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101.
LC/MS/MS analysis of α‐tocopherol and coenzyme Q10 content in lyophilized royal jelly,beebread and drone homogenate 下载免费PDF全文
Marta Hryniewicka Agnieszka Karpinska Marta Kijewska Monika Joanna Turkowicz Joanna Karpinska 《Journal of mass spectrometry : JMS》2016,51(11):1023-1029
This study shows the results of application liquid chromatography‐tandem mass spectrometry (LC/MS/MS) for assay of the content of α‐tocopherol and coenzyme Q10 in bee products of animal origin, i.e. royal jelly, beebread and drone homogenate. The biological matrix was removed using extraction with n‐hexane. It was found that drone homogenate is a rich source of coenzyme Q10. It contains only 8 ± 1 µg/g of α‐tocopherol and 20 ± 2 µg/g of coenzyme Q10. The contents of assayed compounds in royal jelly were 16 ± 3 and 8 ± 0.2 µg/g of α‐tocopherol and coenzyme Q10, respectively. Beebread appeared to be the richest of α‐tocopherol. Its level was 80 ± 30 µg/g, while the level of coenzyme Q10 was only 11.5 ± 0.3 µg/g. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
102.
Parasitic diseases are still a huge problem for mankind. They are becoming the main cause of chronic diseases in the world. Migration of the population, pollution of the natural environment, and climate changes cause the rapid spread of diseases. Additionally, a growing resistance of parasites to drugs is observed. Many research groups are looking for effective antiparasitic drugs with low side effects. In this work, we present the current trends in the search for antiparasitic drugs. We report known drugs used in other disease entities with proven antiparasitic activity and research on new chemical structures that may be potential drugs in parasitic diseases. The described investigations of antiparasitic compounds can be helpful for further drug development. 相似文献
103.
Monika Wanat Maura Malinska Andrzej Kutner Krzysztof Wo
niak 《Molecules (Basel, Switzerland)》2022,27(6)
Vitamins D are a group of fat-soluble secosteroids which play a regulatory role in the functioning of most cells. Rational design of new vitamin D analogs, of increased therapeutic potency and lowered calcemic side effects, requires high-resolution initial structures and a deep understanding of interactions with the molecular targets. In this paper, using quantum crystallography, we present the first determination of the experimental quantitative charge density of an advanced intermediate of vitamin D analogues as well as a reconstruction of the theoretical electron density of final vitamin D analogues. Application of these methods allows for topological and electrostatic interaction energy analysis. We showed that the A-ring chair conformation has a significant influence on the topological properties of vitamin D compounds. Moreover, the interactions between the CD-ring and side-chain additionally stabilize the crystal structure. These results are supported by our theoretical calculations and previous biological studies. 相似文献
104.
Sara Janowska Dmytro Khylyuk Anna Bielawska Anna Szymanowska Agnieszka Gornowicz Krzysztof Bielawski Jarosaw Noworl Sawomir Mandziuk Monika Wujec 《Molecules (Basel, Switzerland)》2022,27(6)
We designed and synthesized the 1,3,4-thiadiazole derivatives differing in the structure of the substituents in C2 and C5 positions. The cytotoxic activity of the obtained compounds was then determined in biological studies using MCF-7 and MDA-MB-231 breast cancer cells and normal cell line (fibroblasts). The results showed that in both breast cancer cell lines, the strongest anti-proliferative activity was exerted by 2-(2-trifluorometylophenylamino)-5-(3-methoxyphenyl)-1,3,4-thiadiazole. The IC50 values of this compound against MCF-7 and MDA-MB-231 breast cancer cells were 49.6 µM and 53.4 µM, respectively. Importantly, all new compounds had weaker cytotoxic activity on normal cell line than on breast cancer cell lines. In silico studies demonstrated a possible multitarget mode of action for the synthesized compounds. The most likely mechanism of action for the new compounds is connected with the activities of Caspase 3 and Caspase 8 and activation of BAX proteins. 相似文献
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107.
K. Pradeesh Monika Agarwal K. Koteswara Rao G. Vijaya Prakash 《Solid State Sciences》2010,12(1):95-98
Quasi-one-dimensional lead (II) iodide compound, C14H18N2Pb2I6, with unique crystal structure was synthesized and solved for the crystal structure. These novel inorganic-organic hybrids have high thermal stability of upto 300 °C and show excitonic and charge-transfer features in their optical properties. An attempt has been made to understand the structural and optical mechanisms between inorganic one-dimensional polymeric PbI nano ribbons and the guest organic moiety for future applications in nanoscaled electronic devices. 相似文献
108.
Monika Szulc Justyna Samaszko-Fiertek Rafał Ślusarz Kornelia Kowalska Artur Sikorski 《Journal of carbohydrate chemistry》2016,35(3):161-171
Solid phase peptide synthesis (SPPS) of two selected muramyl pentapeptide derivatives is described. The simplicity of removing the protecting groups via one-step deprotection and cleavage from the resin is the biggest advantage of SPPS. Using this method, two muramyl pentapeptide derivatives, D-MurN3-L-Ala-D-iGlu-L-Lys-D-Ala-D-Ser (5) and D-MurN3-L-Ala-D-iGlu-L-Lys-D-Ala-D-Ala (6), were obtained. Their chemical structures were confirmed by high-resolution mass spectrometry (HRMS) and nuclear magnetic resonance (NMR) spectroscopy. To determine the absolute configuration of the carbon atom in the side chain of the muramic acid derivative, single-crystal X-ray diffraction measurements were recorded. 相似文献
109.
High alpha/beta-anomer selectivity in molecular recognition of carbohydrates by artificial receptors
[structure: see text] New effective, acyclic, pyridine-based receptors 1-3 show remarkable alpha/beta binding selectivity in the recognition of monosaccharides. They are able to participate in cooperative and bidentate hydrogen bonds with sugar hydroxyls as well as in CH-pi interactions with CH's of sugar molecules. 相似文献
110.
We propose a conceptual framework that leads to an abstract characterization for the exact solvability of Calabi–Yau varieties in terms of abelian varieties with complex multiplication. The abelian manifolds are derived from the cohomology of the Calabi–Yau manifold, and the conformal field theoretic quantities of the underlying string emerge from the number theoretic structure induced on the varieties by the complex multiplication symmetry. The geometric structure that provides a conceptual interpretation of the relation between geometry and conformal field theory is discrete, and turns out to be given by the torsion points on the abelian varieties. 相似文献