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41.
Cold groundwater temperatures and conductive heat flow in the Mt. Amiata geothermal area, Tuscany, Italy 总被引:1,自引:0,他引:1
Giovanni Chiodini Paola Comodi Stefano Giaquinto Bruno Mattioli Anna Rosa Zanzari 《Geothermics》1988,17(4)
The hydrogeochemical study of the cold springs present in the Mt. Amiata geothermal area, where the Bagnore and Piancastagnaio geothermal fields are situated, has defined the different shallow groundwater systems.The cold groundwater temperature of the volcanic phreatic aquifer is largely correlated with the geothermal heat flow. Through the analysis of the temperature of cold groundwaters, a possible method for geothermal prospection has been developed, supported by the results obtained in the studied area. Through the enthalpic balance of the aquifer and in agreement with available data, a geothermal flow of about 200 mW m-2 has been calculated. 相似文献
42.
Simonetta Pazzaglia Barbara Tanno Ilaria De Stefano Paola Giardullo Simona Leonardi Caterina Merla Gabriele Babini Seda Tuncay Cagatay Ammar Mayah Munira Kadhim Fiona M. Lyng Christine von Toerne Zohaib N. Khan Prabal Subedi Soile Tapio Anna Saran Mariateresa Mancuso 《International journal of molecular sciences》2022,23(4)
Cell communication via exosomes is capable of influencing cell fate in stress situations such as exposure to ionizing radiation. In vitro and in vivo studies have shown that exosomes might play a role in out-of-target radiation effects by carrying molecular signaling mediators of radiation damage, as well as opposite protective functions resulting in resistance to radiotherapy. However, a global understanding of exosomes and their radiation-induced regulation, especially within the context of an intact mammalian organism, has been lacking. In this in vivo study, we demonstrate that, compared to sham-irradiated (SI) mice, a distinct pattern of proteins and miRNAs is found packaged into circulating plasma exosomes after whole-body and partial-body irradiation (WBI and PBI) with 2 Gy X-rays. A high number of deregulated proteins (59% of WBI and 67% of PBI) was found in the exosomes of irradiated mice. In total, 57 and 13 miRNAs were deregulated in WBI and PBI groups, respectively, suggesting that the miRNA cargo is influenced by the tissue volume exposed to radiation. In addition, five miRNAs (miR-99b-3p, miR-200a-3p, miR-200a, miR-182-5p, miR-182) were commonly overexpressed in the exosomes from the WBI and PBI groups. In this study, particular emphasis was also given to the determination of the in vivo effect of exosome transfer by intracranial injection in the highly radiosensitive neonatal cerebellum at postnatal day 3. In accordance with a major overall anti-apoptotic function of the commonly deregulated miRNAs, here, we report that exosomes from the plasma of irradiated mice, especially in the case of WBI, prevent radiation-induced apoptosis, thus holding promise for exosome-based future therapeutic applications against radiation injury. 相似文献
43.
Valeria Fedeli Alessandra Cucina Simona Dinicola Gianmarco Fabrizi Angela Catizone Luisa Gesualdi Simona Ceccarelli Abdel Halim Harrath Saleh H. Alwasel Giulia Ricci Paola Pedata Mariano Bizzarri Noemi Monti 《International journal of molecular sciences》2022,23(4)
Microgravity impairs tissue organization and critical pathways involved in the cell–microenvironment interplay, where fibroblasts have a critical role. We exposed dermal fibroblasts to simulated microgravity by means of a Random Positioning Machine (RPM), a device that reproduces conditions of weightlessness. Molecular and structural changes were analyzed and compared to control samples growing in a normal gravity field. Simulated microgravity impairs fibroblast conversion into myofibroblast and inhibits their migratory properties. Consequently, the normal interplay between fibroblasts and keratinocytes were remarkably altered in 3D co-culture experiments, giving rise to several ultra-structural abnormalities. Such phenotypic changes are associated with down-regulation of α-SMA that translocate in the nucleoplasm, altogether with the concomitant modification of the actin-vinculin apparatus. Noticeably, the stress associated with weightlessness induced oxidative damage, which seemed to concur with such modifications. These findings disclose new opportunities to establish antioxidant strategies that counteract the microgravity-induced disruptive effects on fibroblasts and tissue organization. 相似文献
44.
Polyacrylamides can be readily characterized using techniques such as IR spectroscopy, 13C-NMR, elementary analysis, TGA, and x-ray diffraction. The first three techniques can also be used quantitatively to measure the degree of hydrolysis of the polymers, without the need to know accurately the weight of the sample. The presence of inorganic salts, such as Na2SO4, Na4(CO3)SO4, and Na2CO3, is readily detected via IR or wide-angle x-ray diffraction. No evidence of crystallinity is found in the samples studied. 相似文献
45.
Pedrini Matteo Langella Valentina Battaglia Mario Alberto Zaratin Paola 《Scientometrics》2018,114(3):1227-1250
Scientometrics - In recent year, a growing attention is dedicated to the assessment of research’s social impact. While prior research has often dealt with results of research, the last decade... 相似文献
46.
The high affinity growth hormone-binding protein (GHBP) circulates in human blood and represents the extracellular domain of the growth hormone (GH) receptor. It is well known that repetitive bouts of endurance type exercise result in increased integrated GH secretion. As the effects of chronic exercise on plasma GHBP levels have never been studied systematically, we investigated the effect of 2 weeks of intense endurance training on plasma GHBP as well as on plasma insulin-like growth factor (IGF)-I levels in 10 healthy, young, non-obese men. IGF-I was measured as an indicator of the effects of GH release. We also studied 10 control subjects matched for sex, age and activity, who were instructed not to change their customary activities. GHBP was determined by FPLC size exclusion chromatography and subsequent Scatchard plot analysis of the binding data; IGF-I levels were measured by RIA. The results showed that plasma IGF-I and GHBP levels were increased in the subjects who followed the training program. IGF-I and GHBP changed from 252 +/- 56 ng/ml and 912 +/- 59 pmol/l before training, to 344 +/- 61 ng/ml (p < 0.01) and 1020 +/- 48 pmol/l (p < 0.01), respectively. Another effect of the training was that the aerobic capacity of these subjects was better utilized and endurance was improved. In contrast, plasma IGF-I, GHBP, utilization of aerobic capacity and endurance did not change significantly in the control subjects. We conclude that two weeks of strenuous endurance training lead to increased plasma IGF-I and high affinity GHBP levels. 相似文献
47.
Marta Brambilla Maria Talmon Paola Canzano Luigia G. Fresu Sandra Brunelleschi Elena Tremoli Marina Camera 《International journal of molecular sciences》2022,23(9)
Several contributions of circulating microvesicles (MVs) to the endothelial dysfunction have been reported in the past; a head-to-head comparison of platelet- and monocyte–derived MVs has however never been performed. To this aim, we assessed the involvement of these MVs in vessel damage related processes, i.e., oxidative stress, inflammation, and leukocyte-endothelial adhesion. Platelets and monocytes isolated from healthy subjects (HS, n = 15) were stimulated with TRAP-6 and LPS to release MVs that were added to human vascular endothelial cell (hECV) culture to evaluate superoxide anion production, inflammatory markers (IL-6, TNFα, NF-κB mRNA expression), and hECV adhesiveness. The effects of the MVs-induced from HS were compared to those induced by MVs spontaneously released from cells of patients with ST-segment elevation myocardial infarction (STEMI, n = 7). MVs released by HS-activated cells triggered a threefold increase in oxidative burst in a concentration-dependent manner. Only MVs released from monocytes doubled IL-6, TNFα, and NF-κB mRNA expression and monocyte-endothelial adhesion. Interestingly, the effects of the MVs isolated from STEMI-monocytes were not superimposable to previous ones except for adhesion to hECV. Conversely, MVs released from STEMI-platelets sustained both redox state and inflammatory phenotype. These data provide evidence that MVs released from activated and/or pathologic platelets and monocytes differently affect endothelial behavior, highlighting platelet-MVs as causative factors of impaired endothelial function in the acute phase of STEMI. 相似文献
48.
Carolina Gismene Jorge Enrique Hernndez Gonzlez Angela Rocio Nio Santisteban Andrey Fabricio Ziem Nascimento Lucas dos Santos Cunha Fbio Rogrio de Moraes Cristiano Luis Pinto de Oliveira Caio C. Oliveira Paola Jocelan Scarin Provazzi Pedro Geraldo Pascutti Raghuvir Krishnaswamy Arni Ricardo Barros Mariutti 《International journal of molecular sciences》2022,23(17)
Staphylococcal exfoliative toxins (ETs) are glutamyl endopeptidases that specifically cleave the Glu381-Gly382 bond in the ectodomains of desmoglein 1 (Dsg1) via complex action mechanisms. To date, four ETs have been identified in different Staphylococcus aureus strains and ETE is the most recently characterized. The unusual properties of ETs have been attributed to a unique structural feature, i.e., the 180° flip of the carbonyl oxygen (O) of the nonconserved residue 192/186 (ETA/ETE numbering), not conducive to the oxyanion hole formation. We report the crystal structure of ETE determined at 1.61 Å resolution, in which P186(O) adopts two conformations displaying a 180° rotation. This finding, together with free energy calculations, supports the existence of a dynamic transition between the conformations under the tested conditions. Moreover, enzymatic assays showed no significant differences in the esterolytic efficiency of ETE and ETE/P186G, a mutant predicted to possess a functional oxyanion hole, thus downplaying the influence of the flip on the activity. Finally, we observed the formation of ETE homodimers in solution and the predicted homodimeric structure revealed the participation of a characteristic nonconserved loop in the interface and the partial occlusion of the protein active site, suggesting that monomerization is required for enzymatic activity. 相似文献
49.
Paola Zanetta Diletta Francesca Squarzanti Alessia di Coste Roberta Rolla Paolo Aluffi Valletti Massimiliano Garzaro Valeria DellEra Angela Amoruso Marco Pane Barbara Azzimonti 《International journal of molecular sciences》2022,23(24)
The human oral pathobionts Aggregatibacter actinomycetemcomitans, Streptococcus mitis and Streptococcus mutans, in dysbiosis-promoting conditions, lead to oral infections, which also represent a threat to human systemic health. This scenario may be worsened by antibiotic misuse, which favours multi-drug resistance, making the research on pathogen containment strategies more than crucial. Therefore, we aimed to in vitro select the most promising probiotic strains against oral pathogen growth, viability, biofilm formation, and co-aggregation capacity, employing both the viable probiotics and their cell-free supernatants (CFSs). Interestingly, we also assessed probiotic efficacy against the three-pathogen co-culture, mimicking an environment similar to that in vivo. Overall, the results showed that Lactobacillus CFSs performed better than the Bifidobacterium, highlighting Limosilactobacillus reuteri LRE11, Lacticaseibacillus rhamnosus LR04, Lacticaseibacillus casei LC04, and Limosilactobacillus fermentum LF26 as the most effective strains, opening the chance to deeper investigation of their action and CFS composition. Altogether, the methodologies presented in this study can be used for probiotic efficacy screenings, in order to better focus the research on a viable probiotic, or on its postbiotics, suitable in case of infections. 相似文献
50.
Bazzicalupi C Chioccioli M Sissi C Porcù E Bonaccini C Pivetta C Bencini A Giorgi C Valtancoli B Melani F Gratteri P 《ChemMedChem》2010,5(12):1995-2005
Three novel 2,7-substituted acridine derivatives were designed and synthesized to investigate the effect of this functionalization on their interaction with double-stranded and G-quadruplex DNA. Detailed investigations of their ability to bind both forms of DNA were carried out by using spectrophotometric, electrophoretic, and computational approaches. The ligands in this study are characterized by an open-chain (L1) or a macrocyclic (L2, L3) framework. The aliphatic amine groups in the macrocycles are joined by ethylene (L2) or propylene chains (L3). L1 behaved similarly to the lead compound m-AMSA, efficiently intercalating into dsDNA, but stabilizing G-quadruplex structures poorly, probably due to the modest stabilization effect exerted by its protonated polyamine chains. L2 and L3, containing small polyamine macrocyclic frameworks, are known to adopt a rather bent and rigid conformation; thus they are generally expected to be sterically impeded from recognizing dsDNA according to an intercalative binding mode. This was confirmed to be true for L3. Nevertheless, we show that L2 can give rise to efficient π-π and H-bonding interactions with dsDNA. Additionally, stacking interactions allowed L2 to stabilize the G-quadruplex structure: using the human telomeric sequence, we observed the preferential induction of tetrameric G-quadruplex forms. Thus, the presence of short ethylene spacers seems to be essential for obtaining a correct match between the binding sites of L2 and the nucleobases on both DNA forms investigated. Furthermore, current modeling methodologies, including docking and MD simulations and free energy calculations, provide structural evidence of an interaction mode for L2 that is different from that of L3; this could explain the unusual stabilizing ability of the ligands (L2>L3>L1) toward G-quadruplex that was observed in this study. 相似文献