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71.
Viscum album L., the European mistletoe, is a common species from the Viscaceae family. This evergreen hemiparasitic shrub grows on various trees and contains diverse, biologically active substances. Its chemical composition may vary depending on the time of harvest, species of the host tree and the manufacturing process. Among well-described and most active phytochemicals identified in V. album are lectins and viscotoxins, which play substantial role in cancer treatment because of their apoptotic and cytotoxic effects. Another group of compounds found in mistletoe are phenolic acids, phenylpropanoids and flavonoids with antioxidant and anti-inflammatory activities, which decrease blood pressure. Other mistletoe components include, among others, triterpenes with cytotoxic and apoptotic properties, and phytosterols, oligo- and polysaccharides. Extracts from the plant, especially aqueous, are applied in traditional and official medicine, among others in treating hypertension or arthritis. Potentially, it can also be used as a hepatoprotective or a sedative drug. 相似文献
72.
Our purpose is to investigate criteria for hyperstability of linear type functional equations. We prove that a function satisfying the equation approximately in some sense, must be a solution of it. We give some conditions on coefficients of the functional equation and a control function which guarantee hyperstability. Moreover, we show how our outcomes may be used to check whether the particular functional equation is hyperstable. Some relevant examples of applications are presented. 相似文献
73.
Jolanta Baran Andrzej Duda Adam Kowalski Ryszard Szymanski Stanislaw Penczek 《Macromolecular Symposia》1997,123(1):93-101
Chain transfer processes (ktr) taking place in the polymerization (anionic and pseudoanionic) of cyclic esters (lactones) are reviewed. These reactions are mostly responsible for the departure of these systems from the fully controlled (living) polymerizations. The ratios of kp/ktr have been determined for a number of initiating systems and the structures of the growing species are related to their selectivity, expressed by kp/ktr. It has been shown that the less reactive and more sterically crowded active species polymerize more selectively. 相似文献
74.
Straksys Antanas Kavleiskaja Tatjana Gruskiene Ruta Badokas Kazimieras Sereikaite Jolanta 《Cellulose (London, England)》2022,29(16):8705-8718
Cellulose - The study aimed to propose a new system based on xylan for β-carotene delivery into aqueous environments. The xylan fraction of low molecular weight of... 相似文献
75.
Przemysaw Zarba Anna Partyka Gniewomir Latacz Grzegorz Sataa Pawe Zajdel Jolanta Jakowska 《Molecules (Basel, Switzerland)》2022,27(21)
Serotonin 5-HT1A and 5-HT7 receptors play an important role in the pathogenesis and pharmacotherapy of depression. Previously identified N-hexyl trazodone derivatives, 2-(6-(4-(3-chlorophenyl)piperazin-1-yl)hexyl)-[1,2,4]triazolo[4,3-a]pyridin-3(2H)-one hydrochloride (7a·HCl), with high affinity for 5-HT1AR and 2-(6-(4-([1,1′-biphenyl]-2-yl)piperazin-1-yl)hexyl)-[1,2,4]triazolo[4,3-a]pyridin-3(2H)-one hydrochloride (7b·HCl), a dual-acting 5-HT1A/5-HT7 receptor ligand, were prepared with a new microwave-assisted method. The protocol for the synthesis of 7a and 7b involved reductive alkylation under a mild reducing agent. We produced the final compounds with yield of 56–63% using ethanol or 51–56% in solvent-free conditions in 4 min. We then determined the 5-HT7R binding mode for compounds 7a and 7b using in silico methods and assessed the preliminary ADME and safety properties (hepatotoxicity and CYP3A4 inhibition) using in vitro methods for 7a·HCl and 7b·HCl. Furthermore, we evaluated antidepressant-like activity of the dual antagonist of 5-HT1A/5-HT7 receptors (7b·HCl) in the forced swim test (FST) in mice. The 5-HT1AR ligand (7a·HCl) with a much lower affinity for 5-HT7R compared to that of 7b·HCl was tested comparatively. Both compounds showed antidepressant activity, while 5-HT1A/5-HT7 double antagonist 7b·HCl showed a stronger and more specific response. 相似文献
76.
Tomasz Nienałtowski Paweł Szczepanik Paweł Małecki Dr. Dorota Czajkowska-Szczykowska Dr. Stefan Czarnocki Dr. Jolanta Pawłowska Dr. Anna Kajetanowicz Prof. Karol Grela 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(67):15708-15717
A large-scale synthesis of known Ru olefin metathesis catalyst VII featuring an unsymmetrical N-heterocyclic carbene (NHC) ligand with one 2,5-diisopropylphenyl (DIPP) and one thiophenylmethylene N-substituent is reported. The optimised procedure does not require column chromatography in any step and allows for preparation of up to 0.5 kg batches of the catalyst from simple precursors. The application profile of the obtained catalyst was studied in environmentally friendly dimethyl carbonate (DMC). Although VII exhibited low efficiency in cross-metathesis (CM) with electron-deficient partners, good to excellent results were noted for substrates featuring easy to isomerise C−C double bonds. This includes polyfunctional substrates of medicinal chemistry interest, such as analogues of psychoactive 5F-PB-22 and NM-2201 and two PDE5 inhibitors—Sildenafil and Vardenafil. Finally, a larger scale ring-closing metathesis (RCM) of a Vardenafil derivative was conducted in DMC, allowing for straightforward isolation of the expected product (23 g) in high yield and with low Ru contamination level (7.7 ppm). 相似文献
77.
Mathias B. Danielsen Dr. Chenguang Lou Jolanta Lisowiec-Wachnicka Prof. Anna Pasternak Per T. Jørgensen Prof. Jesper Wengel 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(6):1368-1379
Off-target effects remain a significant challenge in the therapeutic use of gapmer antisense oligonucleotides (AONs). Over the years various modifications have been synthesized and incorporated into AONs, however, precise control of RNase H-induced cleavage and target sequence selectivity has yet to be realized. Herein, the synthesis of the uracil and cytosine derivatives of a novel class of 2′-deoxy-2′-fluoro-3′-C-hydroxymethyl-β-d -lyxo-configured nucleotides has been accomplished and the target molecules have been incorporated into AONs. Experiments on exonuclease degradation showed improved nucleolytic stability relative to the unmodified control. Upon the introduction of one or two of the novel 2′-fluoro-3′-C-hydroxymethyl nucleotides as modifications in the gap region of a gapmer AON was associated with efficient RNase H-mediated cleavage of the RNA strand of the corresponding AON:RNA duplex. Notably, a tailored single cleavage event could be engineered depending on the positioning of a single modification. The effect of single mismatched base pairs was scanned along the full gap region demonstrating that the modification enables a remarkable specificity of RNase H cleavage. A cell-based model system was used to demonstrate the potential of gapmer AONs containing the novel modification to mediate gene silencing. 相似文献
78.
The reactivity of tosylated glycerol carbonate 2 toward nucleophiles has been exploited to generate glycidol analogues protected with carbonate or carbamate groups. The activated glycerol 2 is a reasonable linking agent with thiol and alcohol nucleophiles and an excellent and selective one with primary amines, allowing efficient bis-functionalizations of glycerol. 相似文献
79.
Utko J Ejfler J Szafert S John Ł Jerzykiewicz LB Sobota P 《Inorganic chemistry》2006,45(14):5302-5306
Reactions of oligomeric "Ca(dbbfo)2" and Ca9(CH3OCH2CH2O)18(CH3OCH2CH2OH)2 with Al(CH3)3 in toluene gave tetranuclear heterobimetallic [Ca(mu-dbbfo){(mu-dbbfo)(mu-CH3)Al(CH3)2}]2 (71%) and polymeric Ca{(mu-CH3OCH2CH2O)(mu-CH3)Al(CH3)2}2 (86%). The latter can be obtained as monomeric THF adduct Ca{(mu-CH3OCH2CH2O)Al(CH3)3}2(THF)2 (78%) when a mixture of solvents is used. The results, including an initial L-lactide polymerization test, are discussed in the context of calcium alkoxo cluster degradation in solution. 相似文献
80.
The lipophilicity of a library of N-phenylamino-2-azaspiro[4.4]nonane- and [4.5]decane-1,3-dione derivatives has been determined by reversed-phase thin-layer chromatography with n-propanol-Tris buffer (pH 7.4) mixtures as mobile phases. Examination of chromatographic behaviour revealed a linear correlation between R(M) values and the concentration of n-propanol in the mobile phase. The partition coefficients (logP) were also calculated by use of the PrologP module of the Pallas computer program. Comparison of R(M0) values and calculated (logP(PALLAS)) data revealed the correlation expressed by the equation: logP(PALLAS) = 0.9995 R(M0) + 1.3451 (n = 28; r = 0.8971; F = 107.13; p < 0.05). The role of the lipophilicity in the anticonvulsant activity of a set of compounds examined is discussed: the active anticonvulsants were less lipophilic than inactive ones. 相似文献