1%, respectively. The average bias between the external QC and MQ-2000 PT during the study period was 4.3%. The calculated average sigma value was 1.19.Conclusions
The MQ-2000 PT HbA1c is a new analyser in the market; there is need for improvement and the method should be controlled with greater attention to ensure quality.Key words: diabetes mellitus, hemoglobin A1c protein, human, chromatography, high pressure liquid chromatography 相似文献92.
93.
How do pre-kindergarteners spend their time? Gender,ethnicity, and income as predictors of experiences in pre-kindergarten classrooms 总被引:2,自引:0,他引:2
Diane M. Early Iheoma U. Iruka Sharon Ritchie Oscar A. Barbarin Donna-Marie C. Winn Gisele M. Crawford Pamela M. Frome Richard M. Clifford Margaret Burchinal Carollee Howes Donna M. Bryant Robert C. Pianta 《Early childhood research quarterly》2010
The current paper considers how children spend their time in state-funded pre-kindergarten programs and how time use relates to ethnicity, gender, and family income, based on the assumption that how time is spent in pre-kindergarten is relevant for the programs’ success in narrowing achievement gaps. Classroom observations of 2061 children in 652 pre-k programs in 11 states were analyzed. Findings indicated that the pre-kindergarten day was roughly equally divided among free choice, teacher-assigned activities, and meals/routines. Children spent much of their time in language/literacy, social studies, and art, and less time in math and gross motor activities. Much of the pre-k day was spent in ‘no coded learning activity.’ Children in classes with lower proportions of Latino and African American children and higher average income-to-need ratios were generally engaged in richer and more stimulating experiences. The child-level variables of ethnicity and income were generally unrelated to how children spent their time, above and beyond the effects of classroom-level ethnicity and income. There were generally small, but significant gender differences – always in the gender-stereotyped direction – in how time was spent, especially during free choice time. 相似文献
94.
Mike U. Smith 《Science & Education》2010,19(6-8):539-571
This is the second of two articles that address recent scholarship about teaching and learning about evolution. This second review seeks to summarize this state of affairs and address the implications of this work for the classroom by addressing four basic questions: (1) What is evolution?/What components of the theory are important at the introductory level? (2) Why do students and members of the public at large need to understand evolution? (3) What makes evolution difficult to teach and learn? and (4) What promising instructional approaches have been developed and tested? The paper will also focus on concerns about both the research designs and the measures used in this work. Based on this review, I will then propose a set of pedagogical implications and recommendations for the classroom instructor and call for studies to address specific gaps identified. 相似文献
95.
周文英 《江西教育学院学报》1999,(2)
构建中国逻辑的横向体系,编写出教科书式的中国逻辑读本,是一项极具意义的学术工程。《提纲》乃这方面的闯新之作,计有“绪论”“概念”“辩说”“余论”四章。“概念”“辩说”叙说中国逻辑的两大支柱部分;“绪论”“余论”阐述中国逻辑的总体、总貌和特色 相似文献
96.
Ernest C. Davenport Mark L. Davison Pey‐Yan Liou Quintin U. Love 《Educational Measurement》2016,35(1):6-10
The main points of Sijtsma and Green and Yang in Educational Measurement: Issues and Practice (34, 4) are that reliability, internal consistency, and unidimensionality are distinct and that Cronbach's alpha may be problematic. Neither of these assertions are at odds with Davenport, Davison, Liou, and Love in the same issue. However, many authors in the testing community mention these terms not only together, but sometimes as if they are synonymous. Moreover, Cronbach's coefficient alpha is very popular as an index of reliability. Thus, articles discussing alpha are not only appropriate, but necessary. Our concerns are the same as formed the genesis of prior (2009) articles by these same authors, Sijtsma and Green and Yang. This rejoinder also makes comments about item parcels when tests are multidimensional and about factor analytic approaches to assessing reliability. 相似文献
97.
A. P. Jain A. Mohan O. P. Gupta U. N. Jajoo S. P. Kalantri L. M. Srivastava 《Indian journal of clinical biochemistry : IJCB》1998,13(2):119-122
In view of sufficient body of evidence to substantiate the role of free radical mediated oxidative injury in myocardial infarction
(M.I.), the utility of exogenous supplementation with antioxidant substance, vitamin E was studied. Forty patients of acute
myocardial infarction were divided into two equal groups, one who received vitamin E and the other who did not. Plasma MDA
levels showed a reduction in patients of M.I. who received vitamin E as well as in those who did not, however, the decrease
was significantly more in the vitamin E treated subgroup. 相似文献
98.
Cultural problems in minority education: Their interpretations and consequences—Part two: Case studies 总被引:1,自引:0,他引:1
Dr. John U. Ogbu 《The Urban Review》1995,27(4):271-297
Culture has featured prominently in minority educational research, policies, and intervention since the early 1960s. It is
receiving even more attention today in minority education discourse due to the emergence of cultural diversity and multicultural
education as popular national issues. A careful analysis of the new discourse suggests, however, that the issue has shifted
from how cultural differences enhance or deter the school adjustment and academic performance of minority children to the
problem of cultural hegemony and representation in school curriculum and other domains of education. In my two-part essay
I argue for a reconsideration of the earlier question about how culture affects minority school adjustment and academic performance.
In the first part of this essay l (1) argued that there are real cultural differences which confront minority children in
school and (2) proposed thecultural frame of reference as a conceptual tool to understand minorities' interpretations of and responses to the cultural problems they encounter.
More specifically, I suggested that voluntary minorities who interpret the cultural differences as barriers to be overcome
are more successful in crossing cultural boundaries. Involuntary minorities with an oppositional cultural frame of reference
are ambivalent in their interpretation of cultural differences as barriers and markers of group identity. They are less successful-in
crossing cultural boundaries. In this second part, I will demonstrate my explanations with two case studies: blacks, an involuntary
minority group and Chinese Americans, a voluntary minority group.
Part One of this paper appeared in Volume 27, Number 3, September 1995. 相似文献
99.
David M. Frost John B. Cronin Robert U. Newton 《Sports biomechanics / International Society of Biomechanics in Sports》2013,12(3):372-385
Explosive upper-body movements, with which the load is not thrown (non-ballistic), may comprise a phase during which forces are produced in opposition to the motion of the load. Thirty men completed three test sessions (free weight, ballistic, and pneumatic), each consisting of a one-repetition maximum (1-RM) and four explosive repetitions of a bench press at six loads (15, 30, 45, 60, 75, and 90% 1-RM). The end of the lifting phase for the non-ballistic conditions (free weight and pneumatic) was defined by: the point of peak barbell displacement and the point at which the vertical force became negative (positive work). When analysed by peak displacement, the ballistic condition elicited significantly greater mean velocity, force, and power at loads of 15–60% 1-RM compared with the free weight condition. When the period of negative work was removed, the mean free weight velocity, force, and power at loads below 60% 1-RM increased. Consequently, the only differences between the free weight and ballistic conditions were found at loads of 15% and 30% 1-RM. Including a period of negative work may underestimate all kinematic and kinetic variables dependent on the time to, or position of, the end of the lifting phase, for non-ballistic efforts. 相似文献
100.