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Bjoern Titz Karsta Luettich Patrice Leroy Stephanie Boue Gregory Vuillaume Terhi Vihervaara Kim Ekroos Florian Martin Manuel C. Peitsch Julia Hoeng 《International journal of molecular sciences》2016,17(9)
Smoking is a major risk factor for several diseases including chronic obstructive pulmonary disease (COPD). To better understand the systemic effects of cigarette smoke exposure and mild to moderate COPD—and to support future biomarker development—we profiled the serum lipidomes of healthy smokers, smokers with mild to moderate COPD (GOLD stages 1 and 2), former smokers, and never-smokers (n = 40 per group) (ClinicalTrials.gov registration: ). Serum lipidome profiling was conducted with untargeted and targeted mass spectrometry-based lipidomics. Guided by weighted lipid co-expression network analysis, we identified three main trends comparing smokers, especially those with COPD, with non-smokers: a general increase in glycero(phospho)lipids, including triglycerols; changes in fatty acid desaturation (decrease in ω-3 polyunsaturated fatty acids, and an increase in monounsaturated fatty acids); and an imbalance in eicosanoids (increase in 11,12- and 14,15-DHETs (dihydroxyeicosatrienoic acids), and a decrease in 9- and 13-HODEs (hydroxyoctadecadienoic acids)). The lipidome profiles supported classification of study subjects as smokers or non-smokers, but were not sufficient to distinguish between smokers with and without COPD. Overall, our study yielded further insights into the complex interplay between smoke exposure, lung disease, and systemic alterations in serum lipid profiles. NCT01780298相似文献
83.
Huan Luo Stephanie German Paal 《Computer-Aided Civil and Infrastructure Engineering》2019,34(11):935-950
Drift capacity of reinforced concrete (RC) columns is an important indicator to quantify the seismic vulnerability of RC frame buildings; however, it is challenging to accurately predict this value as the nonlinear behavior can vary greatly by column type. This article proposes a novel, local machine learning (ML) model, called locally weighted least squares support vector machines for regression (LWLS‐SVMR), which integrates LS‐SVMR and locally weighted training criteria to enhance and generalize the prediction of the drift capacity of RC columns, regardless of the type. A database of 160 circular RC columns covering flexure‐, shear‐, and flexure–shear‐critical specimens was developed to train and test the proposed LWLS‐SVMR. The proposed LWLS‐SVMR was validated by comparison with popular existing global and local learning approaches as well as a traditional empirical equation, and the results demonstrated that the proposed LWLS‐SVMR is superior to all other approaches and thus, is a promising artificial intelligence technique for enhancing the prediction of drift capacity, universally across RC flexure‐, shear‐, and flexure–shear‐critical columns. The LWLS‐SVMR exhibits capabilities which may yield it a feasible approach to predict complex, nonlinear behavior in a broad‐spectrum manner. 相似文献
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Blewitt Pamela; Rump Keiran M.; Shealy Stephanie E.; Cook Samantha A. 《Canadian Metallurgical Quarterly》2009,101(2):294
Shared book reading, and the conversation that accompanies it, can facilitate young children's vocabulary growth. To identify the features of extratextual questions that help 3-year-olds learn unfamiliar words during shared book reading, two experiments explored the impact of cognitive demand level, placement, and an approximation to scaffolding. Asking questions about target words improved children's comprehension and production of word–referent associations, and children with larger vocabularies learned more than children with smaller vocabularies. Neither the demand level nor placement of questions differentially affected word learning. However, an approximation to scaffolding, in which adults asked low demand questions when words first appeared and high demand questions later, did facilitate children's deeper understanding of word meanings as assessed with a definition task. These results are unique in experimentally demonstrating the value for word learning of shifting from less to more challenging input over time. Discussion focuses on why a scaffolding-like procedure improves children's acquisition of elaborated word meanings. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Poleshuck Ellen L.; Gamble Stephanie A.; Cort Natalie; Hoffman-King Debra; Cerrito Beth; Rosario-McCabe Luis A.; Giles Donna E. 《Canadian Metallurgical Quarterly》2010,41(4):312
Up to 37% of individuals experience chronic pain during their lifetimes. Approximately one fourth of primary care patients with chronic pain also meet criteria for major depression. Many of these individuals fail to receive psychotherapy or other treatment for their depression; moreover, when they do, physical pain is often not addressed directly. Women, socioeconomically disadvantaged individuals, African Americans, and Latinos all report higher rates of pain and depression compared with other groups. This article describes a version of interpersonal psychotherapy tailored for patients with comorbid depression and chronic pain, interpersonal psychotherapy for depression and pain (IPT-P). IPT-P potentially could be delivered to many patient populations in a range of clinical settings, but this article focuses on its delivery within primary care settings for socioeconomically disadvantaged women. Adaptations include a brief 8-session protocol that incorporates strategies for anticipating barriers to psychotherapy, accepting patients' conceptualization of their difficulties, encouraging patients to consider the impact of their pain on their roles and relationships, emphasizing self-care, incorporating pain management techniques, and flexible scheduling. In addition, IPT-P is designed as an adjunct to usual medical pain treatment, and seeks to engage non–treatment-seeking patients in psychotherapy by focusing on accessibility and relevance of the intervention to concerns common among patients with pain. Identifying patients with comorbid depression and chronic pain and offering IPT-P as a treatment option have the potential to improve clinical outcomes for individuals with depression and chronic pain. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Goodhew Stephanie C.; Visser Troy A. W.; Lipp Ottmar V.; Dux Paul E. 《Canadian Metallurgical Quarterly》2011,37(2):588
In object substitution masking (OSM) a sparse, temporally trailing 4-dot mask impairs target identification, even though it has different contours from, and does not spatially overlap with the target. Here, we demonstrate a previously unknown characteristic of OSM: Observers show reduced masking at prolonged (e.g., 640 ms) relative to intermediate mask durations (e.g., 240 ms). We propose that with prolonged exposure, the mask's visual representation is consolidated, which allows processing of the lingering target icon to be reinitiated, thereby improving performance. Our findings suggest that when the visual system is confronted with 2 temporally contiguous stimuli, although one may initially gain access to consciousness above the other, the “losing” stimulus is not irreversibly lost to awareness. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
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Evaluation of potential interfering agents on in vitro methods for the determination of the antioxidant capacity in anthocyanin extracts 下载免费PDF全文
Isadora R. N. de Oliveira Reinaldo F. Teófilo Eduardo B. de Oliveira Afonso M. Ramos Frederico A. R. de Barros Mariza de P. Maia Paulo C. Stringheta 《International Journal of Food Science & Technology》2017,52(2):511-518
The evaluation of the effects of sugars, metals, acids and other antioxidants on the in vitro antioxidant capacity of purified anthocyanin extract by different techniques was the purpose of this study. Three methods and the ways of expressing their results were evaluated: ABTSTEAC (capacity equivalent to Trolox, by ABTS (2,2′‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulphonic acid))), DPPHTEAC (capacity equivalent to Trolox, by DPPH (2,2‐diphenyl‐1‐picrylhydrazyl)), DPPHEC50 (50% reduction in the radical, by DPPH), DPPH%Sca (reduction in the scavenging capacity, by DPPH), FRAPTEAC (capacity equivalent to Trolox, by FRAP (reduction power of iron)) and FRAPEC50 (50% reduction in the radical, by FRAP). The way of expressing DPPH and FRAP results as EC50 showed the greater interfering extent, mainly when the medium contained tartaric and ascorbic acids. The most coherent method was ABTSTEAC in which only ascorbic acid interfered. Ascorbic acid was shown to interfere in all methods; thus, it must be removed prior to determining the in vitro antioxidant capacity of anthocyanins in food materials. 相似文献