全文获取类型
收费全文 | 607篇 |
免费 | 48篇 |
专业分类
电工技术 | 7篇 |
综合类 | 1篇 |
化学工业 | 217篇 |
金属工艺 | 14篇 |
机械仪表 | 26篇 |
建筑科学 | 18篇 |
矿业工程 | 1篇 |
能源动力 | 15篇 |
轻工业 | 145篇 |
水利工程 | 2篇 |
石油天然气 | 9篇 |
无线电 | 30篇 |
一般工业技术 | 76篇 |
冶金工业 | 36篇 |
原子能技术 | 4篇 |
自动化技术 | 54篇 |
出版年
2024年 | 1篇 |
2023年 | 9篇 |
2022年 | 42篇 |
2021年 | 33篇 |
2020年 | 22篇 |
2019年 | 26篇 |
2018年 | 19篇 |
2017年 | 25篇 |
2016年 | 26篇 |
2015年 | 15篇 |
2014年 | 39篇 |
2013年 | 53篇 |
2012年 | 38篇 |
2011年 | 40篇 |
2010年 | 24篇 |
2009年 | 27篇 |
2008年 | 29篇 |
2007年 | 32篇 |
2006年 | 22篇 |
2005年 | 19篇 |
2004年 | 14篇 |
2003年 | 8篇 |
2002年 | 11篇 |
2001年 | 6篇 |
2000年 | 8篇 |
1999年 | 5篇 |
1998年 | 8篇 |
1997年 | 9篇 |
1996年 | 6篇 |
1995年 | 5篇 |
1994年 | 5篇 |
1993年 | 3篇 |
1990年 | 1篇 |
1989年 | 5篇 |
1988年 | 3篇 |
1987年 | 1篇 |
1986年 | 3篇 |
1985年 | 1篇 |
1984年 | 2篇 |
1983年 | 2篇 |
1982年 | 1篇 |
1980年 | 2篇 |
1979年 | 2篇 |
1977年 | 1篇 |
1976年 | 2篇 |
排序方式: 共有655条查询结果,搜索用时 15 毫秒
61.
62.
Nadielly R. Andrade Silva Marcos A. C. Luna André L. C. M. A. Santiago Luciana O. Franco Grayce K. B. Silva Patrícia M. de Souza Kaoru Okada Clarissa D. C. Albuquerque Carlos A. Alves da Silva Galba M. Campos-Takaki 《International journal of molecular sciences》2014,15(9):15377-15395
A Mucoralean fungus was isolated from Caatinga soil of Pernambuco, Northeast of Brazil, and was identified as Cunninghamella echinulata by morphological, physiological, and biochemical tests. This strain was evaluated for biosurfactant/bioemulsifier production using soybean oil waste (SOW) and corn steep liquor (CSL) as substrates, added to basic saline solution, by measuring surface tension and emulsifier index and activity. The best results showed the surface water tension was reduced from 72 to 36 mN/m, and an emulsification index (E24) of 80% was obtained using engine oil and burnt engine oil, respectively. A new molecule of biosurfactant showed an anionic charge and a polymeric chemical composition consisting of lipids (40.0% w/w), carbohydrates (35.2% w/w) and protein (20.3% w/w). In addition, the biosurfactant solution (1%) demonstrated its ability for an oil displacement area (ODA) of 37.36 cm2, which is quite similar to that for Triton X-100 (38.46 cm2). The stability of the reduction in the surface water tension as well as of the emulsifier index proved to be stable over a wide range of temperatures, in pH, and in salt concentration (4%–6% w/v). The biosurfactant showed an ability to reduce and increase the viscosity of hydrophobic substrates and their molecules, suggesting that it is a suitable candidate for mediated enhanced oil recovery. At the same time, these studies indicate that renewable, relatively inexpensive and easily available resources can be used for important biotechnological processes. 相似文献
63.
Thermophiles as Potential Source of Novel Endotoxin Antagonists: the Full Structure and Bioactivity of theLipo‐oligosaccharide from Thermomonas hydrothermalis 下载免费PDF全文
Dr. Flaviana Di Lorenzo Dr. Ida Paciello Dr. Luigi Lembo Fazio Dr. Luciana Albuquerque Dr. Luisa Sturiale Prof. Milton S. da Costa Prof. Rosa Lanzetta Prof. Michelangelo Parrilli Prof. Domenico Garozzo Prof. Maria Lina Bernardini Dott. Alba Silipo Prof. Antonio Molinaro 《Chembiochem : a European journal of chemical biology》2014,15(14):2146-2155
Thermomonas hydrothermalis is a Gram‐negative thermophilic bacterium that is able to live at 50 °C. This ability is attributed to chemical modifications, involving those to bacterial cell‐wall components, such as proteins and (glyco)lipids. As the main component of the outer membrane of Gram‐negative bacteria, lipopolysaccharides (LPSs) are exposed to the environment, thus they can undergo structural chemical changes to allow thermophilic bacteria to live at their optimal growth temperature. Furthermore, as one of the major target of the eukaryotic innate immune system, LPS elicits host immune response in a structure‐dependent mode; thus the uncommon chemical features of thermophilic bacterial LPSs might exert a different biological action on the innate immune system—an antagonistic effect, as shown in studies of LPS structure–activity relationship in the ongoing research into antagonist LPS candidates. Here, we report the complete structural and biological activity analysis of the lipo‐oligosaccharide isolated from Thermomonas hydrothermalis, achieved by a multidisciplinary approach (chemical analysis, NMR, MALDI MS and cellular immunology). We demonstrate a tricky and interesting structure combined with a very interesting effect on human innate immunity. 相似文献
64.
Inside Cover: Site‐Specific Modification of the Anticancer and Antituberculosis Polyether Salinomycin by Biosynthetic Engineering (ChemBioChem 14/2014) 下载免费PDF全文
65.
Luciana R. Pires KassabMauricio Eiji Camilo Ali H. Reshak K.J. Plucinski 《Materials Letters》2011,65(10):1445-1447
We have observed substantial influence of the illumination by 3.5 μs CO2 laser on the piezooptical coefficients of 59 PbO - 41 GeO2 (in wt.%) glasses prepared with Tm2O3, Er2O3, Yb2O3 using the following concentrations (in wt.%): B-Tm2O3 (0.5)/Yb2O3 (1.0)/Er2O3(0.5); C-Tm2O3(0.5)/Yb2O3(1.0)/Er2O3 O(1.0); D-Tm2O3 (0.5)/Yb2O3 (1.0)/Er 2O3 (2.0). We have found that the maximal changes were observed for B samples that contain the lowest concentration of Er2O3. The maximal changes are observed around 360 nm near the fundamental absorption edge. There exists some correlation between the maximal intensities of the photoluminescence and the maximal piezooptical changes. The CO2 lasers cause preliminary photothermal changes. The existence of the maxima may be caused by a competition between the phonon and anharmonic phonon subsystems, which are very sensitive to the temperature. 相似文献
66.
Laise Maia Lopes Gabriel Yoshiaki Ottaiano Luciana de Souza Guedes Mariana Agostini de Moraes Marisa Masumi Beppu 《应用聚合物科学杂志》2024,141(19):e55343
Mucin, a glycoprotein with viscoelastic properties, and silk fibroin, a protein excreted from silkworms with properties of thermal and mechanical resistance, have been probed as building blocks in the design of biomaterials. Aiming to evaluate the interaction and miscibility between mucin and fibroin, we synthesized silk fibroin and mucin (SF/MU) blends for biomedical applications. The morphological analysis of the SF/MU blends showed the presence of two phases, suggesting a partial miscibility between the polymers. The degradation temperature of the SF/MU blends increased with an increase in the silk fibroin content, indicating that silk fibroin contributed to the thermal stability of the blends. The glass transition temperature of the SF/MU blends lay between the values of the pure polymers. The Fourier-transform infrared spectroscopy results pointed out that the interaction between fibroin and mucin occurred between the amine group of silk fibroin and mucin carboxyl and hydroxyl groups. The outcomes of this work provided essential information on the miscibility of the SF/MU blends. These findings will be critical for further studies with fibroin and mucin-based biomaterials, especially in mucoadhesive systems and wound healing applications. 相似文献
67.
Priscila M. P. Souza Diego Carballares Luciana R. B. Gonalves Roberto Fernandez-Lafuente Sueli Rodrigues 《International journal of molecular sciences》2022,23(22)
Lipase B from Candida antarctica was immobilized on heterofunctional support octyl agarose activated with vinyl sulfone to prevent enzyme release under drastic conditions. Covalent attachment was established, but the blocking step using hexylamine, ethylenediamine or the amino acids glycine (Gly) and aspartic acid (Asp) altered the results. The activities were lower than those observed using the octyl biocatalyst, except when using ethylenediamine as blocking reagent and p-nitrophenol butyrate (pNPB) as substrate. The enzyme stability increased using these new biocatalysts at pH 7 and 9 using all blocking agents (much more significantly at pH 9), while it decreased at pH 5 except when using Gly as blocking agent. The stress inactivation of the biocatalysts decreased the enzyme activity versus three different substrates (pNPB, S-methyl mandelate and triacetin) in a relatively similar fashion. The tryptophane (Trp) fluorescence spectra were different for the biocatalysts, suggesting different enzyme conformations. However, the fluorescence spectra changes during the inactivation were not too different except for the biocatalyst blocked with Asp, suggesting that, except for this biocatalyst, the inactivation pathways may not be so different. 相似文献
68.
Simone Dinarelli Giovanni Longo Antonio Francioso Luciana Mosca Marco Girasole 《International journal of molecular sciences》2022,23(17)
Erythrocytes’ aging and mechano-transduction are fundamental cellular pathways that determine the red blood cells’ (RBCs) behavior and function. The aging pattern can be influenced, in morphological, biochemical, and metabolic terms by the environmental conditions. In this paper, we studied the effect of a moderate mechanical stimulation applied through external shaking during the RBCs aging and revealed a strong acceleration of the aging pattern induced by such stimulation. Moreover, we evaluated the behavior of the main cellular effectors and resources in the presence of drugs (diamide) or of specific inhibitors of the mechano-transduction (probenecid, carbenoxolone, and glibenclamide). This approach provided the first evidence of a direct cross-correlation between aging and mechano-transduction and permitted an evaluation of the overall metabolic regulation and of the insurgence of specific morphological features, such as micro-vesicles and roughness alterations. Overall, for the first time the present data provided a schematic to understand the integration of distinct complex patterns in a comprehensive view of the cell and of its interactions with the environment. Mechano-transduction produces structural effects that are correlated with the stimulation and the strength of the environmental stimulation is paramount to effectively activate and trigger the biological cascades initiated by the mechano-sensing. 相似文献
69.
Lucas Bayons María Jos Guerra-Fernndez Fernando Hinostroza Ximena Bez-Matus Jacqueline Vsquez-Navarrete Luciana I. Gallo Sergio Parra Agustín D. Martínez Arlek Gonzlez-Jamett Fernando D. Marengo Ana M. Crdenas 《International journal of molecular sciences》2022,23(18)
Gain-of-function mutations of dynamin-2, a mechano-GTPase that remodels membrane and actin filaments, cause centronuclear myopathy (CNM), a congenital disease that mainly affects skeletal muscle tissue. Among these mutations, the variants p.A618T and p.S619L lead to a gain of function and cause a severe neonatal phenotype. By using total internal reflection fluorescence microscopy (TIRFM) in immortalized human myoblasts expressing the pH-sensitive fluorescent protein (pHluorin) fused to the insulin-responsive aminopeptidase IRAP as a reporter of the GLUT4 vesicle trafficking, we measured single pHluorin signals to investigate how p.A618T and p.S619L mutations influence exocytosis. We show here that both dynamin-2 mutations significantly reduced the number and durations of pHluorin signals induced by 10 μM ionomycin, indicating that in addition to impairing exocytosis, they also affect the fusion pore dynamics. These mutations also disrupt the formation of actin filaments, a process that reportedly favors exocytosis. This altered exocytosis might importantly disturb the plasmalemma expression of functional proteins such as the glucose transporter GLUT4 in skeletal muscle cells, impacting the physiology of the skeletal muscle tissue and contributing to the CNM disease. 相似文献
70.
Angela Cozma Nicolae Dan Sporis Andrada Luciana Lazar Andrei Buruiana Andreea Maria Ganea Toma Vlad Malinescu Bianca Mihaela Berechet Adriana Fodor Adela Viviana Sitar-Taut Vasile Calin Vlad Vasile Negrean Olga Hilda Orasan 《International journal of molecular sciences》2022,23(18)
Immune checkpoint inhibitors (ICIs) are an important advancement in the field of cancer treatment, significantly improving the survival of patients with a series of advanced malignancies, like melanoma, non-small cell lung cancer (NSCLC), hepatocellular carcinoma (HCC), renal cell carcinoma (RCC), and Hodgkin lymphoma. ICIs act upon T lymphocytes and antigen-presenting cells, targeting programmed cell death protein 1 (PD1), programmed cell death protein ligand 1 (PD-L1), and cytotoxic T-lymphocyte antigen 4 (CTLA-4), breaking the immune tolerance of the T cells against malignant cells and enhancing the body’s own immune response. A variety of cardiac-adverse effects are associated with ICI-based treatment, including pericarditis, arrhythmias, cardiomyopathy, and acute coronary syndrome, with myocarditis being the most studied due to its often-unexpected onset and severity. Overall, Myocarditis is rare but presents an immune-related adverse event (irAE) that has a high fatality rate. Considering the rising number of oncological patients treated with ICIs and the severity of their potential adverse effects, a good understanding and continuous investigation of cardiac irAEs is of the utmost importance. This systematic review aimed to revise recent publications (between 2016–2022) on ICI-induced cardiac toxicities and highlight the therapeutical approach and evolution in the selected cases. 相似文献