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991.
Phytosterol Esterification is Markedly Decreased in Preterm Infants Receiving Routine Parenteral Nutrition 下载免费PDF全文
Sara Savini Alessio Correani Daniele Pupillo Rita D’Ascenzo Chiara Biagetti Adriana Pompilio Manuela Simonato Giovanna Verlato Paola Cogo Marina Taus Albano Nicolai Virgilio Paolo Carnielli 《Lipids》2016,51(12):1353-1361
Several studies reported the association between total plasma phytosterol concentrations and the parenteral nutrition‐associated cholestasis (PNAC). To date, no data are available on phytosterol esterification in animals and in humans during parenteral nutrition (PN). We measured free and esterified sterols (cholesterol, campesterol, stigmasterol, and sitosterol) plasma concentrations during PN in 16 preterm infants (500–1249 g of birth weight; Preterm‐PN), in 11 term infants (Term‐PN) and in 12 adults (Adult‐PN). Gas chromatography–mass spectrometry was used for measurements. Plasma concentrations of free cholesterol (Free‐CHO), free phytosterols (Free‐PHY) and esterified phytosterols (Ester‐PHY) were not different among the three PN groups. Esterified cholesterol (Ester‐CHO) was statistically lower in Preterm‐PN than Adult‐PN. Preterm‐PN had significantly higher Free‐CHO/Ester‐CHO and Free‐PHY/Ester‐PHY ratios than Adult‐PN (Free‐CHO/Ester‐CHO: 1.1 ± 0.7 vs. 0.6 ± 0.2; Free‐PHY/Ester‐PHY: 4.1 ± 2.6 vs. 1.3 ± 0.8; *P < 0.05). Free‐CHO/Ester‐CHO and Free‐PHY/Ester‐PHY ratios of Term‐PN (Free‐CHO/Ester‐CHO: 1.1 ± 0.4; Free‐PHY/Ester‐PHY: 2.9 ± 1.7) were not different from either Preterm‐PN or from Adult‐PN. Plasma Free‐CHO/Ester‐CHO and Free‐PHY/Ester‐PHY were unchanged after 24 h on fat‐free PN both in Preterm‐PN and in Adult‐PN. Free‐PHY/Ester‐PHY did not correlate with phytosterol intake in Preterm‐PN. Free‐PHY/Ester‐PHY of Preterm‐PN was positively correlated with the Free‐CHO/Ester‐CHO and negatively correlated with gestational age and birth weight. In conclusion, PHY were esterified to a lesser extent than CHO in all study groups; the esterification was markedly decreased in Preterm‐PN compared to Adult‐PN. The clinical consequences of these findings warrant further investigations. 相似文献
992.
993.
Giosuè Scognamiglio Anna De Chiara Maurizio Di Bonito Fabiana Tatangelo Nunzia Simona Losito Annamaria Anniciello Rossella De Cecio Crescenzo D’Alterio Stefania Scala Monica Cantile Gerardo Botti 《International journal of molecular sciences》2016,17(5)
In normal cell physiology, programmed death 1 (PD-1) and its ligand, PD-L1, play an immunoregulatory role in T-cell activation, tolerance, and immune-mediated tissue damage. The PD-1/PD-L1 pathway also plays a critical role in immune escape of tumor cells and has been demonstrated to correlate with a poor prognosis of patients with several types of cancer. However, recent reports have revealed that the immunohistochemical (IHC) expression of the PD-L1 in tumor cells is not uniform for the use of different antibodies clones, with variable specificity, often doubtful topographical localization, and with a score not uniquely defined. The purpose of this study was to analyze the IHC expression of PD-L1 on a large series of several human tumors to correctly define its staining in different tumor tissues. 相似文献
994.
Chiara De Notaris Peter Sørensen Henrik Bjarne Møller Radziah Wahid Jørgen Eriksen 《Nutrient Cycling in Agroecosystems》2018,112(3):355-368
Green manure mixtures including legumes and forbs can help to increase N availability in organic arable systems. Anaerobic digestion of green manures may provide ammonium rich digestate, which can be redistributed as fertilizer. The aim of this study was to investigate the effect of plant species composition, cutting strategy and anaerobic digestion on the N fertilizer replacement value (NFRV) of different green manures. Digestates obtained from silages of pure stand lucerne (four cuts/year) and a mixture including lucerne, grass and forbs (two or four cuts/year) were used to fertilize winter wheat (surface banding) and spring barley (injection). In general, NFRV was 46–173% higher in spring barley than winter wheat, due to the different application method and timing, which reflect the common practices in Denmark. NFRV of digestates were 25–63% higher than the corresponding silages, with the largest increase with the most fibrous material (mixture at two cuts/year). Total N concentration (DM based) in the silages largely explained NFRV of the digestates. To obtain NFRV above 60%, total N concentration of silage should exceed 3.5 g 100 g?1 DM, achievable with silages from four-cut strategies. Silages of plant materials with different composition and N content may be similar in terms of biomethane production, but the fertilizer value of the digestates varies considerably depending on total N concentration. 相似文献
995.
Andrea Padovan Sabrina Moret Renzo Bortolomeazzi Erica Moret Chiara Conchione Lanfranco S. Conte Ludger Brühl 《European Journal of Lipid Science and Technology》2020,122(5)
Formation of toxic alkylbenzenes, total polar compounds (%TPC) and degradation of tocochromanol are monitored. Analyses of the oil extracted from fried potatoes confirm the trend observed in the frying oil. The fresh oil has a TPC content of 3%, which increases with the frying time, exceeding the acceptable value (25%) after about 25 h for deep‐frying and 1.5 h for pan‐frying. During deep‐frying, total tocochromanol decreases to about half (25 mg per 100 g) of the initial value, pan‐frying shows faster, degradation (complete after 1.5 h). Toluene concentration increases with the frying time reaching a maximum, and afterwards gradually decreases. Except for butylbenzene during pan‐frying, pentylbenzene and butylbenzene concentration, increase with the frying time, but remain much lower than toluene. Practical Applications: This is the first systematic work comparing alkylbenzenes evolution under different frying conditions. Different from previous works, frying experiments are carried out following the indication of many European countries that recommend using temperature lower than 180 °C. The amount of alkylbenzenes assumed through a standard portion of fried potatoes (200 g) is assessed, which is relevant for evaluating dietary exposure to these contaminants. 相似文献
996.
Chiara Novara Francesco Petracca Alessandro Virga Paola Rivolo Sergio Ferrero Alessandro Chiolerio Francesco Geobaldo Samuele Porro Fabrizio Giorgis 《Nanoscale research letters》2014,9(1):527
Inkjet printing technique is exploited for the synthesis of Ag nanoparticles (NPs) patterned on electrochemically etched silicon-based substrates. The nanostructure morphology, here analyzed by scanning electron microscopy, is dictated by the ink composition and the printing parameters. Under suitable excitation conditions, resonant surface-enhanced Raman scattering (SERS) performed on such metal-dielectric nanostructures can approach single-molecule detection as recently demonstrated on silvered porous silicon synthesized by immersion plating.
PACS
78.67.Bf; 78.30.-j 相似文献997.
Carboxymethylinulin–Chitosan Nanoparticles for the Delivery of Antineoplastic Mitoxantrone 下载免费PDF全文
Dr. Daniele Merli Dr. Fabrizio Pivi Prof. Antonella Profumo Prof. Paolo Quadrelli Prof. Chiara Milanese Dr. Giulia Risi Prof. Livia Visai 《ChemMedChem》2016,11(21):2436-2444
Mitoxantrone (MTX) is an antineoplastic agent whose use is limited by serious side effects on non‐neoplastic cells. The aim of this study was the development of a new drug release system using an ionotropic gelation technique for microencapsulation of MTX in chitosan–carboxymethylinulin nanoparticles (CCInp), followed by evaluation of their cytotoxic effects on neoplastic MDA‐MB‐231 and non‐neoplastic NIH3T3 cell lines. The CCInp were prepared through a new reliable method for easy functionalization of both inulin and chitosan. Both unloaded and drug‐loaded nanoparticles were characterized by transmission electron microscopy (TEM) and dynamic light scattering (DLS) and showed a spherical morphology with an average hydrodynamic diameter between 40 and 80 nm. Both nanoparticles were stable and easily degraded by lysozyme. MTX‐loaded nanoparticles led to a greater mortality of MDA‐MB‐231 relative to free drug due to the ability of the nanoparticles to accumulate preferentially in neoplastic cells. The developed drug release system retains the ability to kill MDA‐MB‐231 cells in vitro, improving the survival of NIH3T3 cells. 相似文献
998.
Laura Righetti Josep Rubert Gianni Galaverna Silvia Folloni Roberto Ranieri Milena Stranska-Zachariasova Jana Hajslova Chiara Dall’Asta 《International journal of molecular sciences》2016,17(8)
Hulled, or ancient, wheats were the earliest domesticated wheats by mankind and the ancestors of current wheats. Their cultivation drastically decreased during the 1960s; however, the increasing demand for a healthy and equilibrated diet led to rediscovering these grains. Our aim was to use a non-targeted metabolomic approach to discriminate and characterize similarities and differences between ancient Triticum varieties. For this purpose, 77 hulled wheat samples from three different varieties were collected: Garfagnana T. turgidum var. dicoccum L. (emmer), ID331 T. monococcum L. (einkorn) and Rouquin T. spelta L. (spelt). The ultra high performance liquid chromatography coupled to high resolution tandem mass spectrometry (UHPLC-QTOF) metabolomics approach highlighted a pronounced sample clustering according to the wheat variety, with an excellent predictability (Q2), for all the models built. Fifteen metabolites were tentatively identified based on accurate masses, isotopic pattern, and product ion spectra. Among these, alkylresorcinols (ARs) were found to be significantly higher in spelt and emmer, showing different homologue composition. Furthermore, phosphatidylcholines (PC) and lysophosphatidylcholines (lysoPC) levels were higher in einkorn variety. The results obtained in this study confirmed the importance of ARs as markers to distinguish between Triticum species and revealed their values as cultivar markers, being not affected by the environmental influences. 相似文献
999.
Elisa Rambaldi Beatrice Lucchese Marcel Engels Maria Chiara Bignozzi 《International Journal of Applied Ceramic Technology》2019,16(2):625-637
The aim of this work is to evaluate the cleanability performances of lapped porcelain stoneware surfaces with and without protective treatments. The knowledge of the material cleanability is an important selection parameter in buying tiles. However, an objective basis for testing and assessing this property still is lacking. In this study, standardized and laboratory tests to evaluate the cleanability performance of lapped porcelain stoneware products have been carried out and compared. Cleanability tests were performed by applying two different soiling suspensions, optimized for tile surfaces and reproducing chemical and mechanical actions simulating the working conditions and traditional cleaning operations. Surface characteristics (microstructure, topography, roughness) were analyzed before and after cleanability tests. The results showed a good correlation between different behavior in terms of cleanability and the microscopic and topographic characteristics of lapped tile. Respect to international standardized tests specific for ceramic tiles, such as stains resistance test, the laboratory procedures to evaluate the surface cleanability are able to better show cleanability improvements of lapped tiles with protective treatments. 相似文献
1000.
Dr. Federica Sodano Dr. Elena Gazzano Dr. Aurore Fraix Prof. Barbara Rolando Dr. Loretta Lazzarato Dr. Marina Russo Dr. Marco Blangetti Prof. Chiara Riganti Prof. Roberta Fruttero Prof. Alberto Gasco Prof. Salvatore Sortino 《ChemMedChem》2018,13(1):87-96
The design, synthesis, spectroscopic and photochemical properties, and biological evaluation of a novel molecular hybrid that is able to deliver nitric oxide (NO) into mitochondria are reported. This molecular conjugate unites a tailored o‐CF3‐p‐nitroaniline chromophore, for photo‐regulated NO release, and a rhodamine moiety, for mitochondria targeting, in the same molecular skeleton via an alkyl spacer. A combination of steady‐state and time‐resolved spectroscopic and photochemical experiments demonstrate that the two chromogenic units preserve their individual photophysical and photochemical properties in the conjugate quite well. Irradiation with violet light triggers NO release from the nitroaniline moiety and photoionization in the rhodamine center, which also retains considerable fluorescence efficiency. The molecular hybrid preferentially accumulates in the mitochondria of A549 lung adenocarcinoma cells where it induces toxicity at a concentration of 1 μm , exclusively upon irradiation. Comparative experiments, carried out with ad‐hoc‐synthesized model compounds, suggest that the phototoxicity observed at such a low concentration is probably not due to NO itself, but rather to the formation of the highly reactive peroxynitrite that is generated from the reaction of NO with the superoxide anion. 相似文献