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排序方式: 共有321条查询结果,搜索用时 15 毫秒
311.
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
312.
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
313.
Alla P. Toropova Andrey A. Toropov Emilio Benfenati Giuseppina Gini Danuta Leszczynska Jerzy Leszczynski 《Molecular diversity》2011,15(1):249-256
Quantitative structure–property relationships (QSPRs) between the molecular structure of [C60] and [C70] fullerene derivatives and their solubility in chlorobenzene (mg/mL) have been established by means of CORAL (CORrelations
And Logic) freeware. The CORAL models are based on representation of the molecular structure by simplified molecular input
line entry system (SMILES). Three random splits into the training and the external validation sets have been examined. The
ranges of statistical characteristics of these models are as follows: n = 18, r
2 = 0.748–0.815, s = 15.1 –17.5 (mg/mL), F = 47–71 (training set); n = 9, r
2 = 0.806–0.936, s = 12.5–17.5 (mg/mL), F = 29–103 (validation set). 相似文献
314.
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
315.
In this paper we prove existence and comparison results for nonlinear parabolic equations which are modeled on the problem
$\left\{{ll}{u_t - {\rm div}\,\left(\frac{1}{(1+|u|)^{\alpha}}|Du|^{p-2}Du\right)
=f\quad\hskip 2pt \,\,{\rm in}\,\Omega\times(0,T),}\\
{u=0\qquad\qquad\qquad\qquad\quad\quad\qquad{\rm
on}\,\partial\Omega\times(0,T),}\\
{u(x,0)=u_0(x)\quad\qquad\qquad\qquad\qquad{\rm
in}\,\Omega,}\right.$\left\{\begin{array}{ll}{u_t - {\rm div}\,\left(\frac{1}{(1+|u|)^{\alpha}}|Du|^{p-2}Du\right)
=f\quad\hskip 2pt \,\,{\rm in}\,\Omega\times(0,T),}\\
{u=0\qquad\qquad\qquad\qquad\quad\quad\qquad{\rm
on}\,\partial\Omega\times(0,T),}\\
{u(x,0)=u_0(x)\quad\qquad\qquad\qquad\qquad{\rm
in}\,\Omega,}\end{array}\right. 相似文献
316.
Giuseppina Biscari Yanmiao Fan Faridah Namata Calogero Fiorica Michael Malkoch Fabio Salvatore Palumbo Giovanna Pitarresi 《Macromolecular bioscience》2023,23(12):2300224
Treating wound infections is a difficult task ever since pathogenic bacteria started to develop resistance to common antibiotics. The present study develops hybrid hydrogels based on the formation of a polyelectrolyte complex between the anionic charges of dopamine-functionalized Gellan Gum (GG-DA) and the cationic moieties of the TMP-G2-alanine dendrimer. The hydrogels thus obtained can be doubly crosslinked with CaCl2, obtaining solid hydrogels. Or, by oxidizing dopamine to GG-DA, possibly causing further interactions such as Schiff Base and Michael addition to take place, hydrogels called injectables can be obtained. The latter have shear-thinning and self-healing properties (efficiency up to 100%). Human dermal fibroblasts (HDF), human epidermal keratinocytes (HaCaT), and mouse monocyte cells (RAW 264.7), after incubation with hydrogels, in most cases show cell viability up to 100%. Hydrogels exhibit adhesive behavior on various substrates, including porcine skin. At the same time, the dendrimer serves to crosslink the hydrogels and endows them with excellent broad-spectrum microbial eradication activity within four hours, evaluated using Staphylococcus aureus 2569 and Escherichia coli 178. Using the same GG-DA/TMP-G2-alanine ratios hybrid hydrogels with tunable properties and potential for wound dressing applications can be produced. 相似文献
317.
In high-throughput proteomics, the bottom-up approach has become a widely used method for the identification of proteins that is based on tryptic peptide MS/MS analysis. Separation methodologies that use IEF of tryptic peptides have recently been introduced and provide an extra dimension of peptide separation. In addition to its great fractionation capability, tryptic peptide prefractionation by IEF can also increase the protein identification success. The pI information of the peptide gained can be successfully used in a post-database search filtering step. We introduce a filtering algorithm that is based on the comparison of the experimental and theoretical pI's to validate peptide identifications by MS/MS data search engines. 相似文献
318.
Giuseppina Raffaini Fabio Ganazzoli 《Journal of inclusion phenomena and macrocyclic chemistry》2007,57(1-4):683-688
A general method is proposed to model the behavior of cyclodextrins (CDs) and of their inclusion compounds through energy
minimizations and molecular dynamics (MD) simulations at a constant temperature. In this way, the formation of a host–guest
compound is obtained starting from many trial geometries with the guest outside the CD cavity without any a priori assumption.
The MD simulation results are analyzed through two functions: (i) the similarity maps of the root-mean-square distances between instantaneous conformations found in the MD runs to recognize
different families of conformers; (ii) the pair distribution function PDF, yielding the probability density of finding appropriate atom pairs as a function of
their distance at equilibrium. As an example, the inclusion compound formed by β-CD and (−)-menthol-β-d-glucoside is investigated. The lowest-energy inclusion compound is in good agreement with the results of single-crystal X-ray
analysis, while at room temperature the MD runs show a closely similar arrangement with thermal fluctuations. In this case,
the PDF between diagnostic hydrogen atoms of β-CD and of the guest molecule are fully consistent with the experimental NOE
results obtained from NMR measurements in solution. 相似文献
319.
Giuseppina Costabile Giuseppe Della Pepa Claudia Vetrani Paola Vitaglione Ettore Griffo Rosalba Giacco Marilena Vitale Dominic Salamone Angela Albarosa Rivellese Giovanni Annuzzi Lutgarda Bozzetto 《Molecules (Basel, Switzerland)》2021,26(11)
Interest has arisen on the anti-inflammatory action of dietary components, including long-chain n-3 fatty acids (LCn3) and polyphenols (PP). The aim of this study was to evaluate the effects of diets rich in PP and oily fish (high-LCn3 diets) on markers of subclinical inflammation and growth factors in people at high cardiometabolic risk. Individuals with high waist circumference and one more component of metabolic syndrome were randomized to one of the following isoenergetic diets: low LCn3&PP, high LCn3, high PP, high LCn3&PP. Before and after 8 weeks, fasting and postprandial plasma concentrations of hs-CRP and fasting serum concentrations of IL-1β, IL-4, IL-6, IL-10, IL-17, INF-γ, TNF-α, FGF, VEGF, PDGF-ββ, G-CSF, and GM-CSF were determined. An oily fish diet reduced fasting plasma hs-CRP (1.28 ± 12.0, −12.5 ± 6.9, 22.5 ± 33.6, −12.2 ± 11.9; 8-week percent change, Mean ± SEM; low LCn3&PP, high LCn3, high PP, high LCn3&PP group, respectively), postprandial 6h-AUC hs-CRP (4.6 ± 16.3, −18.2 ± 7.2, 26.9 ± 35.1, −11.5 ± 11.8, 8-week percent change) and fasting IL-6 (20.8 ± 18.7, −2.44 ± 12.4, 28.1 ± 17.4, −9.6 ± 10.2), IL-17 (2.40 ± 4.9, −13.3 ± 4.9, 3.8 ± 4.43, −11.5 ± 4.7), and VEGF (−5.7 ± 5.8, −5.6 ± 7.5, 3.5 ± 5.8, −11.1 ± 5.5) (8-week percent change; p < 0.05 for LCn3 effect for all; no significant effect for PP; 2-factor ANOVA). An oily fish diet improved subclinical inflammation, while no significant effect was observed for dietary polyphenols. 相似文献
320.
Andrey A. Toropov Alla P. Toropova Ivan Raska Jr. Emilio Benfenati Giuseppina Gini 《Structural chemistry》2012,23(6):1891-1904
The representation of the molecular structure by a system (sequence) of amino acids has been used to establish quantitative structure–property/activity relationships (QSPR/QSAR) which can be used for (i) bioactivities of epitope-peptides, (ii) antibacterial potencies of polypeptides, and (iii) the binding affinity of peptides that bind to the class I major histocompatibility complex molecule HLA-A*0201. The representation of the peptide structure has been done via 1-letter abbreviations of amino acids, i.e., A (alanine), C (cysteine), D (aspartic), etc. This approach allows classifying amino acids according to their function in a biochemical process (promoters of increase or decrease of an endpoint). 相似文献
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