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971.
Rafael Gozalbes Silvia Mosulén Rodrigo J. Carbajo Antonio Pineda-Lucena 《Journal of computer-aided molecular design》2009,23(8):555-569
A combined strategy based on the development of pharmacophore hypotheses and NMR approaches is reported for the identification
of novel inhibitors of heparanase, a key enzyme involved in tumor metastasis through the remodeling of the subepithelial and
subendothelial basement membranes, resulting in the dissemination of metastatic cancer cells. Several pharmacophore hypotheses
were initially developed from the most active heparanase inhibitors known to date and, after their application to a pool of
27 known heparanase inhibitors and a database of 1,120 compounds approved by the FDA, a four-point pharmacophore model was
selected as the most predictive. This model was subsequently applied to a database of 686 chemical fragments, and a subset
of 100 fragments accomplishing completely or partially the four-point model was selected to perform nuclear magnetic resonance
experiments to validate the hypothesis. The experimental studies confirmed the reliability of our pharmacophore model, its
applicability to in silico databases in order to reduce the number of compounds to be experimentally screened, and the possibility
of generating fragment libraries enriched in heparanase inhibitors.
Rafael Gozalbes and Silvia Mosulén contributed equally to this work. 相似文献
972.
Urska Lavrencic Stangar Alessandro Sassi Alfonso Venzo Andrea Zattin Boštjan Japelj Boris Orel Silvia Gross 《Journal of Sol-Gel Science and Technology》2009,49(3):329-335
The sol–gel reactions of the two methacrylate-modified silanes methacryloxymethyltriethoxysilane (MAMTES) and methacryloxypropyltrimethoxysilane
(MAPTMS) were followed by using two independent time-resolved spectroscopic methods, viz., IR ATR and NMR with the aim to
optimise their pre-hydrolysis times and consequently their use as precursors for hybrid materials. Time resolved measurements
were carried out on the two systems under sol–gel conditions. Whereas the hydrolysis of both siloxanes is very fast, condensation
proceeds gradually and is not completely finished within 5 h. 相似文献
973.
Nicola Marchi Qingshan Teng Minh T Nguyen Linda Franic Nirav K Desai Thomas Masaryk Peter Rasmussen Silvia Trasciatti Damir Janigro 《BMC neuroscience》2010,11(1):34
Background
Stem cells or immune cells targeting the central nervous system (CNS) bear significant promises for patients affected by CNS disorders. Brain or spinal cord delivery of therapeutic cells is limited by the blood-brain barrier (BBB) which remains one of the recognized rate-limiting steps. Osmotic BBB disruption (BBBD) has been shown to improve small molecule chemotherapy for brain tumors, but successful delivery of cells in conjunction with BBBD has never been reported. 相似文献974.
Silvia Burlina Cristina Banfi Maura Brioschi Silvia Visentin Maria Grazia Dalfr Pietro Traldi Annunziata Lapolla 《Journal of mass spectrometry : JMS》2019,54(4):359-365
In pregnancy complicated by gestational diabetes mellitus (GDM), the human placenta shows several pathological functional and structural changes, but the extent to which maternal glycemic control contributes to placental abnormalities remains unclear. The aim of this study was to profile and compare the proteome of placentas from healthy pregnant women and those with GDM, to investigate the placenta‐specific protein composition and possible changes of its function in presence of GDM. Quantitative proteomic analysis, based on LC‐MSE approach, revealed that higher (approximately 15% increase) levels of galectin 1 and collagen alpha‐1 XIV chain (although the difference regarding the latter was at the limit of significance) were present in GDM samples, while heat shock 70 kDa protein 1A/1B was less abundant in GDM placental tissue. These data seem to indicate that GDM, when well controlled, did not markedly affect the placental proteome. 相似文献
975.
Leandro Javier Salvo Lorenzo Coiana Cecilia Dobrecky Valeria Tripodi Sabrina Flor Silvia Lucangioli 《Electrophoresis》2019,40(12-13):1719-1721
A simple and highly sensitive CE–UV method was applied in the determination of l ‐ctrulline, which was developed from an oral formulation for pediatric use. The novel method was based on the analysis of l ‐citrulline for direct ultraviolet detection at 198 nm. The BGE consisted of 10 mM sodium tetraborate and 50 mM SDS at pH 9, and the electrophoretic parameters were optimized. The method was validated in terms of specificity, linearity, LOD, LOQ, precision, accuracy, and robustness. The LOD and LOQ obtained were 1.36 and 4.54 μg/mL, respectively. In addition, the method offers higher sensitivity and specificity compared with the results obtained from HPLC method using UV‐detectors, in which l‐ citrulline needs to be derivatizated. Furthermore, low cost and simplicity of the system allowed the rapid and simple quantitation of l‐ citrulline in the oral formulation for quality control and stability indicated method. 相似文献
976.
977.
Marion Kieffer Ana M. Garcia Cally J. E. Haynes Slavko Kralj Daniel Iglesias Jonathan R. Nitschke Silvia Marchesan 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(24):8066-8070
An unreported d,l ‐tripeptide self‐assembled into gels that embedded FeII4L4 metal–organic cages to form materials that were characterized by TEM, EDX, Raman spectroscopy, rheometry, UV/Vis and NMR spectroscopy, and circular dichroism. The cage type and concentration modulated gel viscoelasticity, and thus the diffusion rate of molecular guests through the nanostructured matrix, as gauged by 19F and 1H NMR spectroscopy. When two different cages were added to spatially separated gel layers, the gel–cage composite material enabled the spatial segregation of a mixture of guests that diffused into the gel. Each cage selectively encapsulated its preferred guest during diffusion. We thus present a new strategy for using nested supramolecular interactions to enable the separation of small molecules. 相似文献
978.
Francesco Zinna Silvia Voci Lorenzo Arrico Elodie Brun Alexandre Homberg Laurent Bouffier Tiziana Funaioli Jrme Lacour Neso Sojic Lorenzo DiBari 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(21):7026-7030
The first observation of circular polarization of electrochemiluminescence (ECL) from a purely organic derivative is reported. A bispyrene scaffold mounted on a constrained polyether macrocycle displaying intense excimer fluorescence and highly circularly‐polarized (CP) photoluminescence has been selected for this purpose. The compound displays an ECL dissymmetry factor of about |8×10?3|, which is in good agreement with the corresponding photoluminescence value. This observation is the first step towards the molecular engineering of tailored dyes that can act as both ECL and CP‐ECL reporters for (bio)analysis by bringing a new level of information when dealing with chiral environments. Additionally, it provides an extra dimension to the ECL phenomenon and opens the way to chiral detection and discrimination. 相似文献
979.
Juan Zinczuk Ana Estela Ledesma Silvia Antonia Brandán Oscar Enrique Piro Juan Jesús López‐González Aída Ben Altabef 《Journal of Physical Organic Chemistry》2009,22(12):1166-1177
In this study 2‐(2′‐furyl)‐4,5‐1H‐dihydroimidazole (1) was prepared and then characterized by infrared, Raman, and multidimensional nuclear magnetic resonance (NMR) spectroscopies. The crystal and molecular structures of 1 were determined by X‐ray diffraction methods. The density functional theory (DFT) and second‐order Møller–Plesset theory (MP2) with Pople's basis set show that there are two conformers for the title molecule that have been theoretically determined in the gas phase, and that only one of them, conformer I, is present in the solid phase. NMR spectra observed for 1 were successfully compared with the calculated chemical shifts at the B3LYP/6‐311++G** level theorized for this conformer. The harmonic vibrational frequencies for the optimized geometry of the latter conformer were calculated at the B3LYP/6‐311++G** level in the approximation of the isolated molecule. For a complete assignment of the IR and Raman spectra in the solid phase of 1 , DFT calculations were combined with Pulay´s scaled quantum mechanics force field (SQMFF) methodology to fit the theoretical frequency values to the experimental ones. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
980.
Maria Luisa Astolfi Marcelo Enrique Conti Martina Ristorini Maria Agostina Frezzini Marco Papi Lorenzo Massimi Silvia Canepari 《Molecules (Basel, Switzerland)》2021,26(16)
Bees and their products are useful bioindicators of anthropogenic activities and could overcome the deficiencies of air quality networks. Among the environmental contaminants, mercury (Hg) is a toxic metal that can accumulate in living organisms. The first aim of this study was to develop a simple analytical method to determine Hg in small mass samples of bees and beehive products by cold vapor atomic fluorescence spectrometry. The proposed method was optimized for about 0.02 g bee, pollen, propolis, and royal jelly, 0.05 g beeswax and honey, or 0.1 g honeydew with 0.5 mL HCl, 0.2 mL HNO3, and 0.1 mL H2O2 in a water bath (95 °C, 30 min); samples were made up to a final volume of 5 mL deionized water. The method limits sample manipulation and the reagent mixture volume used. Detection limits were lower than 3 µg kg−1 for a sample mass of 0.02 g, and recoveries and precision were within 20% of the expected value and less than 10%, respectively, for many matrices. The second aim of the present study was to evaluate the proposed method’s performances on real samples collected in six areas of the Lazio region in Italy. 相似文献