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191.
Tissue polypeptide specific antigen (TPS) measures an antigenic determinant associated with human cytokeratin 18. TPS is a marker of tumor cell activity in contrast to markers related to tumor burden. The value of detecting circulating TPS lies in the early detection of recurrence by serial determinations and in the rapid assessment of the efficacy of the treatment. Pretreatment levels of TPS in patients with metastatic breast cancer are related with prognosis. Decreasing TPS levels during therapy monitoring indicate response and a fast response is correlated to favourable prognosis. Increasing TPS levels, in the presence of clinically stable disease or partial remission, predict disease progression with a considerable lead-time. Improved effectiveness in breast cancer management can be seen when TPS is used in combination with CA 15-3. When tumor marker determinations are applied in a proper way in the appropriate situation, the results can assist the oncologist. Thus monitoring of therapy in patients with metastatic breast cancer should be based upon serial TPS and CA 15-3 determinations in serum. The use of tumor marker determinations in the early follow-up interval following surgery to detect early tumor recurrence may be simpler, more sensitive and less expensive than imaging methods.  相似文献   
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This paper reports the views and perceptions of around 1000 students in their final two years of compulsory schooling in respect of self-efficacy, goal orientation and motivation, stress and interpersonal skills. Gender differences are also reported. The study found that most students were generally positive about school and their future and felt in control of their lives. However, whilst male students felt better prepared in terms of problem solving, they were more likely to rely on luck and others to control their successes than were females. Whilst most pupils enjoyed going to school, over half often felt stressed, bored or fed up with school, and most of this group were female. The majority of students, of both sexes, felt comfortable approaching and communicating with teachers and adults in general, although up to a quarter had difficulties in this respect.  相似文献   
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We assessed the impact of expert students' instructional quality on the academic performance of novice students in 12th-grade physics classes organized in an expert model of cooperative learning (‘jigsaw classroom’). The instructional quality of 129 expert students was measured by a newly developed rating system. As expected, when aggregating across all four subtopics taught, regression analysis revealed that academic performance of novice students increases with the quality of expert students' instruction. The difficulty of subtopics, however, moderates this effect: higher instructional quality of more difficult subtopics did not lead to better academic performance of novice students. We interpret this finding in the light of Cognitive Load Theory. Demanding tasks cause high intrinsic cognitive load and hindered the novice students' learning.  相似文献   
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Objective

Comparison of global end-diastolic volume index (GEDVI) obtained by femoral and jugular transpulmonary thermodilution (TPTD) indicator injections using the EV1000/VolumnView® device (Edwards Lifesciences, Irvine, USA).

Methods

In an 87-year-old woman with hypovolemic shock and equipped with both jugular and femoral vein access and monitored with the EV1000/VolumeView® device, we recorded 10 datasets, each comprising duplicate TPTD via femoral access and duplicate TPTD (20 ml cold saline) via jugular access.

Results

Mean femoral GEDVI ((674.6±52.3) ml/m2) was significantly higher than jugular GEDVI ((552.3±69.7) ml/m2), with P=0.003. Bland-Altman analysis demonstrated a bias of (+122±61) ml/m2, limits of agreement of ?16 and +260 ml/m2, and a percentage error of 22%. Use of the correction-formula recently suggested for the PiCCO® device significantly reduced bias and percentage error. Similarly, mean values of parameters derived from GEDVI such as pulmonary vascular permeability index (PVPI; 1.244±0.101 vs. 1.522±0.139; P<0.001) and global ejection fraction (GEF; (24.7±1.6)% vs. (28.1±1.8)%; P<0.001) were significantly different in the case of femoral compared to jugular indicator injection. Furthermore, the mean cardiac index derived from femoral indicator injection ((4.50±0.36) L/(min·m2)) was significantly higher (P=0.02) than that derived from jugular indicator injection ((4.12±0.44) L/(min·m2)), resulting in a bias of (+0.38±0.37) L/(min·m2) and a percentage error of 19.4%.

Conclusions

Femoral access for indicator injection results in markedly altered values provided by the EV1000/VolumeView®, particularly for GEDVI, PVPI, and GEF.
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The call for reforms in science education has been ongoing for a century, with new movements and approaches continuously reshaping the identity and values of the discipline. The HPS movement has an equally long history and taken part in the debates defining its purpose and revising curriculum. Its limited success, however, is due not only to competition with alternative visions and paradigms (e.g. STS, multi-culturalism, constructivism, traditionalism) which deadlock implementation, and which have led to conflicting meanings of scientific literacy, but the inability to rise above the debate. At issue is a fundamental problem plaguing science education at the school level, one it shares with education in general. It is my contention that it requires a guiding “metatheory” of education that can appropriately distance itself from the dual dependencies of metatheories in psychology and the demands of socialization—especially as articulated in most common conceptions of scientific literacy tied to citizenship. I offer as a suggestion Egan’s cultural-linguistic theory as a metatheory to help resolve the impasse. I hope to make reformers familiar with his important ideas in general and more specifically, to show how they can complement HPS rationales and reinforce the work of those researchers who have emphasized the value of narrative in learning science. This will be elaborated in Part II of a supplemental paper to the present one. As a prerequisite to presenting Egan’s metatheory I first raise the issue of the need for a conceptual shift back to philosophy of education within the discipline, and thereto, on developing and demarcating true educational theories (essentially neglected since Hirst). In the same vein it is suggested a new research field should be opened with the express purpose of developing a discipline-specific “philosophy of science education” (largely neglected since Dewey) which could in addition serve to reinforce science education’s growing sense of academic autonomy and independence from socio-economic demands.  相似文献   
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