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21.
Boschetti E 《Trends in biotechnology》2002,20(8):333-337
Hydrophobic charge induction chromatography using 4-mercapto-ethyl-pyridine as the ligand is an effective method for the separation of antibodies from a variety of feedstocks. Antibodies are adsorbed in physiological conditions without preliminary concentration. Desorption occurs when the pH is lowered, thus inducing an ionic charge of the same sign to the ligand and the antibody. Antibody capture conditions are compatible with crude samples in terms of pH, conductivity, binding capacity and expression level. The final purity of the antibody is feedstock dependent, but can reach levels of purity as high as 98%. Examples of antibody separation are given and ligand structure information discussed. 相似文献
22.
Exploring the chicken egg white proteome with combinatorial peptide ligand libraries 总被引:3,自引:0,他引:3
D'Ambrosio C Arena S Scaloni A Guerrier L Boschetti E Mendieta ME Citterio A Righetti PG 《Journal of proteome research》2008,7(8):3461-3474
The use of two types of peptide ligand libraries (PLL), containing hexapeptides terminating either with a primary amine or modified with a terminal carboxyl group, allowed the discovery and identification of a large number of previously unreported egg white proteins. Whereas the most comprehensive list up to date ( Mann, K. , Proteomics 2007, 7, 3558- 3568 ) tabulated 78 unique gene products, our findings have almost doubled that value to 148 unique protein species. From the initial nontreated egg, it was possible to find 41 protein species; the difference (107 proteins) was generated as a result of the use of PLLs from which a similar number of species (112 and 109, respectively) was evidenced. Of those, 35 proteins were the specific catch of the amino-terminus PLL, while 33 were uniquely captured by the carboxy-terminus PLL. While a number of these low-abundance proteins might have a biological role in maintaining the integrity of the egg white and protecting the yolk, others might be derived from decaying epithelial cells lining the oviduct and/or represent remnants of products from the magnum and eggshell membrane components secreted by the isthmus, which might ultimately be incorporated, even if in trace amounts, into the egg white. The list of egg white components here reported is by far the most comprehensive at present and could serve as a starting point for isolation and functional characterization of proteins possibly having novel pharmaceutical and biomedical applications. 相似文献
23.
Roux-Dalvai F Gonzalez de Peredo A Simó C Guerrier L Bouyssié D Zanella A Citterio A Burlet-Schiltz O Boschetti E Righetti PG Monsarrat B 《Molecular & cellular proteomics : MCP》2008,7(11):2254-2269
The erythrocyte cytoplasmic proteome is composed of 98% hemoglobin; the remaining 2% is largely unexplored. Here we used a combinatorial library of hexameric peptides as a capturing agent to lower the signal of hemoglobin and amplify the signal of low to very low abundance proteins in the cytoplasm of human red blood cells (RBCs). Two types of hexapeptide library beads have been adopted: amino-terminal hexapeptide beads and beads in which the peptides have been further derivatized by carboxylation. The amplification of the signal of low abundance and suppression of the signal of high abundance species were fully demonstrated by two-dimensional gel maps and nano-LC-MSMS analysis. The effect of this new methodology on quantitative information also was explored. Moreover using this approach on an LTQ-Orbitrap mass spectrometer, we could identify with high confidence as many as 1578 proteins in the cytoplasmic fraction of a highly purified preparation of RBCs, allowing a deep exploration of the classical RBC pathways as well as the identification of unexpected minor proteins. In addition, we were able to detect the presence of eight different hemoglobin chains including embryonic and newly discovered globin chains. Thus, this extensive study provides a huge data set of proteins that are present in the RBC cytoplasm that may help to better understand the biology of this simplified cell and may open the way to further studies on blood pathologies using targeted approaches. 相似文献
24.
Pereira RP Fachinetto R de Souza Prestes A Puntel RL Santos da Silva GN Heinzmann BM Boschetti TK Athayde ML Bürger ME Morel AF Morsch VM Rocha JB 《Neurochemical research》2009,34(5):973-983
Considering the important role of oxidative stress in the pathogenesis of several neurological diseases, and the growing evidence
of the presence of compounds with antioxidant properties in the plant extracts, the aim of the present study was to investigate
the antioxidant capacity of three plants used in Brazil to treat neurological disorders: Melissa officinalis, Matricaria recutita and Cymbopogon citratus. The antioxidant effect of phenolic compounds commonly found in plant extracts, namely, quercetin, gallic acid, quercitrin
and rutin was also examined for comparative purposes. Cerebral lipid peroxidation (assessed by TBARS) was induced by iron
sulfate (10 μM), sodium nitroprusside (5 μM) or 3-nitropropionic acid (2 mM). Free radical scavenger properties and the chemical
composition of plant extracts were assessed by 1′-1′ Diphenyl-2′ picrylhydrazyl (DPPH) method and by Thin Layer Chromatography
(TLC), respectively. M. officinalis aqueous extract caused the highest decrease in TBARS production induced by all tested pro-oxidants. In the DPPH assay, M. officinalis presented also the best antioxidant effect, but, in this case, the antioxidant potencies were similar for the aqueous, methanolic
and ethanolic extracts. Among the purified compounds, quercetin had the highest antioxidant activity followed by gallic acid,
quercitrin and rutin. In this work, we have demonstrated that the plant extracts could protect against oxidative damage induced
by various pro-oxidant agents that induce lipid peroxidation by different process. Thus, plant extracts could inhibit the
generation of early chemical reactive species that subsequently initiate lipid peroxidation or, alternatively, they could
block a common final pathway in the process of polyunsaturated fatty acids peroxidation. Our study indicates that M. officinalis could be considered an effective agent in the prevention of various neurological diseases associated with oxidative stress. 相似文献
25.
Elisa Fasoli Alessia Farinazzo Cheng Jun Sun Alexander V. Kravchuk Luc Guerrier Frederic Fortis Egisto Boschetti Pier Giorgio Righetti 《Journal of Proteomics》2010,73(4):733-742
When capturing proteins via combinatorial peptide ligand libraries, a method well known for drastically reducing the concentration of high-abundance proteins and substantially magnifying the signal of low-abundance species, thus leading to the discovery of a large number of proteins previously undetected in proteomes, we had constantly noticed that there would be a loss of species initially present in the untreated sample, to the tune of 5%, up to 15% in some cases. Such losses are a nuisance and hamper to some extent the unique performance of the method. In order to verify if such losses could be reduced and also to understand some mechanisms of the capture process, we introduce here an important variant to the capture operation, up to the present carried out in physiological saline at pH 7.2. In this novel protocol, the binding step is conducted at three different pH values, namely the standard one at pH 7.2, plus two additional processes, at acidic (pH 4.0) and alkaline (pH 9.3) pH values. Indeed the capture process is more extensive, with a number of additional species captured at the two pH extremes in sera and other proteomes. Interestingly, at pH 4.0 newly detected proteins were mostly acidic, while at the alkaline pH additional protein species were more evenly distributed throughout the pI range towards the alkaline area. The role of pH in the complex mechanism of binding among the hexapeptide library and the various proteomes being analyzed is discussed and evaluated. Due to significant changes in protein patterns with pH, recommendations are thus made to increase the possibility to find additional gene products illustrated by two examples (snake venom and leaf protein extract). Keeping under control the environmental pH when facing reproducibility studies or for comparative proteomics profiling is also a general rule suggested by this study. 相似文献
26.
Monogononts reproduce by parthenogenesis punctuated by events of mixis that generate ‘resting eggs’, which actually are embryos
whose development is arrested. We document the nuclei number and position of the resting eggs of nine rotifer species (Brachionus plicatilis, B. calyciflorus, B. manjavacas, Plationus patulus, Epiphanes senta, E. chihuahuaensis, Rhinoglena frontalis, Lecane bulla and Sinantherina socialis) in the attempt to assess the stage at which dormant embryos are arrested. The morphology of the entire embryos was reconstructed
visualising nuclear DNA using confocal microscopy, and their developmental stage identified. Two groups of species were identified:
dormant embryos of one group possessed on average less than 30 nuclei, with low variation within and between species, and
the stage may correspond to early gastrula; embryos in the second group contain relatively more nuclei, averaging around 40–60,
with higher variation within species. The two groups of species seem not to reflect any phylogenetic relationship. Consequences
of the dormant embryo stages are discussed. 相似文献
27.
Ernetti Julia R. Boschetti Joana P. Delazeri Francieli De Bastiani Veluma I. M. Pontes Mariana R. Ribeiro Luisa P. Lingnau Rodrigo Toledo Luís Felipe Lucas Elaine M. 《Hydrobiologia》2020,847(16):3355-3364
Hydrobiologia - Pithecopus rusticus is an endemic amphibian restricted to the type locality, in southern Brazil, and possibly endangered to extinction, due to habitat degradation. However, an... 相似文献
28.
M P Cordier G Sournies Y Domenichini C Coicaud M Guillaud J M Thoulon F Charvet R Boschetti J M Robert 《Journal de génétique humaine》1985,33(3-4):295-300
100 Necropsies have been performed from January 1983 to June 1984, on 53 abortus and stillborn and 47 therapeutic terminations of pregnancy. All fetuses came from the same obstetric unit. Half spontaneous fetal deaths remained of unknown aetiology; in 18 cases (34%) placental, maternal or pregnancy pathology existed; fetal abnormalities were discovered in 10 (18%). As for therapeutic interruptions of pregnancy (the indications of which are detailed) the importance of ultrasonography emphasized since this technique allowed 25 of the 47 prenatal diagnosis. The importance of necropsy to help precise diagnosis and subsequent counselling is also recalled. 相似文献
29.
Breidenbach Eric; Jenni Erika; Leu Stefan; Boschetti Arminio 《Plant & cell physiology》1988,29(1):1-7
The relative contents of the mRNAs were analyzed for the 32kDa herbicide-binding protein and for the large subunit of ribulose-l,5-bisphosphatecarboxylase in the membrane fraction and in the soluble fractionof chloroplasts from Chlamydomonas reinhardii. The presenceof mRNA for the two proteins in both subchloroplast fractionswas demonstrated by in vitro translation of isolated RNA inthe reticulocyte lysate. The relative amounts of the two mRNAswere measured by hybridizations with cloned chloroplast DNAprobes at two stages of the cell cycle. Both mRNAs were distributedin the same ratio between membrane and soluble fractions, about75% of both mRNAs being in the membrane and 25% in the solublefraction. Therefore, in chloroplasts the accumulation of mRNAson thylakoid membranes does not reflect the final localizationof soluble and membrane proteins.
1Present address: Department of Biology, Ben Gurion University,Beer-Sheva, Israel. (Received April 28, 1987; Accepted September 29, 1987) 相似文献
30.
Large scale production of human albumin: three years experience of an affinity chromatography process. 总被引:1,自引:0,他引:1
Immobilized Cibacron Blue is a well-known tool for the separation of a number of proteins and enzymes. Among them, human plasma albumin was easily purified from crude plasma and consequently, this approach represents an interesting way for a production scale. Our data describes about three years of experience in the production of human albumin using large columns of immobilized Cibacron Blue. The amount of albumin produced per cycle was about 250 g on a column of about 50 l. Over 500 cycles the final purity of albumin was very high and constant (98-100%). The albumin yield of the chromatographic fractionation was approximately 82%. The column performance remained acceptable when regeneration operations were applied to the sorbent. The long life of the sorbent renders this approach very attractive and economically acceptable for large scale applications. 相似文献