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71.
Giorgio Gianini Morbioli Thiago Mazzu-Nascimento Adriano Aquino Cesar Cervantes Emanuel Carrilho 《Analytica chimica acta》2016
We present here a critical review covering conventional analytical tools of recombinant drug analysis and discuss their evolution towards miniaturized systems foreseeing a possible unique recombinant drug-on-a-chip device. Recombinant protein drugs and/or pro-drug analysis require sensitive and reproducible analytical techniques for quality control to ensure safety and efficacy of drugs according to regulatory agencies. The versatility of miniaturized systems combined with their low-cost could become a major trend in recombinant drugs and bioprocess analysis. Miniaturized systems are capable of performing conventional analytical and proteomic tasks, allowing for interfaces with other powerful techniques, such as mass spectrometry. Microdevices can be applied during the different stages of recombinant drug processing, such as gene isolation, DNA amplification, cell culture, protein expression, protein separation, and analysis. In addition, organs-on-chips have appeared as a viable alternative to testing biodrug pharmacokinetics and pharmacodynamics, demonstrating the capabilities of the miniaturized systems. The integration of individual established microfluidic operations and analytical tools in a single device is a challenge to be overcome to achieve a unique recombinant drug-on-a-chip device. 相似文献
72.
73.
Regli L Bordiga S Busco C Prestipino C Ugliengo P Zecchina A Lamberti C 《Journal of the American Chemical Society》2007,129(40):12131-12140
Insertion of B atoms into an Al-free zeolitic framework with CHA topology results in the formation of B-SSZ-13 zeotype with Si/B = 11. B K-edge NEXAFS testifies that B forms [B(OSi)4] units in a Td-like geometry (sp3-hybridized B atoms). According to B K-edge NEXAFS and IR, template burning results in the formation of [B(OSi)3] units in a D3h-like geometry (sp2-hybridized B atoms) with a break of a B-O-Si bond and the formation of a Si-OH group. The activated material contains B(III) Lewis acid centers able to specifically coordinate bases like NH3. Such [B(OSi)3] units are reactive toward ammonia, resulting in the formation of B-NH2 surface functionality inside the pores of B-SSZ-13 already under mild conditions, i.e., 35 mbar of NH3 at 373 K for 30 min and without crystallinity degradation. A minor fraction of Si-NH2 cannot be excluded owing to the presence of two IR doublets at 3500 and 3430 cm-1 and at 1600 and 1550 cm-1. Ab initio B3LYP/6-31+G(d,p) calculations on a cluster model, supported by a single-point MP2 on B3LYP/6-31+G(D,P) optimized structures, found the break by NH3 of a B-O-Si bond of the [B(OSi)3] unit with formation of [SiOH] and [H2N-B(OSi)2] species to be energetically favored. Comparison between experimental and computed frequency shifts shows them to be in semiquantitative agreement. The high stability of the B-NH2 surface functionality is probed by N K-edge NEXAFS spectra collected under UHV conditions. These findings can open a new route in the preparation of shape selective solid basic catalysts. 相似文献
74.
Carlo Lamberti Carmelo Prestipino Francesca Bonino Luciana Capello Silvia Bordiga Giuseppe Spoto Adriano Zecchina Sofia Diaz Moreno Barbara Cremaschi Marco Garilli Andrea Marsella Diego Carmello Sandro Vidotto Giuseppe Leofanti 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2002,114(13):2447-2450
75.
Nilufar Z. Mamadalieva Fadia S. Youssef Hidayat Hussain Gokhan Zengin Adriano Mollica Nawal M. Al Musayeib Mohamed L. Ashour Bernhard Westermann Ludger A. Wessjohann 《Molecules (Basel, Switzerland)》2021,26(21)
The antioxidant and enzyme inhibitory potential of fifteen cycloartane-type triterpenes’ potentials were investigated using different assays. In the phosphomolybdenum method, cycloalpioside D (6) (4.05 mmol TEs/g) showed the highest activity. In 1,1-diphenyl-2-picrylhydrazyl (DPPH*) radical and 2,2′-azino-bis(3-ethylbenzothiazoline)-6-sulfonic acid (ABTS) cation radical scavenging assays, cycloorbicoside A-7-monoacetate (2) (5.03 mg TE/g) and cycloorbicoside B (10) (10.60 mg TE/g) displayed the highest activities, respectively. Oleanolic acid (14) (51.45 mg TE/g) and 3-O-β-d-xylopyranoside-(23R,24S)-16β,23;16α,24-diepoxycycloart-25(26)-en-3β,7β-diol 7-monoacetate (4) (13.25 mg TE/g) revealed the highest reducing power in cupric ion-reducing activity (CUPRAC) and ferric-reducing antioxidant power (FRAP) assays, respectively. In metal-chelating activity on ferrous ions, compound 2 displayed the highest activity estimated by 41.00 mg EDTAE/g (EDTA equivalents/g). The tested triterpenes showed promising AChE and BChE inhibitory potential with 3-O-β-d-xylopyranoside-(23R,24S)-16β,23;16α,24-diepoxycycloart-25(26)-en-3β,7β-diol 2′,3′,4′,7-tetraacetate (3), exhibiting the highest inhibitory activity as estimated from 5.64 and 5.19 mg GALAE/g (galantamine equivalent/g), respectively. Compound 2 displayed the most potent tyrosinase inhibitory activity (113.24 mg KAE/g (mg kojic acid equivalent/g)). Regarding α-amylase and α-glucosidase inhibition, 3-O-β-d-xylopyranoside-(23R,24S)-16β,23;16α,24-diepoxycycloart-25(26)-en-3β,7β-diol (5) (0.55 mmol ACAE/g) and compound 3 (25.18 mmol ACAE/g) exerted the highest activities, respectively. In silico studies focused on compounds 2, 6, and 7 as inhibitors of tyrosinase revealed that compound 2 displayed a good ranking score (−7.069 kcal/mole) and also that the ΔG free-binding energy was the highest among the three selected compounds. From the ADMET/TOPKAT prediction, it can be concluded that compounds 4 and 5 displayed the best pharmacokinetic and pharmacodynamic behavior, with considerable activity in most of the examined assays. 相似文献
76.
Drug design is a process driven by innovation and technological breakthroughs involving a combination of advanced experimental
and computational methods. A broad variety of medicinal chemistry approaches can be used for the identification of hits, generation
of leads, as well as to accelerate the optimization of leads into drug candidates. Quantitative structure–activity relationship
(QSAR) methods are among the most important strategies that can be applied for the successful design of small molecule modulators
having clinical utility. Hologram QSAR (HQSAR) is a modern 2D fragment-based QSAR method that employs specialized molecular
fingerprints. HQSAR can be applied to large data sets of compounds, as well as traditional-size sets, being a versatile tool
in drug design. The HQSAR approach has evolved from a classical use in the generation of standard QSAR models for data correlation
and prediction into advanced drug design tools for virtual screening and pharmacokinetic property prediction. This paper provides
a brief perspective on the evolution and current status of HQSAR, highlighting present challenges and new opportunities in
drug design. 相似文献
77.
Production of Cellulolytic Enzymes by <Emphasis Type="Italic">Aspergillus phoenicis</Emphasis> in Grape Waste using Response Surface Methodology 总被引:1,自引:0,他引:1
Dedavid e Silva LA Lopes FC Silveira ST Brandelli A 《Applied biochemistry and biotechnology》2009,152(2):295-305
The production of cellulolytic enzymes by the fungus Aspergillus phoenicis was investigated. Grape waste from the winemaking industry was chosen as the growth substrate among several agro-industrial
byproducts. A 2 × 2 central composite design was performed, utilizing the amount of grape waste and peptone as independent
variables. The fungus was cultivated in submerged fermentation at 30 °C and 120 rpm for 120 h, and the activities of total
cellulases, endoglucanases, and β-glucosidases were measured. Total cellulases were positively influenced by the linear increase
of peptone concentration and decrease at axial concentrations of grape waste and peptone. Maximum activity of endoglucanase
was observed by a linear increase of both grape waste and peptone concentrations. Concentrations of grape waste between 5
and 15 g/L had a positive effect on the production of β-glucosidase; peptone had no significant effects. The optimum production
of the three cellulolytic activities was observed at values near the central point. A. phoenicis has the potential for the production of cellulases utilizing grape waste as the growth substrate. 相似文献
78.
An extraction method based on matrix solid-phase dispersion was developed to determine carbofuran, pyrimethanil and tetraconazole in banana using gas chromatography–mass spectrometry. The best results were obtained using 2.0 g of banana, 1.0 g of silica as dispersant sorbent and n-hexane:ethyl acetate (1:4, v/v) as eluting solvent. The method was validated using banana samples fortified with pesticides at different concentration levels (0.05–2.0 mg kg?1). Average recoveries (four replicates) ranged from 68 to 111%, with relative standard deviations between 6.6 and 20.5%. Detection and quantification limits for banana ranged from 0.02 to 0.05 and 0.05 to 0.10 mg kg?1, respectively. 相似文献
79.
Phabyanno Rodrigues Lima Paulo Rogério Barbosa de Miranda Adriano Bof de Oliveira Marília Oliveira Fonseca Goulart Lauro Tatsuo Kubota 《Electroanalysis》2009,21(21):2311-2320
The present work explores, for the first time, the electrocatalytic oxidation of ascorbic acid (AscH2) and its determination in the presence of uric acid (UA) on the in situ activated 4‐nitrophthalonitrile modified carbon paste electrode. The kinetic constant κ for the catalytic reaction for the electrocatalytic oxidation of ascorbic acid, evaluated by cyclic voltammetry, chronoamperometry and RDE voltammetry provided values around 106 L mol?1 s?1. The sensor provided a linear response range for AscH2 and UA from 5.0 up to 120.0 μmol L?1 with detection limits of 1.6 μmol L?1and 1.3 μmol L?1, respectively. The sensor was applied for the simultaneous determination of AscH2 and UA in urine samples and the average recoveries for these samples were 99.8 (±3.1)% and 99.9 (±2.1)%, respectively . 相似文献
80.
NO-releasing zeolites and their antithrombotic properties 总被引:1,自引:0,他引:1
Wheatley PS Butler AR Crane MS Fox S Xiao B Rossi AG Megson IL Morris RE 《Journal of the American Chemical Society》2006,128(2):502-509
Transition metal-exchanged zeolite-A adsorbs and stores nitric oxide in relatively high capacity (up to 1 mmol of NO/g of zeolite). The stored NO is released on contact with an aqueous environment under biologically relevant conditions of temperature and pH. The release of the NO can be tuned by altering the chemical composition of the zeolite, by controlling the amount of water contacting the zeolite, and by blending the zeolite with different polymers. The high capacity of zeolite for NO makes it extremely attractive for use in biological and medical applications, and our experiments indicate that the NO released from Co-exchanged zeolite-A inhibits platelet aggregation and adhesion of human platelets in vitro. 相似文献