全文获取类型
收费全文 | 331篇 |
免费 | 15篇 |
专业分类
电工技术 | 1篇 |
化学工业 | 132篇 |
金属工艺 | 4篇 |
机械仪表 | 5篇 |
建筑科学 | 13篇 |
矿业工程 | 1篇 |
能源动力 | 5篇 |
轻工业 | 69篇 |
无线电 | 21篇 |
一般工业技术 | 20篇 |
冶金工业 | 6篇 |
原子能技术 | 1篇 |
自动化技术 | 68篇 |
出版年
2024年 | 1篇 |
2023年 | 5篇 |
2022年 | 32篇 |
2021年 | 42篇 |
2020年 | 7篇 |
2019年 | 9篇 |
2018年 | 7篇 |
2017年 | 3篇 |
2016年 | 12篇 |
2015年 | 7篇 |
2014年 | 12篇 |
2013年 | 16篇 |
2012年 | 15篇 |
2011年 | 24篇 |
2010年 | 18篇 |
2009年 | 26篇 |
2008年 | 19篇 |
2007年 | 10篇 |
2006年 | 16篇 |
2005年 | 16篇 |
2004年 | 6篇 |
2003年 | 8篇 |
2002年 | 6篇 |
2001年 | 4篇 |
1999年 | 1篇 |
1998年 | 2篇 |
1997年 | 7篇 |
1996年 | 3篇 |
1995年 | 1篇 |
1994年 | 2篇 |
1992年 | 1篇 |
1991年 | 2篇 |
1989年 | 1篇 |
1985年 | 1篇 |
1981年 | 1篇 |
1978年 | 1篇 |
1977年 | 1篇 |
1974年 | 1篇 |
排序方式: 共有346条查询结果,搜索用时 31 毫秒
81.
Tiziana Calamoneri 《Information Processing Letters》2013,113(10-11):361-364
82.
Luca Chiesa Sara Panseri Francesca Tiziana Cannizzo Bartolomeo Biolatti Sara Divari 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2016,33(7):1175-1189
The effects of long-term administration of low doses of dexamethasone (DX) and prednisolone (PL) on the metabolism of endogenous corticosteroids were investigated in veal calves. In addition to cortisol (F) and cortisone (E), whose interconversion is regulated by 11β-hydroxysteroid dehydrogenases (11βHSDs), special attention was paid to tetrahydrocortisol (THF), allo-tetrahydrocortisol (aTHF), tetrahydrocortisone (THE) and allo-tetrahydrocortisone (aTHE), which are produced from F and E by catalytic activity of 5α and 5β-reductases. A specifically developed HPLC-ESI-MS/MS method achieved the complete chromatographic separation of two pairs of diastereoisomers (THF/aTHF and THE/aTHE), which, with appropriate mass fragmentation patterns, provided an unambiguous conformation. The method was linear (r2 > 0.9905; 0.5–25 ng ml?1), with LOQQ of 0.5 ng ml?1. Recoveries were in range 75–114%, while matrix effects were minimal. The experimental study was carried out on three groups of male Friesian veal calves: group PL (n = 6, PL acetate 15 mg day–1 p.o. for 31 days); group DX (n = 5, 5 mg of estradiol (E2) i.m., weekly, and 0.4 mg day–1 of DX p.o. for 31 days) and a control group (n = 8). Urine was collected before, during (twice) and at the end of treatment. During PL administration, the tetrahydro-metabolite levels decreased gradually and remained low after the suspension of treatment. DX reduced urinary THF that persisted after the treatment, while THE levels decreased during the experiment, but rebounded substantially after the DX was withdrawn. Both DX and PL significantly interfered with the production of F and E, leading to their complete depletion. Taken together, the results demonstrate the influence of DX and PL administration on 11βHSD activity and their impact on dysfunction of the 5-reductase pathway. In conclusion, profiling tetrahydro-metabolites of F and E might serve as an alternative, indirect but reliable, non-invasive procedure for assessing the impact of synthetic glucocorticosteroids administration. 相似文献
83.
Tommaso Piccoli Valeria Blandino Laura Maniscalco Domenica Matranga Fabiola Graziano Fabrizio Guajana Luisa Agnello Bruna Lo Sasso Caterina Maria Gambino Rosaria Vincenza Giglio Vincenzo La Bella Marcello Ciaccio Tiziana Colletti 《International journal of molecular sciences》2022,23(18)
Recently, the synaptic proteins neurogranin (Ng) and α-synuclein (α-Syn) have attracted scientific interest as potential biomarkers for synaptic dysfunction in neurodegenerative diseases. In this study, we measured the CSF Ng and α-Syn concentrations in patients affected by AD (n = 69), non-AD neurodegenerative disorders (n-AD = 50) and non-degenerative disorders (n-ND, n = 98). The concentrations of CSF Ng and α-Syn were significantly higher in AD than in n-AD and n-ND. Moreover, the Aβ42/Ng and Aβ42/α-Syn ratios showed statistically significant differences between groups and discriminated AD patients from n-AD patients, better than Ng or α-Syn alone. Regression analyses showed an association of higher Ng concentrations with MMSE < 24, pathological Aβ 42/40 ratios, pTau, tTau and the ApoEε4 genotype. Aβ 42/Ng was associated with MMSE < 24, an AD-related FDG-PET pattern, the ApoEε4 genotype, pathological Aβ 42 levels and Aβ 42/40 ratios, pTau, and tTau. Moreover, APO-Eε4 carriers showed higher Ng concentrations than non-carriers. Our results support the idea that the Aβ 42/Ng ratio is a reliable index of synaptic dysfunction/degeneration able to discriminate AD from other neurological conditions. 相似文献
84.
Linear Logic is gaining momentum in computer science because it offers a unified framework and a common vocabulary for studying and analyzing different aspects of programming and computation. We focus here on models where computation is identified with proof search in the sequent system of Linear Logic. A proof normalization procedure, called “focusing”, has been proposed to make the problem of proof search tractable. Correspondingly, there is a normalization procedure mapping formulae of Linear Logic into a syntactic fragment of that logic, calledLinLog, where the focusing normalization for proofs can be most conveniently expressed. In this paper, we propose to push this compilation/normalization process further, by applying abstract interpretation and partial evaluation techniques to (focused) proofs inLinLog. These techniques provide information concerning the evolution of the computational resources (formulae) during the execution (proof construction). The practical outcome that we expect from this theoretical effort is the definition of a general tool for statically analyzing and reasoning about the runtime behavior of programs in frameworks where computations can be accounted for in terms of proof search in Linear Logic. 相似文献
85.
Tiziana Catarci Shi Kuo Chang Giuseppe Santucci 《Journal of Intelligent Information Systems》1994,3(3-4):299-330
We propose a framework for database querying providing the user with several interaction paradigms based on different (i.e., form-based, diagrammatic, iconic, and hybrid) visual representations of the database. A unified model, namely the Graph Model, is used as the common underlying model, in terms of which databases expressed in the most common data models can be easily converted. Graph Model databases can be queried by means of the multiparadigmatic interface. The semantics of the query operations is formally defined in terms of the Graphical Primitives. Such a formal approach enables the query manager to maintain the same query consistently in any representation. In the proposed multiparadigmatic environment, the user can switch from one interaction paradigm to another during query formulation, so that the most suitable query representation can be found. 相似文献
86.
Antonio Boccaccio Maria Cristina Frassanito Luciano Lamberti Roberto Brunelli Giuseppe Maulucci Maurizio Monaci Massimiliano Papi Carmine Pappalettere Tiziana Parasassi Lakamy Sylla Fulvio Ursini Marco De Spirito 《Journal of the Royal Society Interface》2012,9(76):2871-2882
The zona pellucida (ZP) is an extracellular membrane surrounding mammalian oocytes. The so-called zona hardening plays a key role in fertilization process, as it blocks polyspermy, which may also be caused by an increase in the mechanical stiffness of the ZP membrane. However, structural reorganization mechanisms leading to ZP''s biomechanical hardening are not fully understood yet. Furthermore, a correct estimate of the elastic properties of the ZP is still lacking. Therefore, the aim of the present study was to investigate the biomechanical behaviour of ZP membranes extracted from mature and fertilized bovine oocytes to better understand the mechanisms involved in the structural reorganization of the ZP that may lead to the biomechanical hardening of the ZP. For that purpose, a hybrid procedure is developed by combining atomic force microscopy nanoindentation measurements, nonlinear finite element analysis and nonlinear optimization. The proposed approach allows us to determine the biomechanical properties of the ZP more realistically than the classical analysis based on Hertz''s contact theory, as it accounts for the nonlinearity of finite indentation process, hyperelastic behaviour and material heterogeneity. Experimental results show the presence of significant biomechanical hardening induced by the fertilization process. By comparing various hyperelastic constitutive models, it is found that the Arruda–Boyce eight-chain model best describes the biomechanical response of the ZP. Fertilization leads to an increase in the degree of heterogeneity of membrane elastic properties. The Young modulus changes sharply within a superficial layer whose thickness is related to the characteristic distance between cross-links in the ZP filamentous network. These findings support the hypothesis that biomechanical hardening of bovine ZP is caused by an increase in the number of inter-filaments cross-links whose density should be higher in the ZP inner side. 相似文献
87.
Angelita Gambuti Rosa Capuano Maria Tiziana Lisanti Daniela Strollo Luigi Moio 《European Food Research and Technology》2010,231(3):455-465
This study provides specific information about the influence of storage in bottle and in 225-L barrels made from oak (new
and used for 1 year) and chestnut wood on color indexes, spectrophotometric evaluable polyphenols, anthocyanins, phenolic
acids and gustative attributes of three monovarietal red wines (Piedirosso, Cabernet Sauvignon and Merlot). The results of
the analysis of variance show that wood type has a significant influence on chromatic characteristics, on vanilline reactive
flavans, on low molecular weight phenolics and on astringency of wines. The effect depends on the type of wine. Therefore,
both traditional and alternative wood containers could be used as an instrument to regulate the polymerization, oxidation
and copigmentation reaction of wine phenolics and the sensory properties of red wine. The maturation in chestnut wood could
be an interesting challenge to widen the supply of red wines maturated in wood, but its use needs more care than oak. 相似文献
88.
89.
90.
Tiziana Vaval Annamaria Catino Pamela Pizzutilo Vito Longo Domenico Galetta 《International journal of molecular sciences》2021,22(21)
In developed countries, lung cancer is the leading cause of cancer-related death in both sexes. Although cigarette smoking represents the principal risk factor for lung cancer in females, the higher proportion of this neoplasm among non-smoking women as compared with non-smoking men implies distinctive biological aspects between the two sexes. Gender differences depend not only on genetic, environmental, and hormonal factors but also on the immune system, and all these aspects are closely interconnected. In the last few years, it has been confirmed that the immune system plays a fundamental role in cancer evolution and response to oncological treatments, specifically immunotherapy, with documented distinctions between men and women. Consequently, in order to correctly assess cancer responses and disease control, considering only age and reproductive status, the results of studies conducted in female patients would probably not categorically apply to male patients and vice versa. The aim of this article is to review recent data about gender disparities in both healthy subjects’ immune system and lung cancer patients; furthermore, studies concerning gender differences in response to lung cancer immunotherapy are examined. 相似文献