全文获取类型
收费全文 | 2695篇 |
免费 | 166篇 |
专业分类
电工技术 | 22篇 |
综合类 | 1篇 |
化学工业 | 768篇 |
金属工艺 | 59篇 |
机械仪表 | 92篇 |
建筑科学 | 86篇 |
矿业工程 | 7篇 |
能源动力 | 102篇 |
轻工业 | 708篇 |
水利工程 | 20篇 |
石油天然气 | 17篇 |
无线电 | 115篇 |
一般工业技术 | 360篇 |
冶金工业 | 238篇 |
原子能技术 | 16篇 |
自动化技术 | 250篇 |
出版年
2024年 | 10篇 |
2023年 | 20篇 |
2022年 | 137篇 |
2021年 | 133篇 |
2020年 | 74篇 |
2019年 | 77篇 |
2018年 | 83篇 |
2017年 | 120篇 |
2016年 | 88篇 |
2015年 | 78篇 |
2014年 | 103篇 |
2013年 | 215篇 |
2012年 | 199篇 |
2011年 | 189篇 |
2010年 | 153篇 |
2009年 | 131篇 |
2008年 | 130篇 |
2007年 | 122篇 |
2006年 | 93篇 |
2005年 | 71篇 |
2004年 | 62篇 |
2003年 | 57篇 |
2002年 | 43篇 |
2001年 | 39篇 |
2000年 | 25篇 |
1999年 | 21篇 |
1998年 | 88篇 |
1997年 | 44篇 |
1996年 | 39篇 |
1995年 | 34篇 |
1994年 | 23篇 |
1993年 | 24篇 |
1992年 | 16篇 |
1991年 | 14篇 |
1990年 | 3篇 |
1989年 | 6篇 |
1988年 | 14篇 |
1987年 | 4篇 |
1986年 | 8篇 |
1985年 | 8篇 |
1984年 | 7篇 |
1983年 | 5篇 |
1982年 | 7篇 |
1981年 | 4篇 |
1980年 | 9篇 |
1979年 | 4篇 |
1977年 | 3篇 |
1976年 | 11篇 |
1975年 | 2篇 |
1969年 | 2篇 |
排序方式: 共有2861条查询结果,搜索用时 0 毫秒
951.
Paula Fabiana dos Santos Pereira Camila Cristina De Foggi Amanda Fernandes Gouveia Ivo Mateus Pinatti Luís Antnio Cabral Eva Guillamon Ivn Sorribes Miguel A. San-Miguel Carlos Eduardo Vergani Alexandre Zirpoli Simes Edison Z. da Silva Lacio Santos Cavalcante Rosa Llusar Elson Longo Juan Andrs 《International journal of molecular sciences》2022,23(18)
In this work, α-Ag2−2xCuxWO4 (0 ≤ x ≤ 0.16) solid solutions with enhanced antibacterial (against methicillin-resistant Staphylococcus aureus) and antifungal (against Candida albicans) activities are reported. A plethora of techniques (X-ray diffraction with Rietveld refinements, inductively coupled plasma atomic emission spectrometry, micro-Raman spectroscopy, attenuated total reflectance–Fourier transform infrared spectroscopy, field emission scanning electron microscopy, ultraviolet–visible spectroscopy, photoluminescence emissions, and X-ray photoelectron spectroscopy) were employed to characterize the as-synthetized samples and determine the local coordination geometry of Cu2+ cations at the orthorhombic lattice. To find a correlation between morphology and biocide activity, the experimental results were sustained by first-principles calculations at the density functional theory level to decipher the cluster coordinations and electronic properties of the exposed surfaces. Based on the analysis of the under-coordinated Ag and Cu clusters at the (010) and (101) exposed surfaces, we propose a mechanism to explain the biocide activity of these solid solutions. 相似文献
952.
Roberta Iacono Andrea Strazzulli Rosa Giglio Federica Bitetti Beatrice Cobucci-Ponzano Marco Moracci 《International journal of molecular sciences》2022,23(18)
The increasing interest for environmentally friendly technologies is driving the transition from fossil-based economy to bioeconomy. A key enabler for circular bioeconomy is to valorize renewable biomasses as feedstock to extract high value-added chemicals. Within this transition the discovery and the use of robust biocatalysts to replace toxic chemical catalysts play a significant role as technology drivers. To meet both the demands, we performed microbial enrichments on two energy crops, used as low-cost feed for extremophilic consortia. A culture-dependent approach coupled to metagenomic analysis led to the discovery of more than 300 glycoside hydrolases and to characterize a new -glucosidase from an unknown hyperthermophilic archaeon. Aglu1 demonstrated to be the most active archaeal GH31 on 4Np-α-Glc and it showed unexpected specificity vs. kojibiose, revealing to be a promising candidate for biotechnological applications such as the liquefaction/saccharification of starch. 相似文献
953.
Fabiola García-Andrade Rosa María Vigueras-Villaseor Margarita Dolores Chvez-Saldaa Julio Csar Rojas-Castaeda Ivn Uriel Bahena-Ocampo Elena Archaga-Ocampo Jos Díaz-Chvez Daniel Adrian Landero-Huerta 《International journal of molecular sciences》2022,23(18)
Some pediatric patients with cryptorchidism preserve cells with gonocyte characteristics beyond their differentiation period, which could support the theory of the gonocyte as a target for malignancy in the development of testicular neoplasia. One of the key molecules in gonocyte malignancy is represented by microRNAs (miRNAs). The goal of this review is to give an overview of miRNAs, a class of small non-coding RNAs that participate in the regulation of gene expression. We also aim to review the crucial role of several miRNAs that have been further described in the regulation of gonocyte differentiation to spermatogonia, which, when transformed, could give rise to germ cell neoplasia in situ, a precursor lesion to testicular germ cell tumors. Finally, the potential use of miRNAs as diagnostic and prognostic biomarkers in testicular neoplasia is addressed, due to their specificity and sensitivity compared to conventional markers, as well as their applications in therapeutics. 相似文献
954.
Silvia Romano Carmela Romano Martina Peconi Alessia Fiore Gianmarco Bellucci Emanuele Morena Fernanda Troili Virginia Cipollini Viviana Annibali Simona Giglio Rosella Mechelli Michela Ferraldeschi Liana Veneziano Elide Mantuano Gabriele Sani Andrea Vecchione Renato Umeton Franco Giubilei Marco Salvetti Rosa Maria Corbo Daniela Scarabino Giovanni Ristori 《International journal of molecular sciences》2022,23(20)
Plasma small RNAs have been recently explored as biomarkers in Huntington’s disease (HD). We performed an exploratory study on nine HD patients, eight healthy subjects (HS), and five psychiatric patients (PP; to control for iatrogenic confounder effects) through an Affymetrix-Gene-Chip-miRNA-Array. We validated the results in an independent population of 23 HD, 15 pre-HD, 24 PP, 28 Alzheimer’s disease (AD) patients (to control the disease-specificity) and 22 HS through real-time PCR. The microarray results showed higher levels of U13 small nucleolar RNA (SNORD13) in HD patients than controls (fold change 1.54, p = 0.003 HD vs. HS, and 1.44, p = 0.0026 HD vs. PP). In the validation population, a significant increase emerged with respect to both pre-HD and the control groups (p < 0.0001). SNORD13 correlated with the status of the mutant huntingtin carrier (r = 0.73; p < 0.001) and the disease duration (r = 0.59; p = 0.003). The receiver operating characteristic (ROC) curve analysis showed the high accuracy of SNORD13 in discriminating HD patients from other groups (AUC = 0.963). An interactome and pathway analysis on SNORD13 revealed enrichments for factors relevant to HD pathogenesis. We report the unprecedented finding of a potential disease-specific role of SNORD13 in HD. It seems to peripherally report a ‘tipping point’ in the pathogenic cascade at the neuronal level. 相似文献
955.
Margarita L Martinez-Fierro Idalia Garza-Veloz Maria Eugenia Castaeda-Lopez Dorothy Wasike Claudia Castruita-De la Rosa Iram Pablo Rodriguez-Sanchez Ivan Delgado-Enciso Jose Flores-Mendoza 《International journal of molecular sciences》2022,23(17)
The abnormal implantation of the trophoblast during the first trimester of pregnancy precedes the appearance of the clinical manifestations of preeclampsia (PE), which is a hypertensive disorder of pregnancy. In a previous study, which was carried out in a murine model of PE that was induced by NG-nitro-L-arginine methyl ester (L-NAME), we observed that the intravenous administration of fibroblast growth factor 2 (FGF2) had a hypotensive effect, improved the placental weight gain and attenuated the fetal growth restriction, and the morphological findings that were induced by L-NAME in the evaluated tissues were less severe. In this study, we aimed to determine the effect of FGF2 administration on the placental gene expression of the vascular endothelial growth factor (VEGFA), VEGF receptor 2 (VEGFR2), placental growth factor, endoglin (ENG), superoxide dismutase 1 (SOD1), catalase (CAT), thioredoxin (TXN), tumor protein P53 (P53), BCL2 apoptosis regulator, Fas cell surface death receptor (FAS), and caspase 3, in a Sprague Dawley rat PE model, which was induced by L-NAME. The gene expression was determined by a real-time polymerase chain reaction using SYBR green. Taking the vehicle or the L-NAME group as a reference, there was an under expression of placental VEGFA, VEGFR2, ENG, P53, FAS, SOD1, CAT, and TXN genes in the group of L-NAME + FGF2 (p < 0.05). The administration of FGF2 in the murine PE-like model that was induced by L-NAME reduced the effects that were generated by proteinuria and the increased BP, as well as the response of the expression of genes that participate in angiogenesis, apoptosis, and OS. These results have generated valuable information regarding the identification of molecular targets for PE and provide new insights for understanding PE pathogenesis. 相似文献
956.
Abrahan Hernndez-Hernndez Tayde Lpez-Santaella Aranxa Torres-Caballero Amarantha Serrato Ulises Torres-Flores Diego Montesinos-Valencia Fernando Chico-Ponce de Len Vicente Gonzlez-Carranza Samuel Torres-García Rosa Rebollar-Vega Inti Alberto De la Rosa-Velzquez Rosario Ortiz Monserrat Prez-Ramírez Normand García-Hernndez Antonio García-Mndez Francisco Arenas-Huertero 《International journal of molecular sciences》2022,23(20)
957.
Michela Bollati Kaliroi Peqini Luigi Barone Carmina Natale Marten Beeg Marco Gobbi Luisa Diomede Michelangelo Trucchi Matteo de Rosa Sara Pellegrino 《International journal of molecular sciences》2022,23(22)
Gelsolin amyloidosis (AGel) is characterized by multiple systemic and ophthalmic features resulting from pathological tissue deposition of the gelsolin (GSN) protein. To date, no cure is available for the treatment of any form of AGel. More than ten single-point substitutions in the GSN gene are responsible for the occurrence of the disease and, among them, D187N/Y is the most widespread variant. These substitutions undergo an aberrant proteolytic cascade, producing aggregation-prone peptides of 5 and 8 kDa, containing the Gelsolin Amyloidogenic Core, spanning residues 182–192 (GAC182–192). Following a structure-based approach, we designed and synthesized three novel sequence-specific peptidomimetics (LB-5, LB-6, and LB-7) built on a piperidine-pyrrolidine unnatural amino acid. LB-5 and LB-6, but not LB-7, efficiently inhibit the aggregation of the GAC182–192 amyloidogenic peptides at sub-stoichiometric concentrations. These peptidomimetics resulted also effective in vivo, in a C. elegans-based assay, in counteracting the proteotoxicity of aggregated GAC182–192. These data pave the way to a novel pharmacological strategy against AGel and also validate a toolbox exploitable in other amyloidogenic diseases. 相似文献
958.
Francesc Lordan Enric Tejedor Jorge Ejarque Roger Rafanell Javier Álvarez Fabrizio Marozzo Daniele Lezzi Raül Sirvent Domenico Talia Rosa M. Badia 《Journal of Grid Computing》2014,12(1):67-91
The rise of virtualized and distributed infrastructures has led to new challenges to accomplish the effective use of compute resources through the design and orchestration of distributed applications. As legacy, monolithic applications are replaced with service-oriented applications, questions arise about the steps to be taken in order to maximize the usefulness of the infrastructures and to provide users with tools for the development and execution of distributed applications. One of the issues to be solved is the existence of multiple cloud solutions that are not interoperable, which forces the user to be locked to a specific provider or to continuously adapt applications. With the objective of simplifying the programmers challenges, ServiceSs provides a straightforward programming model and an execution framework that helps on abstracting applications from the actual execution environment. This paper presents how ServiceSs transparently interoperates with multiple providers implementing the appropriate interfaces to execute scientific applications on federated clouds. 相似文献
959.
Emmanuel Pina-Jimnez Fernando Calzada Elihú Bautista Rosa María Ordoez-Razo Claudia Velzquez Elizabeth Barbosa Normand García-Hernndez 《International journal of molecular sciences》2021,22(19)
Sesquiterpene lactones are of pharmaceutical interest due their cytotoxic and antitumor properties, which are commonly found within plants of several genera from the Asteraceae family such as the Decachaeta genus. From Decachaeta incompta four heliangolide, namely incomptines A-D have been isolated. In this study, cytotoxic properties of incomptine A (IA) were evaluated on four lymphoma cancer cell lines: U-937, Farage, SU-DHL-2, and REC-1. The type of cell death induced by IA and its effects on U-937 cells were analyzed based on its capability to induce apoptosis and produce reactive oxygen species (ROS) through flow cytometry with 4′,6-diamidino-2-phenylindole staining, dual annexin V/DAPI staining, and dichlorofluorescein 2′,7′-diacetate, respectively. A differential protein expression analysis study was carried out by isobaric tags for relative and absolute quantitation (iTRAQ) through UPLC-MS/MS. Results reveal that IA exhibited cytotoxic activity against the cell line U-937 (CC50 of 0.12 ± 0.02 μM) and the incubation of these cells in presence of IA significantly increased apoptotic population and intracellular ROS levels. In the proteomic approach 1548 proteins were differentially expressed, out of which 587 exhibited a fold-change ≥ 1.5 and 961 a fold-change ≤ 0.67. Most of these differentially regulated proteins are involved in apoptosis, oxidative stress, glycolytic metabolism, or cytoskeleton structuration. 相似文献
960.
Chiara Platella Rosa Gaglione Ettore Napolitano Angela Arciello Valentina Pirota Filippo Doria Domenica Musumeci Daniela Montesarchio 《International journal of molecular sciences》2021,22(19)
G-quadruplex existence was proved in cells by using both antibodies and small molecule fluorescent probes. However, the G-quadruplex probes designed thus far are structure- but not conformation-specific. Recently, a core-extended naphthalene diimide (cex-NDI) was designed and found to provide fluorescent signals of markedly different intensities when bound to G-quadruplexes of different conformations or duplexes. Aiming at evaluating how the fluorescence behaviour of this compound is associated with specific binding modes to the different DNA targets, cex-NDI was here studied in its interaction with hybrid G-quadruplex, parallel G-quadruplex, and B-DNA duplex models by biophysical techniques, molecular docking, and biological assays. cex-NDI showed different binding modes associated with different amounts of stacking interactions with the three DNA targets. The preferential binding sites were the groove, outer quartet, or intercalative site of the hybrid G-quadruplex, parallel G-quadruplex, and B-DNA duplex, respectively. Interestingly, our data show that the fluorescence intensity of DNA-bound cex-NDI correlates with the amount of stacking interactions formed by the ligand with each DNA target, thus providing the rationale behind the conformation-sensitive properties of cex-NDI and supporting its use as a fluorescent probe of G-quadruplex structures. Notably, biological assays proved that cex-NDI mainly localizes in the G-quadruplex-rich nuclei of cancer cells. 相似文献