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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
54.
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
55.
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
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Łapczuk-Krygier Agnieszka Jaśkowska Jolanta Jasiński Radomir 《Chemistry of Heterocyclic Compounds》2018,54(12):1172-1174
Chemistry of Heterocyclic Compounds - The molecular mechanism of nitrous acid elimination from 5-nitro-3-phenyl-4,5-dihydroisoxazole systems has been explored using DFT computational study. It was... 相似文献
58.
Analysis of Cibacron blue F3G-A interaction with therapeutic proteins by MALDI-TOF mass spectrometry 总被引:1,自引:0,他引:1
The formation of the complexes between Cibacron blue F3G-A and two therapeutic proteins, recombinant human interferon-alpha2b and recombinant human growth hormone, was investigated. The method of time-resolved limited proteolysis coupled with MALDI-TOF mass spectrometry was used. The analysis of peptide maps revealed that A(17)HR(19) and L(20)HQLAFDTYQEFEEAYIPK(38) of hGH, and R(14)TLMLLAQMR(23) and D(33)RHDFGFPQEEFGNQFQK(50) of hIFN-alpha2b, exhibit affinity to Cibacron blue F3G-A. Copyright (c) 2008 John Wiley & Sons, Ltd. 相似文献
59.
Cellulose-based carriers Granocel were specially prepared and optimised for covalent immobilization of enzymes. The effects
of carrier characteristics such as pore size, chemistry of anchor groups and their density on invertase immobilization efficiency
were evaluated. It was found that the preferential adsorption/binding of the enzyme to a carrier during coupling and its activity
after immobilization depended on microenvironmental effects created by hydrophilic surface of the carrier, functional groups
and their activators. The best preparations (activity approx. 300 U/mL, high storage stability) were obtained for NH2-Granocel activated with glutaraldehyde. It is probably due to Granocel modification with pentaethylenehexamine that gave
a 19-atom spacer arm. The enzyme concentration in coupling mixture was optimised as well. The kinetic parameters of sucrose
hydrolysis for native and immobilized invertase were evaluated. Compared to the native invertase, K
m
value of immobilized enzyme was only twice higher with about three times lower substrate inhibition. Reaction runs in a well
mixed batch reactors with native and immobilized invertase showed slightly slower reaction rate in the case of the enzyme
covalently bound to Granocel. Very good stability of cellulose-based carrier was proved experimentally by 20 successive reaction
runs in a batch reactor. 相似文献
60.
Jolanta Kosman 《Quaestiones Mathematicae》2016,39(5):637-642
In this paper we characterize the pairs (A?, A+) of disjoint subsets of perfectly normal topological space which can be separated by a lower and an upper semicontinuous function with a closed graph. 相似文献