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101.
Enrique Gil de Montes Dr. Alena Istrate Dr. Claudio D. Navo Dr. Ester Jiménez-Moreno Emily A. Hoyt Dr. Francisco Corzana Prof. Inmaculada Robina Dr. Gonzalo Jiménez-Osés Dr. Antonio J. Moreno-Vargas Dr. Gonçalo J. L. Bernardes 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(15):6255-6259
An azanorbornadiene bromovinyl sulfone reagent for cysteine-selective bioconjugation has been developed. Subsequent reaction with dipyridyl tetrazine leads to bond cleavage and formation of a pyrrole-linked conjugate. The latter involves ligation of the tetrazine to the azanorbornadiene-tagged protein through inverse electron demand Diels–Alder cycloaddition with subsequent double retro-Diels–Alder reactions to form a stable pyrrole linkage. The sequence of site-selective bioconjugation followed by bioorthogonal bond cleavage was efficiently employed for the labelling of three different proteins. This method benefits from easy preparation of these reagents, selectivity for cysteine, and stability after reaction with a commercial tetrazine, which has potential for the routine preparation of protein conjugates for chemical biology studies. 相似文献
102.
Alena Šišková Eva Macová Danilo Corradini Dušan Berek 《Journal of separation science》2013,36(18):2979-2985
Reduced sample recovery is a frequent feature of LC of macromolecules under critical conditions of enthalpic interactions (LC CC). Several methods of assessment of LC CC sample recovery are compared. A novel approach is based on an online combination of the. The LC CC column with a noninteractive SEC column. It provides not only the amount but also the molar mass of the eluted/withheld polymer. The procedure was tested with poly(methyl methacrylate), bare silica gel column packings, and “critical eluent” tetrahydrofuran/toluene. It was shown that macromolecules with higher molar masses were preferentially trapped within the LC CC column packing so that the eluted part of the sample was no longer representative. The incomplete polymer elution can make the LC CC polymer analyses susceptible to significant experimental errors. 相似文献
103.
Danilo Augusto Ferreira Fontes Magaly Andreza Marques de Lyra Jeyce Kelle Ferreira de Andrade Giovanna Christinne Rocha de Medeiros Schver Larissa Araújo Rolim Teresinha Gonçalves da Silva José Lamartine Soares-Sobrinho Severino Alves-Júnior Pedro José Rolim-Neto 《Journal of inclusion phenomena and macrocyclic chemistry》2016,85(3-4):281-288
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Finite mixture modeling of censored and missing data using the multivariate skew-normal distribution
de Alencar Francisco H. C. Galarza Christian E. Matos Larissa A. Lachos Victor H. 《Advances in Data Analysis and Classification》2022,16(3):521-557
Advances in Data Analysis and Classification - Finite mixture models have been widely used to model and analyze data from a heterogeneous populations. Moreover, data of this kind can be missing or... 相似文献
107.
Rapid and efficient method for the quantification of lychnopholide in rat plasma by liquid chromatography–tandem mass spectrometry for pharmacokinetic application
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Larissa Lachi‐Silva João Paulo Barreto Sousa Maiara Camotti Montanha Sherwin K. B. Sy João Luis Callegari Lopes Denise Brentan Silva Norberto Peporine Lopes Andréa Diniz Elza Kimura 《Biomedical chromatography : BMC》2016,30(7):1092-1096
Lychnopholide is a sesquiterpene lactone usually obtained from Lychnophora and Eremanthus species and has pharmacological activities that include anti‐inflammatory and anti‐tumor. Lychnopholide isolated from Eremanthus matogrossenssis was analyzed in this study. The aims of this study were to develop and validate an analytical methodology by LC‐MS/MS and to quantify lychnopholide in rat plasma. Chromatographic separation was achieved on a C18 column using isocratic elution with the mobile phase consisting of methanol and water (containing 0.1% formic acid) at a flow rate of 0.4 mL/min. The detection was performed in multiple‐reaction monitoring mode using electrospray ionization in positive mode. The method validation was performed in accordance with regulatory guidelines and the results met the acceptance criteria. The linear range of detection was 10–200 ng/mL (r > 0.9961). The intra‐ and inter‐day assay variability were <6.2 and <11.7%, respectively. The extraction recovery was approximately 63% using liquid–liquid extraction with chloroform. Lychnopholide was detected in plasma up to 60 min after intravenous administration in rats. This rapid and sensitive method for the analysis of the sesquiterpene lactone lychnopholide in rat plasma can be applied to pharmacokinetic studies of this compound. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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109.
Gabriel de Oliveira Isac Moraes Larissa Meirelles Rodrigues da Silva Álvaro José dos Santos-Neto Fábio Herbst Florenzano Eduardo Costa Figueiredo 《Analytical and bioanalytical chemistry》2013,405(24):7687-7696
A new restricted access molecularly imprinted polymer coated with bovine serum albumin (RAMIP-BSA) was developed, characterized, and used for direct analysis of chlorpromazine in human plasma samples. The RAMIP-BSA was synthesized using chlorpromazine, methacrylic acid, and ethylene glycol dimethacrylate as template, functional monomer, and cross-linker, respectively. Glycerol dimethacrylate and hydroxy methyl methacrylate were used to promote a hydrophilic surface (high density of hydroxyl groups). Afterward, the polymer was coated with BSA using glutaraldehyde as cross-linker, resulting in a protein chemical shield around it. The material was able to eliminate ca. 99 % of protein when a 44-mg mL?1 BSA aqueous solution was passed through it. The RAMIP-BSA was packed in a column and used for direct analysis of chlorpromazine in human plasma samples in an online column switching high-performance liquid chromatography system. The analytical calibration curve was prepared in a pool of human plasma samples with chlorpromazine concentrations ranging from 30 to 350 μg L?1. The correlation coefficient obtained was 0.995 and the limit of quantification was 30 μg L?1. Intra-day and inter-day precision and accuracy presented variation coefficients and relative errors lower than 15 % and within ?15 and 15 %, respectively. The sample throughput was 3 h?1 (sample preparation and chromatographic analysis steps) and the same RAMIP-BSA column was efficiently used for about 90 cycles. 相似文献
110.
Carina Lemke Dr. Adéla Jílková Dominic Ferber Dr. Annett Braune Anja On Dr. Patrick Johe Dr. Alena Zíková Prof. Dr. Tanja Schirmeister Dr. Michael Mareš Dr. Martin Horn Prof. Dr. Michael Gütschow 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(62):e202201636
Rhodesain is the major cysteine protease of the protozoan parasite Trypanosoma brucei and a therapeutic target for sleeping sickness, a fatal neglected tropical disease. We designed, synthesized and characterized a bimodal activity-based probe that binds to and inactivates rhodesain. This probe exhibited an irreversible mode of action and extraordinary potency for the target protease with a kinac/Ki value of 37,000 M−1s−1. Two reporter tags, a fluorescent coumarin moiety and a biotin affinity label, were incorporated into the probe and enabled highly sensitive detection of rhodesain in a complex proteome by in-gel fluorescence and on-blot chemiluminescence. Furthermore, the probe was employed for microseparation and quantification of rhodesain and for inhibitor screening using a competition assay. The developed bimodal rhodesain probe represents a new proteomic tool for studying Trypanosoma pathobiochemistry and antitrypanosomal drug discovery. 相似文献