全文获取类型
收费全文 | 547篇 |
免费 | 36篇 |
专业分类
电工技术 | 7篇 |
化学工业 | 158篇 |
金属工艺 | 9篇 |
机械仪表 | 7篇 |
建筑科学 | 30篇 |
矿业工程 | 2篇 |
能源动力 | 12篇 |
轻工业 | 83篇 |
水利工程 | 4篇 |
无线电 | 31篇 |
一般工业技术 | 78篇 |
冶金工业 | 79篇 |
原子能技术 | 3篇 |
自动化技术 | 80篇 |
出版年
2024年 | 1篇 |
2023年 | 12篇 |
2022年 | 23篇 |
2021年 | 33篇 |
2020年 | 20篇 |
2019年 | 7篇 |
2018年 | 10篇 |
2017年 | 13篇 |
2016年 | 25篇 |
2015年 | 21篇 |
2014年 | 22篇 |
2013年 | 37篇 |
2012年 | 31篇 |
2011年 | 39篇 |
2010年 | 29篇 |
2009年 | 31篇 |
2008年 | 32篇 |
2007年 | 38篇 |
2006年 | 24篇 |
2005年 | 19篇 |
2004年 | 14篇 |
2003年 | 12篇 |
2002年 | 12篇 |
2001年 | 3篇 |
2000年 | 8篇 |
1999年 | 4篇 |
1998年 | 7篇 |
1997年 | 5篇 |
1996年 | 4篇 |
1995年 | 3篇 |
1994年 | 6篇 |
1993年 | 1篇 |
1992年 | 7篇 |
1991年 | 4篇 |
1990年 | 4篇 |
1989年 | 1篇 |
1988年 | 2篇 |
1987年 | 3篇 |
1986年 | 3篇 |
1985年 | 3篇 |
1984年 | 3篇 |
1983年 | 2篇 |
1981年 | 1篇 |
1978年 | 1篇 |
1977年 | 2篇 |
1970年 | 1篇 |
排序方式: 共有583条查询结果,搜索用时 0 毫秒
61.
Bednarz L. Rashmi Hackens B. Farhi G. Bayot V. Huynen I. 《Nanotechnology, IEEE Transactions on》2005,4(5):576-580
Room-temperature dc and broad-band high-frequency (HF) to dc conversion measurements of a double Y-branch junction (YBJ) are presented and discussed. Nonlinear dc characteristics of the devices at room temperature are observed and HF to dc conversion up to 40 GHz at room temperature is presented. The HF to dc conversion efficiency degradation is found to be partly due to losses in interconnects feeding the device. A small-signal equivalent circuit of the YBJ is proposed in order to verify the frequency dependence of intrinsic elements. 相似文献
62.
Nadine de Godoy Torso Marília Berlofa Visacri Julia Coelho Frana Quintanilha Maria Aparecida Cursino Eder de Carvalho Pincinato Patricia Moriel 《International journal of molecular sciences》2023,24(1)
Cisplatin is associated with dose-limiting nephrotoxicity, and the timely detection of acute kidney injury (AKI) can affect morbimortality. Therefore, this study aimed to investigate the tools for monitoring renal function in AKI. This was a retrospective, cohort study. Cisplatin-treated patients with head and neck cancer were included. Nephrotoxicity was assessed using serum creatinine, estimated creatinine clearance, serum electrolytic alterations, and plasma kidney injury molecule-1 (KIM-1). The toxicity severity was classified according to Common Terminology Criteria for Adverse Events (CTCAE), and AKI was classified by Risk, Injury, Failure, Loss, and End-stage kidney disease (RIFLE) and Acute Kidney Injury Network (AKIN). A total of 81 participants were included, of whom only 32 did not have AKI. Almost 90% of participants had a decreased estimated glomerular filtration rate five (D5) days after chemotherapy. The AKI estimate differs between AKIN and RIFLE; more participants were diagnosed by the RIFLE at D5, 19.5% versus 2.4% by AKIN, and fifteen had a discordance between these classifications. All laboratory markers showed significant changes on D5. KIM-1 appeared a possible biomarker when considering CTCAE or AKIN classifications (p < 0.05 on D5), but not when RIFLE classification was used (p = 0.0780). Further studies may seek to understand the profiles of different biomarkers together. 相似文献
63.
Naila Naz Syeda F. Naqvi Nadine Hohn Kiara Whelan Phoebe Littler Federico Roncaroli Andrew C. Robinson Jaleel A. Miyan 《International journal of molecular sciences》2023,24(1)
We investigated the cerebral folate system in post-mortem brains and matched cerebrospinal fluid (CSF) samples from subjects with definite Alzheimer’s disease (AD) (n = 21) and neuropathologically normal brains (n = 21) using immunohistochemistry, Western blot and dot blot. In AD the CSF showed a significant decrease in 10-formyl tetrahydrofolate dehydrogenase (FDH), a critical folate binding protein and enzyme in the CSF, as well as in the main folate transporter, folate receptor alpha (FRα) and folate. In tissue, we found a switch in the pathway of folate supply to the cerebral cortex in AD compared to neurologically normal brains. FRα switched from entry through FDH-positive astrocytes in normal, to entry through glial fibrillary acidic protein (GFAP)-positive astrocytes in the AD cortex. Moreover, this switch correlated with an apparent change in metabolic direction to hypermethylation of neurons in AD. Our data suggest that the reduction in FDH in CSF prohibits FRα-folate entry via FDH-positive astrocytes and promotes entry through the GFAP pathway directly to neurons for hypermethylation. This data may explain some of the cognitive decline not attributable to the loss of neurons alone and presents a target for potential treatment. 相似文献
64.
Anna Wong Nadine Marcus Paul Ayres Lee Smith Graham A. Cooper Fred Paas John Sweller 《Computers in human behavior》2009
Based on the assumption of a working memory processor devoted to human movement, cognitive load theory is used to explore some conditions under which animated instructions are hypothesised to be more effective for learning than equivalent static graphics. Using paper-folding tasks dealing with human movement, results from three experiments confirmed our hypothesis, indicating a superiority of animation over static graphics. These results are discussed in terms of a working memory processor that may be facilitated by our mirror-neuron system and may explain why animated instructional animations are superior to static graphics for cognitively based tasks that involve human movement. 相似文献
65.
Jonathan Dobres Nadine Chahine Bryan Reimer David Gould Bruce Mehler Joseph F. Coughlin 《Ergonomics》2016,59(10):1377-1391
Psychophysical research on text legibility has historically investigated factors such as size, colour and contrast, but there has been relatively little direct empirical evaluation of typographic design itself, particularly in the emerging context of glance reading. In the present study, participants performed a lexical decision task controlled by an adaptive staircase method. Two typefaces, a ‘humanist’ and ‘square grotesque’ style, were tested. Study I examined positive and negative polarities, while Study II examined two text sizes. Stimulus duration thresholds were sensitive to differences between typefaces, polarities and sizes. Typeface also interacted significantly with age, particularly for conditions with higher legibility thresholds. These results are consistent with previous research assessing the impact of the same typefaces on interface demand in a simulated driving environment. This simplified methodology of assessing legibility differences can be adapted to investigate a wide array of questions relevant to typographic and interface designs.
Practitioner Summary: A method is described for rapidly investigating relative legibility of different typographical features. Results indicate that during glance-like reading induced by the psychophysical technique and under the lighting conditions considered, humanist-style type is significantly more legible than a square grotesque style, and that black-on-white text is significantly more legible than white-on-black. 相似文献
66.
Sarah M. Kedziora Kristin Krker Lajos Mark Julia Binder Meryam Sugulle Martin Gauster Dominik N. Müller Ralf Dechend Nadine Haase Florian Herse 《International journal of molecular sciences》2021,22(7)
Preeclampsia (PE) is characterized by the onset of hypertension (≥140/90 mmHg) and presence of proteinuria (>300 mg/L/24 h urine) or other maternal organ dysfunctions. During human PE, renal injuries have been observed. Some studies suggest that women with PE diagnosis have an increased risk to develop renal diseases later in life. However, in human studies PE as a single cause of this development cannot be investigated. Here, we aimed to investigate the effect of PE on postpartum renal damage in an established transgenic PE rat model. Female rats harboring the human-angiotensinogen gene develop a preeclamptic phenotype after mating with male rats harboring the human-renin gene, but are normotensive before and after pregnancy. During pregnancy PE rats developed mild tubular and glomerular changes assessed by histologic analysis, increased gene expression of renal damage markers such as kidney injury marker 1 and connective-tissue growth factor, and albuminuria compared to female wild-type rats (WT). However, four weeks postpartum, most PE-related renal pathologies were absent, including albuminuria and elevated biomarker expression. Only mild enlargement of the glomerular tuft could be detected. Overall, the glomerular and tubular function were affected during pregnancy in the transgenic PE rat. However, almost all these pathologies observed during PE recovered postpartum. 相似文献
67.
Responds to D. Bruce's comments (see record 1998-00831-005) on N. Weidman's original article (see record 1995-00025-001) about the Lashley-Hull debate. The current article addresses the disagreements the author has with Bruce regarding their interpretations of the Lashley-Hull debate. These differences include what actually constituted "the debate," the extent to which the nature-nurture dichotomy was a feature of the debate, and the role of Watson's behaviorism in shaping Lashley's views. The article ends by noting a point on which both authors agree. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
68.
Leigh Irene W.; Smith I. Leon; Bebeau Muriel J.; Lichtenberg James W.; Nelson Paul D.; Portnoy Sanford; Rubin Nancy J.; Kaslow Nadine J. 《Canadian Metallurgical Quarterly》2007,38(5):463
This article describes characteristics of alternative assessment models deployed in the measurement of professional competencies across the professional life span based on the work of the American Psychological Association Task Force on the Assessment of Competence in Professional Psychology. Assessments of knowledge, decision making, performance and personal attributes, as well as integrated practice-based skills and tasks are described and compared on the basis of their validity, feasibility and practicality, fidelity, and relevance at difference stages of professional development. It is acknowledged that no single assessment can evaluate all competencies and that assessments can be combined in complementary ways. Assessments deployed in the nursing, dental, and medical professions are reviewed and contrasted with current practices in psychology. At the licensure level, differences in the assessments deployed among the 4 healthcare professions are described, and their candidate fees and number of candidates assessed annually are documented. Ideas for developing new assessments in psychology are discussed on the basis of the needs and financial resources available to psychology and the experiences of other healthcare professions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
69.
Paulhus Delroy L.; Harms P. D.; Bruce M. Nadine; Lysy Daria C. 《Canadian Metallurgical Quarterly》2003,84(4):890
Over-claiming is a concrete operalization of self-enhancement based on respondents' ratings of their knowledge of various persons, events, products, and so on. Because 20% of the items are nonexistent, responses can be analyzed with signal detection formulas to index both response bias (over-claiming) and accuracy (knowledge). Study 1 demonstrated convergence of over-claiming with alternative measures of self-enhancement but independence from cognitive ability. In Studies 2-3, the validity of the over-claiming index held even when respondents were (a) warned about the foils or (b) asked to fake good. Study 3 also showed the utility of the over-claiming index for diagnosing faking. In Study 4, the over-claiming technique was applied to the debate over the adaptive value of positive illusions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
70.
Attributional style and depressive symptoms among children. 总被引:1,自引:0,他引:1
Seligman Martin E. P.; Kaslow Nadine J.; Alloy Lauren B.; Peterson Christopher; Tanenbaum Richard L.; Abramson Lyn Y. 《Canadian Metallurgical Quarterly》1984,93(2):235
The reformulation of helplessness theory proposes that an insidious attributional style accompanies and predisposes depressive symptoms. The present study investigated predictions of the reformulation among 96 8–13 yr olds who completed the Children's Attributional Style Questionnaire (ASQ) and Children's Depression Inventory twice, 6 mo apart. 83 of their parents completed the adult ASQ and the Beck Depression Inventory at their children's 2nd testing. Children who attributed bad events to internal, stable, and global causes were more likely to report depressive symptoms than were children who attributed these events to external, unstable, and specific causes. This depressive attributional style predicted depressive symptoms 6 mo later, suggesting that it may be a risk factor for depression. Children's attributional style for bad events and their depressive symptoms converged with those of their mothers but not their fathers. (15 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献