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51.
Gian Luca Salvagno Elisa Danese Gabriel Lima-Oliveira Gian Cesare Guidi Giuseppe Lippi 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2013,23(2):201-205
Background
It is still uncertain whether or not avoidance to let disinfectant alcohol dry at the site of venipuncture is a source of spurious hemolysis when drawing venous blood.Methods:
In a consecutive series of 52 outpatients referred for routine laboratory testing, venous blood was drawn by direct venipuncture with (odd group) or without (pair group) wiping 70% isopropyl alcohol at the site of venipuncture. A 3.5 mL evacuated tube with clot activator and gel separator was drawn from a vein of the upper limb, serum was immediately separated with standard centrifugation and tested for potassium, lactate dehydrogenase (LD), aspartate aminotransferase (AST) and hemolysis index (HI) on Roche Cobas.Results:
No specimen was discarded for unsatisfactory venipuncture. No differences for age and gender were observed between groups. As regards the four parameters investigated, no significant differences could be observed between patients in whom blood was drawn with or without letting the alcohol dry. It is also noteworthy that no sample in both groups exceeded the conventional sample rejection threshold of cell-free hemoglobin.Conclusions:
The results of our prospective, randomized study attest that failure to wipe alcohol at the site of venipuncture should not be considered as a potential source of spurious hemolysis when drawing blood. 相似文献52.
Gabriel Lima-Oliveira Giuseppe Lippi Gian Luca Salvagno Martina Montagnana Geraldo Picheth Gian Cesare Guidi 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2013,23(2):218-223
Procedures involving phlebotomy are critical for obtaining diagnostic blood specimens and represent a well known and recognized problem, probably among the most important issues in laboratory medicine. The aim of this report is to show spurious hyperkalemia and hypocalcemia due to inadequate phlebotomy procedure. The diagnostic blood specimens were collected from a male outpatient 45 years old, with no clinical complaints. The tubes drawing order were as follows: i) clot activator and gel separator (serum vacuum tube), ii) K3EDTA, iii) a needleless blood gas dedicated-syringe with 80 I.U. lithium heparin, directly connected to the vacuum tube holder system. The laboratory testing results from serum vacuum tube and dedicated syringe were 4.8 and 8.5 mmol/L for potassium, 2.36 and 1.48 mmol/L for total calcium, respectively. Moreover 0.15 mmol/L of free calcium was observed in dedicated syringe. A new blood collection was performed without K3EDTA tube. Different results were found for potassium (4.7 and 4.5 mmol/L) and total calcium (2.37 and 2.38 mmol/L) from serum vacuum tube and dedicated syringe, respectively. Also free calcium showed different concentration (1.21 mmol/L) in this new sample when compared with the first blood specimen. Based on this case we do not encourage the laboratory managers training the phlebotomists to insert the dedicated syringes in needle-holder system at the end of all vacuum tubes. To avoid double vein puncture the dedicated syringe for free calcium determination should be inserted immediately after serum tubes before EDTA vacuum tubes. 相似文献
53.
The present study integrates two concepts: the notion of opinionleadership, as conceptualized and measured by the Strength ofPersonality (SP) scale, and the agenda-setting process. Thus,we suggest and test a two-step flow model in which certain individuals,the influentials, identify emerging issues in the mass mediaand then diffuse these issues to others via their personal networks.Based on a series of six national surveys conducted in Germany(1990) measuring issue salience and various personal characteristics,this study highlights the role certain individuals play in theemergence of the public agenda. The degree to which individualscan be influenced, measured by the SP scale, is found to bea powerful predictor of the formation of personal agendas, withhigh SP individuals differing from others in their identificationof emerging public issues. However, the analysis reveals thecomplexity of these relationships: they depend on the obtrusivenessof the issue, and they vary over time and location (East orWest Germany). The findings encourage the empirical pursuitof the suggested two-step flow model as appliedto the agenda-setting process. 相似文献
54.
Gabriel Jacobs & Catherine Rodgers 《British journal of educational technology : journal of the Council for Educational Technology》1997,28(4):292-304
This paper analyses the psychological, technical, administrative, organisational, institutional and general pedagogical problems encountered during Phase 1 (the trial phase) of a trans-European distance-learning project. Using basic-rate ISDN videoconferencing for remote interactive tutorials, Phase 1 involved the University of Wales Swansea and HEC Liège (Belgium), and provided practice in business English for Belgian students and business French for UK students of French and Business. The difficulties which have arisen during the phase have been many and varied, and not all could have been easily predicted from a review of the research literature. Solutions to some of them are suggested. 相似文献
55.
Two studies were carried out during university workshops, and analyzed the effects of resource interdependence on student‐student interactions, and the impact of these interactions on performance. Students worked cooperatively, either on complementary information (positive resource interdependence) or on identical information (resource independence). In Study 1, analysis of videotaped interactions revealed that working on complementary information produced more positive interactions; however this was not sufficient to prevent students who had no direct access to the information from being disadvantaged, because of informational dependence. In Study 2, with simpler texts allowing better information transmission, performance was favored when students worked on complementary information. Moreover, working on identical information not only enhanced confrontations of point of views, it also elicited competence threat. Further analysis revealed that competence threat mediated resource interdependence effect on performance. Discussion provides insights into the conditions in which different cooperative methods can benefit learning. 相似文献
56.
Extending Previous cG×I Findings on 5‐HTTLPR's Moderation of Intervention Effects on Adolescent Substance Misuse Initiation
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Gabriel L. Schlomer H. Harrington Cleveland Mark E. Feinberg Pedro S. A. Wolf Mark T. Greenberg Richard L. Spoth Cleve Redmond Eric P. Tricou David J. Vandenbergh 《Child development》2017,88(6):2001-2012
This study addresses replication in candidate gene × environment interaction (cG×E) research by investigating if the key findings from Brody, Beach, Philibert, Chen, and Murry (2009) can be detected using data (N = 1,809) from the PROSPER substance use preventive intervention delivery system. Parallel to Brody et al., this study tested the hypotheses that substance misuse initiation would increase faster from age 11 to age 14 and be higher at age 14 among: (a) 5‐HTTLPR short carrier adolescents versus long homozygotes, (b) control versus intervention adolescents, and (c) 5‐HTTLPR short carriers in the control condition versus all other participants. The hypotheses were generally supported and results were consistent with Brody et al.'s cG×I finding. Results are discussed in light of replication issues in cG×E research and implications for intervention. 相似文献
57.
Gabriel Diaz Maggioli 《通化师范学院学报》2007,(9):39-40
It is ironical that developments in the field of education call for teachers to differentiate instruction as a pre-requisite for effective learning,while teacher education and continuing professional development adhere to a one-size-fits-all philos- ophy. In general,professional development initiatives are part of'reform packages'with decisions about what,when,and 相似文献
58.
59.
Tom Gabriel 《International Journal of Educational Development》1983,3(3):305-311
Current development education in the United Kingdom usually offers participants from developing countries studies of what development is or should be. These programmes are well suited to the needs of higher-level planners or policy researchers. They contrast markedly with the urgent need for the knowledge of and skills in how to undertake planned economic and social changes. This paper suggests a possible route towards a practical, professional training for middle-and lower-level personnel engaged in managing development and extension services. Briefly, the paper notes the lack of educational programmes aimed at practical training and middle-level staff in Britain; and the role of education in the process of development. Current difficulties for locating these programmes in the developing countries themselves are discussed, and the outline for a suitably practical programme, initially based in Britain, is proposed. 相似文献
60.