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Malva sylvestris L. extract suppresses desferrioxamine‐induced PGE2 and PGD2 release in differentiated U937 cells: the development and validation of an LC‐MS/MS method for prostaglandin quantification 下载免费PDF全文
Cleverson Antonio Ferreira Martins Almeriane Maria Weffort‐Santos João Cleverson Gasparetto Angela Cristina Leal Badaró Trindade Michel Fleith Otuki Roberto Pontarolo 《Biomedical chromatography : BMC》2014,28(7):986-993
Malva sylvestris is a species used worldwide as an alternative to anti‐inflammatory therapies; however, its mechanism of action remains unknown. In this paper, the anti‐inflammatory effects of M. sylvestris alcoholic extracts were evaluated by measuring the pro‐inflammatory mediators PGE2 and PGD2 in desferrioxamine‐stimulated phorbol 12‐myristate 13‐acetate‐differentiated U937 cells. An HPLC‐DAD fingerprint of the M. sylvestris extract was performed and caffeic acid, ferulic acid and scopoletin were identified and quantified. An HPLC‐MS/MS method was developed and validated to separate and measure the prostaglandins. The lower limits of detection (~0.5 ng/mL for PGE2 and PGD2) and quantification (1.0 ng/mL for PGE2 and PGD2) indicated that the method is highly sensitive. The calibration curves showed excellent coefficients of correlation (r > 0.99) over the range of 1.0–500.0 ng/mL, and at different levels, the accuracy ranged from 96.4 to 106.4% with an RSD < 10.0% for the precision study. This method was successfully applied using U937‐d cells. A significant dose‐dependent reduction of PGE2 and PGD2 levels occurred using 10 µg/mL (10.74 ± 2.86 and 9.60 ± 6.89%) and 50 µg/mL of extract (48.37 ± 3.24 and 53.06 ± 6.15%), suggesting that the anti‐inflammatory mechanisms evoked by M. sylvestris may be related to modulation of these mediators. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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Anthony Linden Teresa de Haro Cristina Nevado 《Acta Crystallographica. Section C, Structural Chemistry》2012,68(1):m1-m3
The molecule of the title compound, [AuCl(C27H36N2)], which belongs to a class of potentially catalytically active N‐heterocyclic carbene complexes, has crystallographic C2 symmetry and approximate C2v symmetry. The structure is isostructural with the CuI and AgI analogues. A previous report of the structure of the title compound as its toluene solvate [Fructos et al. (2005). Angew. Chem. Int. Ed. 44 , 5284–5288] has inaccurate geometry for the complex molecule as a consequence of probable incorrect refinement in the space group Cc, instead of C2/c [Marsh (2009). Acta Cryst. B 65 , 782–783]. The Au—C bond length of 1.998 (4) Å in the title compound is more consistent with the mean distance of 1.979 (14) Å found in 52 other reported [AuCl(carbene)] complexes than with the shorter distance of 1.942 (3) Å given for the refinement in the space group Cc for the toluene solvate and the value of 1.939 Å obtained from the recalculation of that structure in C2/c. 相似文献
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de Oliveira Cristina Soltovski Bet Camila Delinski Bisinella Radla Zabian Bassetto Waiga Lucas Henrique Colman Tiago André Denck Schnitzler Egon 《Journal of Thermal Analysis and Calorimetry》2018,133(3):1491-1498
Journal of Thermal Analysis and Calorimetry - Samples of potato starch (PS), sweet potato starch (SPS) and their binary mixtures, with moisture levels of 10, 15 and 20% (db), were submitted to... 相似文献
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Dr. Paula Abril Dr. M. Pilar del Río Dr. José A. López Prof. Dr. Agustí Lledós Prof. Dr. Miguel A. Ciriano Dr. Cristina Tejel 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(64):14546-14554
Alkoxylation and hydroxylation reactions of 1,5-cyclooctadiene (cod) in an iridium complex with alcohols and water promoted by the reduction of oxygen to hydrogen peroxide are described. The exo configuration of the OH/OR groups in the products agrees with nucleophilic attack at the external face of the olefin as the key step. The reactions also require the presence of a coordinating protic acid (such as picolinic acid (Hpic)) and involve the participation of a cationic diolefin iridium(III) complex, [Ir(cod)(pic)2]+, which has been isolated. Independently, this cation is also involved in easy alkoxy group exchange reactions, which are very unusual for organic ethers. DFT studies on the mechanism of olefin alkoxylation mediated by oxygen show a low-energy proton-coupled electron-transfer step connecting a superoxide–iridium(II) complex with hydroperoxide–iridium(III) intermediates, rather than peroxide complexes. Accordingly, a more complex reaction, with up to four different products, occurred upon reacting the diolefin–peroxide iridium(III) complex with Hpic. Moreover, such hydroperoxide intermediates are the origin of the regio- and stereoselectivity of the hydroxylation/alkoxylation reactions. If this protocol is applied to the diolefin–rhodium(I) complex [Rh(pic)(cod)], free alkyl ethers ORC8H11 (R=Me, Et) resulted, and the reaction is enantioselective if a chiral amino acid, such as l -proline, is used instead of Hpic. 相似文献
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Rafael Dias do Espírito Santo Rosineide Costa Simas Alviclér Magalhães Vanessa Gonçalves dos Santos Thais Regiani Ana Cristina Isler Natiza Graziele Martins Marcos Nogueira Eberlin Eduardo René Pérez González 《Journal of Physical Organic Chemistry》2013,26(4):315-321
Molecules containing the guanidinic nuclei possess several pharmacological applications, and knowing the preferred isomers of a potential drug is important to understand the way it operates pharmacologically. Benzoylguanidines were synthesized in satisfactory to good yields and characterized by NMR, Electrospray Ionization Mass Spectrometry (ESI‐MS) and Fourrier Transform InfraRed Spectroscopy techniques (FTIR). E/Z isomerism of the guanidines was studied and confirmed by NMR analysis in solution (1H‐13C Heteronuclear Single Quantum Coherence (HSQC) and Heteronuclear Multiple‐Bond Correlation (HMBC), 1H‐15N HMBC, 1H‐1H Correlation Spectroscopy (COSY) and Nuclear Overhauser Effect Spectroscopy (NOESY) experiments) at low temperatures. Compounds with p‐Cl and p‐Br aniline moiety exist mainly as Z isomer with a small proportion of E isomer, whereas compounds with p‐NO2 moiety showed a decrease in proportion of isomer Z. The results are important for the application of these molecules as enzymatic inhibitors. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献