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171.
Karina Gonzlez-García Armando Lpez-Martínez Juan Manuel Velzquez-Enríquez Cecilia Zertuche-Martínez Gabriela Carrasco-Torres Luis Manuel Snchez-Navarro Saúl Villa-Trevio Rafael Baltirrez-Hoyos Vernica Rocío Vsquez-Garzn 《International journal of molecular sciences》2022,23(14)
Idiopathic pulmonary fibrosis (IPF) is a chronic lung disease characterized by parenchymal scarring, leading progressively to alveolar architecture distortion, respiratory failure, and eventually death. Currently, there is no effective treatment for IPF. Previously, 3′5-dimaleamylbenzoic acid (3′5-DMBA), a maleimide, demonstrated pro-apoptotic, anti-inflammatory, and anti-cancer properties; however, its potential therapeutic effects on IPF have not been addressed. Bleomycin (BLM) 100 U/kg was administered to CD1 mice through an osmotic minipump. After fourteen days of BLM administration, 3′5-DMBA (6 mg/kg or 10 mg/kg) and its vehicle carboxymethylcellulose (CMC) were administered intragastrically every two days until day 26. On day 28, all mice were euthanized. The 3′5-DMBA effect was assessed by histological and immunohistochemical staining, as well as by RT-qPCR. The redox status on lung tissue was evaluated by determining the glutathione content and the GSH/GSSG ratio. 3′5-DMBA treatment re-established typical lung histological features and decreased the expression of BLM-induced fibrotic markers: collagen, α-SMA, and TGF-β1. Furthermore, 3′5-DMBA significantly reduced the expression of genes involved in fibrogenesis. In addition, it decreased reduced glutathione and increased oxidized glutathione content without promoting oxidative damage to lipids, as evidenced by the decrease in the lipid peroxidation marker 4-HNE. Therefore, 3′5-DMBA may be a promising candidate for IPF treatment. 相似文献
172.
Tommaso Palomba Giusy Tassone Carmine Vacca Matteo Bartalucci Aurora Valeri Cecilia Pozzi Simon Cross Lydia Siragusa Jenny Desantis 《International journal of molecular sciences》2022,23(22)
The field of targeted protein degradation, through the control of the ubiquitin–proteasome system (UPS), is progressing considerably; to exploit this new therapeutic modality, the proteolysis targeting chimera (PROTAC) technology was born. The opportunity to use PROTACs engaging of new E3 ligases that can hijack and control the UPS system could greatly extend the applicability of degrading molecules. To this end, here we show a potential application of the ELIOT (E3 LIgase pocketOme navigaTor) platform, previously published by this group, for a scaffold-repurposing strategy to identify new ligands for a novel E3 ligase, such as TRIM33. Starting from ELIOT, a case study of the cross-relationship using GRID Molecular Interaction Field (MIF) similarities between TRIM24 and TRIM33 binding sites was selected. Based on the assumption that similar pockets could bind similar ligands and considering that TRIM24 has 12 known co-crystalised ligands, we applied a scaffold-repurposing strategy for the identification of TRIM33 ligands exploiting the scaffold of TRIM24 ligands. We performed a deeper computational analysis to identify pocket similarities and differences, followed by docking and water analysis; selected ligands were synthesised and subsequently tested against TRIM33 via HTRF binding assay, and we obtained the first-ever X-ray crystallographic complexes of TRIM33α with three of the selected compounds. 相似文献
173.
174.
In this study, field observations were conducted after a heavy rainfall event in the Sumida and Shakujii rivers in Tokyo, Japan. The flow dynamics and fluxes of salt, suspended sediment (SS), and dissolved oxygen (DO) were investigated with the mass balance method. The fractions of fresh water and saltwater in seaward and landward flows were separated. The maximum salt flux in the Shakujii River was 53.8 kg/s during the flood tide, and those in the Sumida River were 680.3 kg/s at the upstream station and 703.7 kg/s at the downstream station. The trends of SS and DO fluxes were similar in both rivers. In the Shakujii River, the highest SS (3.1 kg/s) and DO (0.4 kg/s) fluxes appeared during the flood tide after rainfall. In the Sumida River, the maximum SS fluxes (6.1 and 6.3 kg/s at the upstream and downstream stations, respectively) and DO fluxes (1.15 and 1.21 kg/s at the upstream and downstream stations, respectively) appeared during the ebb tide. The mass balance method was used to estimate discharge, salinity, SS concentration, and DO concentration at a station with missing data. The results show that the estimated salinity and SS concentration had a significant correlation with the on-site observations, with correlation coefficients (R) of 0.950 and 0.835, respectively, but not for DO concentration (R = 0.638). The disparity between the computed and measured data may be explained by the differences in velocity, salinity, topography, sedimentation, and the presence of organic matter. The analysis based on the advective salt transport components found a lower salt flux per unit width in the Shakujii River (0.36 kg/(m·s)) in comparison with that in the Sumida River (2.88 kg/(m·s)). This indicates a higher probability for salt retention in the Shakujii River. 相似文献
175.
Violeta Paşcalău Emoke Pall Mihaela Tertis Maria Suciu Cecilia Cristea Gheorghe Borodi 《国际聚合物材料杂志》2019,68(1-3):60-72
AbstractThe aim of this study is to develop core shell microcapsules of bovine serum albumin (BSA) gel with a complex polyelectrolite multilayer shell of natural polysaccharides with opposite charges, pectin (P), chitosan (Chi), and hyaluronic acid (HA) respectively, encapsulating Doxorubicin (Dox) as a carrier for targeted anti-tumoral treatment of hepatic cell carcinoma (HCC). A sacrificial CaCO3 template method was used in order to obtain microcapsules with a BSA gel core and a layer-by-layer (Lbl) deposition technique of polyelectrolite complexes formed between P/Chi in the inner layers and HA/Chi in the outer shell layers. The preformed microcapsules, BSA gel/P/Chi/HA, noted as ms, have been applied for Dox encapsulation (ms-Dox). Dox encapsulation and release in different pH media were studied in order to elucidate the interactions between pH dependently charged species involved in the Dox loading/releasing processes. The structure characterization of ms/ms-Dox was evaluated by FTIR and UV-Vis spectroscopy, X-ray diffraction, thermal analy sis, optical microscopy, confocal laser scanning microscopy, and scanning electron microscopy. The in vitro study for citotoxicity assessment on normal and tumoral cells of both ms and ms-Dox was performed using mesenchymal stem cells (MSCs) and Hep2G HCC cell lines. Results of physical-chemical analyses confirm the successful encapsulation of Dox in ms, and the in vitro biological study recommends ms-Dox as a candidate for future in vivo research as a targeted anti-tumoral treatment modality applications. 相似文献
176.
Giuseppe Schepisi Caterina Gianni Sara Bleve Silvia De Padova Cecilia Menna Cristian Lolli Alessia Filograna Vincenza Conteduca Milena Urbini Valentina Gall Chiara Casadei Giovanni Rosti Ugo De Giorgi 《International journal of molecular sciences》2021,22(10)
Testicular cancer (TC) is the most frequent tumor in young males. In the vast majority of cases, it is a curable disease; therefore, very often patients experience a long survival, also due to their young age at diagnosis. In the last decades, the role of the vitamin D deficiency related to orchiectomy has become an increasingly debated topic. Indeed, vitamin D is essential in bone metabolism and many other metabolic pathways, so its deficiency could lead to various metabolic disorders especially in long-term TC survivors. In our article, we report data from studies that evaluated the incidence of hypovitaminosis D in TC survivors compared with cohorts of healthy peers and we discuss molecular mechanisms and clinical implications. 相似文献
177.
Manuela Moriggi Daniele Capitanio Enrica Torretta Pietro Barbacini Cinzia Bragato Patrizia Sartori Maurizio Moggio Lorenzo Maggi Marina Mora Cecilia Gelfi 《International journal of molecular sciences》2021,22(6)
Mutations in the acidic alpha-glucosidase (GAA) coding gene cause Pompe disease. Late-onset Pompe disease (LOPD) is characterized by progressive proximal and axial muscle weakness and atrophy, causing respiratory failure. Enzyme replacement therapy (ERT), based on recombinant human GAA infusions, is the only available treatment; however, the efficacy of ERT is variable. Here we address the question whether proteins at variance in LOPD muscle of patients before and after 1 year of ERT, compared withhealthy age-matched subjects (CTR), reveal a specific signature. Proteins extracted from skeletal muscle of LOPD patients and CTR were analyzed by combining gel based (two-dimensional difference gel electrophoresis) and label-free (liquid chromatography-mass spectrometry) proteomic approaches, and ingenuity pathway analysis. Upstream regulators targeting autophagy and lysosomal tethering were assessed by immunoblotting. 178 proteins were changed in abundance in LOPD patients, 47 of them recovered normal level after ERT. Defects in oxidative metabolism, muscle contractile protein regulation, cytoskeletal rearrangement, and membrane reorganization persisted. Metabolic changes, ER stress and UPR (unfolded protein response) contribute to muscle proteostasis dysregulation with active membrane remodeling (high levels of LC3BII/LC3BI) and accumulation of p62, suggesting imbalance in the autophagic process. Active lysosome biogenesis characterizes both LOPD PRE and POST, unparalleled by molecules involved in lysosome tethering (VAMP8, SNAP29, STX17, and GORASP2) and BNIP3. In conclusion this study reveals a specific signature that suggests ERT prolongation and molecular targets to ameliorate patient’s outcome. 相似文献
178.
179.
Dr. Cecilia Pozzi Dr. Flavio Di Pisa Dr. Filomena De Luca Dr. Manuela Benvenuti Prof. Jean Denis Docquier Prof. Stefano Mangani 《ChemMedChem》2018,13(14):1437-1446
β‐Lactamases (BLs) are important antibiotic‐resistance determinants that significantly compromise the efficacy of valuable β‐lactam antibacterial drugs. Thus, combinations with BL inhibitor were developed. Avibactam is the first non‐β‐lactam BL inhibitor introduced into clinical practice. Ceftazidime–avibactam represents one of the few last‐resort antibiotics available for the treatment of infections caused by near‐pandrug‐resistant bacteria. TRU‐1 is a chromosomally encoded AmpC‐type BL of Aeromonas enteropelogenes, related to the FOX‐type BLs and constitutes a good model for class C BLs. TRU‐1 crystals provided ultrahigh‐resolution diffraction data for the native enzyme and for its complex with avibactam. A comparison of the native and avibactam‐bound structures revealed new details in the conformations of residues relevant for substrate and/or inhibitor binding. Furthermore, a comparison of the TRU‐1 and Pseudomonas aeruginosa AmpC avibactam‐bound structures revealed two inhibitor conformations that were likely to correspond to two different states occurring during inhibitor carbamylation/recyclization. 相似文献
180.
G Perdigon M Medici M Cecilia M E de Macias R Haedo G Oliver A A de Ruiz Holgado 《Journal of dairy science》1986,69(1):27-31
The presence of beta-glucuronidase enzyme in bovine milk was related both to the existence of major and minor pathogens and to somatic cell counts. The detection of this enzyme in whole milk was made possible by the use of p-nitrophenyl-beta-glucuronide as a substrate. This detection allowed us to determine abnormal udder secretions with a high degree of specificity and sensitivity. The particular method of enzyme determination was considered important for mastitis detection because beta-D-glucuronidase, the most significant enzyme in inflammatory processes, is released selectively. The relationship between enzyme, presence of pathogens, and somatic cell counts was established in 220 milk samples obtained at random from individual quarters of apparently healthy udders of cows from four local dairy farms (Santiago del Estero and Tucuman, Argentina). Four of these samples were from cows of recent parturition and two from cows with severe clinical mastitis. Only 17% of the milk samples were normal with somatic cell counts 500,000 cells/ml or less. This ratio is the usual one throughout the area, and the remaining 83% showed higher somatic cell counts. Taking the latter as 100%, the presence of beta-glucuronidase and the positive bacteriological analyses represented 76 and 74%, respectively. 相似文献