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41.
In this paper, partitioning behaviors of typical neutral (Alanine), acidic (Glutamic acid) and basic (Lysine) amino acids into imidazolium-based ionic liquids [C4mim][PF6], [C6mim][PF6], [C8mim][PF6], [C6mim][BF4] and [C8mim][BF4] as extracting solvents were examined. [C6mim][BF4] showed the best efficiency for partitioning of amino acids. The partition coefficients of amino acids in ionic liquids were found to depend strongly on pH of the aqueous solution, amino acid and ionic liquid chemical structures. Different chemical forms of amino acids in aqueous solutions were pH dependent, so the pH value of the aqueous phase was a determining factor for extraction of amino acids into ionic liquid phase. Both water content of ionic liquids and charge densities of their anionic and cationic parts were important factors for partitioning of cationic and anionic forms of amino acids into ionic liquid phase. Extracted amino acids were back extracted into phosphate buffer solutions adjusted on appropriate pH values. The results showed that ionic liquids could be used as suitable modifiers on the stationary phase of an HPLC column for efficient separation of acidic, basic, and neutral amino acids.  相似文献   
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Treatment of Linum album cell cultures with 10 μM salicylic acid (SA) for 3 days improved podophyllotoxin (PTOX) production up to 333 μg/g dry weight (DW): over three times that of the control cultures. qPCR analyses showed that in SA-treated cells, the expression of the genes coding for phenylalanine ammonia-lyase (PAL), cinnamoyl-CoA reductase (CCR) and cinnamyl-alcohol dehydrogenase (CAD), all involved in the first steps of PTOX biosynthesis, also increased reaching a peak 8–12 h after the treatment. Expression of the pinoresinol-lariciresinol reductase gene (PLR), which is involved in one of the last biosynthetic steps, was not affected by SA. The selective action of SA on these genes can be applied to control the biotechnological production of this anticancer agent.  相似文献   
44.
Autosomal recessive gene defects are arguably the most important, but least studied genetic causes of severe cognitive dysfunction. Homozygosity mapping in 78 consanguineous Iranian families with nonsyndromic autosomal recessive mental retardation (NS-ARMR) has enabled us to determine the chromosomal localization of at least 8 novel gene loci for this condition. Our data suggest that in the Iranian population NS-ARMR is very heterogeneous, and they argue against the existence of frequent gene defects that account for more than a few percent of the cases. Mohammad Mahdi Motazacker and Masoud Garshasbi have contributed equally to this work.  相似文献   
45.
The diagnostic features of otolith morphology were provided for the clupeid fishes of the Iranian brackish and marine resources to be used as diagnostic features for the identification of clupeids diversity in these regions. Fish individuals belong to 20 species belong to 13 genera, and four families were collected from the Caspian Sea, the Persian Gulf and the Makran zone of the Oman Sea. Overall, seven otolith morphotypes were distinguished, that is lanceolated (45%), fusiform (20%), boot-like (15%) and clamp-like, pentagonal, elliptic and rectangular (each 5%, respectively). The univariate analysis showed that all variables except shape index [sulcus area (SS)/otolith area (OS)] and ROx (roundness) were significantly different among the clupeid species. The interspecific relationships of the otoliths were analysed based on the data of otolith morphology and otolith shape indices. Both dendrograms showed somehow an obvious separation among the studied species. However, the interspecific relationships in the dendrogram based on the otolith morphology have a better resolution. These phenotypic relationships based on otolith morphology among the studied clupeids are largely consistent with the previous hypothesis on the systematics of these fishes and emphasized that the morphological and morphometric features of the otolith, which are highlighted in this study, could be adequately used as diagnostic features for the identification of clupeids diversity.  相似文献   
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Molecular Biology Reports - This study was aimed to evaluate the antibiotic resistance, biofilm formation, and genetic diversity of carbapenem-resistant Pseudomonas aeruginosa (CRPA) strains...  相似文献   
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Molecular Biology Reports - Aberrant expression of long non-coding RNAs (lncRNAs) can contribute to the pathogenesis of coronary artery disease (CAD). In this study, we aimed to evaluate the...  相似文献   
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Length–weight parameters are presented for four endemic tooth‐carps of the genus Aphanius from Iran.  相似文献   
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Stable isotope standards and capture by antipeptide antibodies (SISCAPA) couples affinity enrichment of peptides with stable isotope dilution and detection by multiple reaction monitoring mass spectrometry to provide quantitative measurement of peptides as surrogates for their respective proteins. In this report, we describe a feasibility study to determine the success rate for production of suitable antibodies for SISCAPA assays in order to inform strategies for large-scale assay development. A workflow was designed that included a multiplex immunization strategy in which up to five proteotypic peptides from a single protein target were used to immunize individual rabbits. A total of 403 proteotypic tryptic peptides representing 89 protein targets were used as immunogens. Antipeptide antibody titers were measured by ELISA and 220 antipeptide antibodies representing 89 proteins were chosen for affinity purification. These antibodies were characterized with respect to their performance in SISCAPA-multiple reaction monitoring assays using trypsin-digested human plasma matrix. More than half of the assays generated were capable of detecting the target peptide at concentrations of less than 0.5 fmol/μl in human plasma, corresponding to protein concentrations of less than 100 ng/ml. The strategy of multiplexing five peptide immunogens was successful in generating a working assay for 100% of the targeted proteins in this evaluation study. These results indicate it is feasible for a single laboratory to develop hundreds of assays per year and allow planning for cost-effective generation of SISCAPA assays.  相似文献   
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