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581.
Guido de Guidi Giuseppina Bracchitta Alfio Catalfo 《Photochemistry and photobiology》2011,87(6):1214-1229
This review focuses on damage photosensitized by the fluoroquinolone (FQ) antibacterial drugs. Different models are employed to study biosubstrate photodamage mediated by FQs (organisms, cells, isolated biomolecules and super molecules). Being that the effect of environment (polarity of the medium, ions, pH, binding with bio‐molecules, etc.) is crucial in FQ photochemistry, photobiological reactions can be consequently dramatically influenced. Thus, the photosensitization processes induced by FQs are here discussed taking into account that such extensive and cross‐targeted pathological implications request an excursus covering photosensitization in systems of increasing molecular complexity. In vivo and in vitro evidences for photoallergy, phototoxicity, photomutagenesis and photocarcinogenesis mediated by FQs are discussed. 相似文献
582.
Carillo S Pieretti G Parrilli E Tutino ML Gemma S Molteni M Lanzetta R Parrilli M Corsaro MM 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(25):7053-7060
Pseudoalteromonas haloplanktis TAB 23 is a Gram-negative psychrophilic bacterium isolated from the Antarctic coastal sea. To survive in these conditions psychrophilic bacteria have evolved typical membrane lipids and "antifreeze" proteins to protect the inner side of the microorganism. As for Gram-negative bacteria, the outer membrane is mainly constituted by lipopoly- or lipooligosaccharides (LPS or LOS, respectively), which lean towards the external environment. Despite this, very little is known about the peculiarity of LPS from Gram-negative psychrophilic bacteria and what their role is in adaptation to cold temperature. Here we report the complete structure of the LOS from P. haloplanktis TAB 23. The lipid A was characterized by MALDI-TOF MS analysis and was tested in vitro showing a significant inhibitory effect on the LPS-induced pro-inflammatory cytokine production when added in culture with LPS from Escherichia coli. The product obtained after de-O-acylation of the LPS was analyzed by MALDI-TOF MS revealing the presence of several molecular species, differing in phosphorylation degree and oligosaccharide length. The oligosaccharide portion released after strong alkaline hydrolysis was purified by anion-exchange chromatography-pulsed amperometric detection (HPAEC-PAD) to give three main fractions, characterized by means of 2D NMR spectroscopy, which showed a very short highly phosphorylated saccharidic chain with the following general structure. α-Hepp3R,6R,4R'-(1→5)-α-Kdop4P-(2→6)-β-GlcpN4R-(1→6)-α-GlcpN1P (R=-H(2)PO(3) or -H; R'=α-Galp-(1→4)-β-Galp-(1→ or H-). 相似文献
583.
Giuseppina Raffaini Fabio Ganazzoli 《Journal of inclusion phenomena and macrocyclic chemistry》2013,76(1-2):213-221
This paper reports a molecular modeling study of complex formation and aggregation behavior of a supramolecular system comprising three different moieties forming two distinct molecules. One molecule is a phenol derivative of porphyrin conjugated to a macrocyclic oligosaccharide, β-cyclodextrin (β-CD), and the other is 1-adamantanol (ADM). The inclusion complex of the latter molecule with the porphyrin–β-cyclodextrin (β-CD) conjugate, and the dimeric aggregates of the conjugate both in the presence and in the absence of the guest are investigated through molecular mechanics and molecular dynamics methods in vacuo, since the systems are scarcely soluble in polar solvents. In this way, we can find the most likely geometry of the complexes or aggregates and characterize the competitive inclusion behavior of ADM and of a porphyrin phenol within the β-CD cavity in terms of the various energy contributions stabilizing the resulting aggregates and/or inclusion complexes. 相似文献
584.
Federica Bianchi Giuseppina Basini Stefano Grolli Virna Conti Francesco Bianchi Francesca Grasselli Maria Careri Roberto Ramoni 《Analytical and bioanalytical chemistry》2013,405(2-3):1067-1075
Odorant binding protein (OBP) is a multi-functional scavenger for small hydrophobic molecules dissolved in the mucus lining the nasal epithelia of mammals, characterized by broad ligand binding specificity towards a large number of structurally unrelated natural and synthetic molecules of different chemical classes. Here, we demonstrate for the first time the application of OBP as the active element of an innovative filtering matrix for the removal of environmental pollutants such as triazine herbicides from water samples. The filtering device, obtained by coupling histidine-tagged bovine OBP to a nickel nitrilotriacetic acid (Ni-NTA) agarose resin, was characterized in terms of retention capacity for the herbicides atrazine, simazine, and propazine. Analysis of these herbicides at trace levels with solid-phase microextraction followed by gas chromatography–mass spectrometry using the selected ion monitoring mode proved the capabilities of the proposed device for the decontamination of surface and groundwater samples in the 0.2–2,300 μg/L concentration range, obtaining a reduction in the triazine content greater than 97 %, thus suggesting its possible use for the potabilization of water. Figure
Tridimensional structure of bOBP with AMA inside the cavity 相似文献
585.
Fedora Grande Francesca Giordano Maria Antonietta Occhiuzzi Carmine Rocca Giuseppina Ioele Michele De Luca Gaetano Ragno Maria Luisa Panno Bruno Rizzuti Antonio Garofalo 《Molecules (Basel, Switzerland)》2021,26(13)
The antitumor activity of certain anti-inflammatory drugs is often attributed to an indirect effect based on the inhibition of COX enzymes. In the case of anti-inflammatory prodrugs, this property could be attributed to the parent molecules with mechanism other than COX inhibition, particularly through formulations capable of slowing down their metabolic conversion. In this work, a pilot docking study aimed at comparing the interaction of two prodrugs, nabumetone (NB) and its tricyclic analog 7-methoxy-2,3-dihydro-1H-cyclopenta[b]naphthalen-1-one (MC), and their common active metabolite 6-methoxy-2-naphthylacetic acid (MNA) with the COX binding site, was carried out. Cytotoxicity, cytofluorimetry, and protein expression assays on prodrugs were also performed to assess their potential as antiproliferative agents that could help hypothesize an effective use as anticancer therapeutics. Encouraging results suggest that the studied compounds could act not only as precursors of the anti-inflammatory metabolite, but also as direct antiproliferative agents. 相似文献
586.
In a projective plane $PG(2,\mathbb K )$ over an algebraically closed field $\mathbb K $ of characteristic $p\ge 0$ , let $\Omega $ be a pointset of size $n$ with $5\le n \le 9$ . The coset intersection problem relative to $\Omega $ is to determine the family $\mathbf F$ of irreducible cubics in $PG(2,\mathbb K )$ for which $\Omega $ is a common coset of a subgroup of the additive group $(\mathcal F ,+)$ for every $\mathcal F \in \mathbf F$ . In this paper, a complete solution of this problem is given. 相似文献
587.
Giuseppina Orlandini Sonia Bacca Nir Barnea Gaute Hagen Mirko Miorelli Thomas Papenbrock 《Few-Body Systems》2014,55(8-10):907-911
Here we summarize how the LIT and CC methods can be coupled, in order to allow for ab initio calculations of reactions in medium mass nuclei. Results on 16O are reviewed and preliminary calculations on 40Ca are presented. 相似文献
588.
An advanced and powerful chemometric approach is proposed for the analysis of incomplete multiset data obtained by fusion of hyphenated liquid chromatographic DAD/MS data with UV spectrophotometric data from acid–base titration and kinetic degradation experiments. Column- and row-wise augmented data blocks were combined and simultaneously processed by means of a new version of the multivariate curve resolution-alternating least squares (MCR-ALS) technique, including the simultaneous analysis of incomplete multiset data from different instrumental techniques. The proposed procedure was applied to the detailed study of the kinetic photodegradation process of the amiloride (AML) drug. All chemical species involved in the degradation and equilibrium reactions were resolved and the pH dependent kinetic pathway described. 相似文献
589.
Santagati NA Salerno L Attaguile G Savoca F Ronsisvalle G 《Journal of chromatographic science》2008,46(2):150-156
A simple high-performance liquid chromatography method using a diode array detector (DAD) is developed for the simultaneous analysis of five major catechins: (+)-catechin (C), (-)-epicatechin (EC), (-)-gallocatechin (GCT), (-)-epigallocatechin (EGC), (-)-epigallocatechin gallate (EGCG), and the phenolic plant metabolites gallic acid (GA) and rutin (RT) in lyophilized extracts of Cistus species. The optimal analytical conditions are investigated to obtain the best resolution and the highest UV sensitivity for the quantitative detection of catechins. The optimized conditions (acetonitrile-phosphate buffer 50mM, pH 2.5, gradient elution system on a C(18) reversed-phase column with a flow rate of 1 mL/min and UV absorbance at 210 nm) allowed a specific and repeatable separation of the studied analytes to be achieved. All compounds are successfully separated within 32 min. Calibration curves are linear in the 2-50 microg/mL range for GCT, C, and EGCG and in the 5-50 microg/mL range for GA, EGC, EC, and RT. The limit of detection values ranged from 0.24 to 0.74 microg/mL. The limit of quantitation limit values ranged from 0.77 to 1.94 microg/mL. The validated method is applied to the determination of the specific phytochemical markers GA, GCT, C, and RT in Cistus incanus and Cistus monspeliensis lyophilised extracts. The recovery values ranged between 78.7% and 98.2%. The described HPLC method appears suitable for the differentiation and determination of the most common catechins together with the glycoside rutin and the phenolic compound gallic acid and can be considered an effective and alternative procedure for the analyses of this important class of natural compounds. 相似文献
590.
Yuhao Yang Seyedesahar Miraghaee Renee Pace Dr. Teruo Umemoto Prof. Gerald B. Hammond 《Angewandte Chemie (International ed. in English)》2023,62(32):e202306095
A novel, air and thermally stable, yet highly reactive trifluoromethylthiolating reagent, CF3SO2SCF3 ( 1 ), was prepared easily in one step from commercially inexpensive CF3SO2Na and Tf2O. 1 is a highly versatile and atom-efficient reagent that can generate one equivalent of CF3S + , two equivalents of CF3S−, or a combination of CF3S⋅/CF3⋅ species. Many high-yielding CF3S reactions of C, O, S, and N-nucleophiles were achieved, including the simple-step preparations of many reported CF3S reagents. 1 delivered a hitherto hard-to-synthesize ArOSCF3 that was followed by a novel CF3SII-rearrangement. Through Cu or TDAE/Ph3P combinations, 1 generated two equivalents of CF3S anion species, and the photo-catalyzed reactions of alkenes with 1 provided CF3/CF3S-containing products in high atom-efficiency. 相似文献