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951.
A multivariate calibration procedure for UV/VIS spectrometric monitoring of BHK‐21 cell metabolism and growth
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Letícia de Almeida Parizotto Wagner Antonio Chagas Erica Salla dos Santos Aline Tojeira Prestia Caricati Alexandre Gonçalves de Rezende Bruno Labate Vale da Costa Daniela Cristina Ventini Monteiro Vera Lucia Lopes Boldorini Soraia Attie Calil Jorge Renato Mancini Astray Carlos Augusto Pereira Celso Pereira Caricati Aldo Tonso 《Biotechnology progress》2014,30(1):241-248
Monitoring mammalian cell culture with UV–vis spectroscopy has not been widely explored. The aim of this work was to calibrate Partial Least Squares (PLS) models from off‐line UV–vis spectral data in order to predict some nutrients and metabolites, as well as viable cell concentrations for mammalian cell bioprocess using phenol red in culture medium. The BHK‐21 cell line was used as a mammalian cell model. Spectra of samples taken from batches performed at different dissolved oxygen concentrations (10, 30, 50, and 70% air saturation), in two bioreactor configurations and with two strategies to control pH were used to calibrate and validate PLS models. Glutamine, glutamate, glucose, and lactate concentrations were suitably predicted by means of this strategy. Especially for glutamine and glucose concentrations, the prediction error averages were lower than 0.50 ± 0.10 mM and 2.21 ± 0.16 mM, respectively. These values are comparable with those previously reported using near infrared and Raman spectroscopy in conjunction with PLS. However, viable cell concentration models need to be improved. The present work allows for UV–vis at‐line sensor development, decrease cost related to nutrients and metabolite quantifications and establishment of fed‐batch feeding schemes. © 2013 American Institute of Chemical Engineers Biotechnol. Prog., 30:241–248, 2014 相似文献
952.
953.
Cassiano Felippe Gon?alves-de-Albuquerque Patrícia Burth Adriana Ribeiro Silva Isabel Matos Medeiros de Moraes Flora Magno de Jesus Oliveira Ricardo Erthal Santelli Aline Soares Freire Gerson Silva de Lima Emilson Domingos da Silva Camila Ignácio da Silva Ver?nica Morandi Patrícia Torres Bozza Mauricio Younes-Ibrahim Hugo Caire de Castro Faria Neto Mauro Velho de Castro Faria 《Respiratory research》2014,15(1)
Background
Leptospiral glycolipoprotein (GLP) is a potent and specific Na/K-ATPase inhibitor. Severe pulmonary form of leptospirosis is characterized by edema, inflammation and intra-alveolar hemorrhage having a dismal prognosis. Resolution of edema and inflammation determines the outcome of lung injury. Na/K-ATPase activity is responsible for edema clearance. This enzyme works as a cell receptor that triggers activation of mitogen-activated protein kinase (MAPK) intracellular signaling pathway. Therefore, injection of GLP into lungs induces injury by triggering inflammation.Methods
We injected GLP and ouabain, into mice lungs and compared their effects. Bronchoalveolar lavage fluid (BALF) was collected for cell and lipid body counting and measurement of protein and lipid mediators (PGE2 and LTB4). The levels of the IL-6, TNFα, IL-1B and MIP-1α were also quantified. Lung images illustrate the injury and whole-body plethysmography was performed to assay lung function. We used Toll-like receptor 4 (TLR4) knockout mice to evaluate leptospiral GLP-induced lung injury. Na/K-ATPase activity was determined in lung cells by nonradioactive rubidium incorporation. We analyzed MAPK p38 activation in lung and in epithelial and endothelial cells.Results
Leptospiral GLP and ouabain induced lung edema, cell migration and activation, production of lipid mediators and cytokines and hemorrhage. They induced lung function alterations and inhibited rubidium incorporation. Using TLR4 knockout mice, we showed that the GLP action was not dependent on TLR4 activation. GLP activated of p38 and enhanced cytokine production in cell cultures which was reversed by a selective p38 inhibitor.Conclusions
GLP and ouabain induced lung injury, as evidenced by increased lung inflammation and hemorrhage. To our knowledge, this is the first report showing GLP induces lung injury. GLP and ouabain are Na/K-ATPase targets, triggering intracellular signaling pathways. We showed p38 activation by GLP-induced lung injury, which was may be linked to Na/K-ATPase inhibition. Lung inflammation induced by GLP was not dependent on TLR4 activation. 相似文献954.
955.
Washington Luiz Assuno Pereira David Marcial Fernandez Conga Klena Sarges Marruaz da Silva Reinaldo Jos da Silva Aline Amaral Imbeloni 《Journal of medical primatology》2021,50(1):82-85
This study described the hepatobiliary anatomopathological lesions associated with trematode Platynosomum illiciens parasitism in Neotropical primates kept in captivity. In the evaluated organs, we observed portal fibrosis, biliary epithelial hyperplasia, and inflammatory reaction with a predominance of lymphocytes and plasmocytes, and in some cases infiltration of eosinophils and neutrophils. 相似文献
956.
Haplotypes in the Interleukin 8 Gene and Their Association with Chronic Periodontitis Susceptibility
Scarel-Caminaga RM Kim YJ Viana AC Curtis KM Corbi SC Sogumo PM Orrico SR Cirelli JA 《Biochemical genetics》2011,49(5-6):292-302
Interleukin-8 (IL-8), which is responsible for the migration and activation of neutrophils, is an important inflammatory mediator involved in the initiation and amplification of acute inflammatory reactions and chronic inflammatory processes. IL-8 plays an important role in periodontitis, an inflammatory disease characterized by the loss of connective tissue and alveolar bone. The aim of this study was to investigate whether the SNPs rs2227307 (+396) and rs2227306 (+781), and the haplotypes they formed together with the previously investigated rs4073 (-251), were associated with chronic periodontitis susceptibility. Clinical periodontal exams were performed and DNA samples were collected from 493 individuals (223 with periodontitis and 270 controls). Associations between SNPs, haplotypes, and subject phenotypes were analyzed using the χ(2) test followed by multivariate logistic regression modeling. We conclude that the +396TT genotype and the haplotypes ATC/TTC and AGT/TGC were significantly associated with chronic periodontitis susceptibility in Brazilians. 相似文献
957.
Gelson Manzoni de Oliveira Manfredo Hörner Aline Machado Jorge H.S.K. Monteiro 《Inorganica chimica acta》2011,366(1):203-859
Deprotonated 3-(4-nitrophenyl)-1-phenyltriazene N-oxide reacts with YCl3·6H2O and LnCl3·6H2O (Ln = Eu, Ho, Yb) to give the monoclinic chelate complexes [Y{O2N(C6H4)NNN(O)Ph}4](Et3NH)·H2O (1) (Ph = C6H5; Et = C2H5) and [LnIII{O2N(C6H4)NNN(O)Ph}4](Et3NH)·H2O·{CH3OH∗} {LnIII = Eu (2), Ho (3), Yb∗ (4), in which the metal centers present a square antiprismatic configuration. As already observed for hydrated ammonium complexes of triazene-oxides ligands with (C6H4)−NO2 groups, multiple, effective O···H and N···H interactions hold the species in supramolecular 3D assemblies. The optical and the luminescent properties of the triazene-oxide europium complex 2 are also presented and fully discussed. 相似文献
958.
959.
Marbaix AY Noël G Detroux AM Vertommen D Van Schaftingen E Linster CL 《The Journal of biological chemistry》2011,286(48):41246-41252
The reduced forms of NAD and NADP, two major nucleotides playing a central role in metabolism, are continuously damaged by enzymatic or heat-dependent hydration. We report the molecular identification of the eukaryotic dehydratase that repairs these nucleotides and show that this enzyme (Carkd in mammals, YKL151C in yeast) catalyzes the dehydration of the S form of NADHX and NADPHX, at the expense of ATP, which is converted to ADP. Surprisingly, the Escherichia coli homolog, YjeF, a bidomain protein, catalyzes a similar reaction, but using ADP instead of ATP. The latter reaction is ascribable to the C-terminal domain of YjeF. This represents an unprecedented example of orthologous enzymes using either ADP or ATP as phosphoryl donor. We also show that eukaryotic proteins homologous to the N-terminal domain of YjeF (apolipoprotein A-1-binding protein (AIBP) in mammals, YNL200C in yeast) catalyze the epimerization of the S and R forms of NAD(P)HX, thereby allowing, in conjunction with the energy-dependent dehydratase, the repair of both epimers of NAD(P)HX. Both enzymes are very widespread in eukaryotes, prokaryotes, and archaea, which together with the ADP dependence of the dehydratase in some species indicates the ancient origin of this repair system. 相似文献
960.
Pellissier LP Barthet G Gaven F Cassier E Trinquet E Pin JP Marin P Dumuis A Bockaert J Banères JL Claeysen S 《The Journal of biological chemistry》2011,286(12):9985-9997
The discovery that class C G protein-coupled receptors (GPCRs) function as obligatory dimeric entities has generated major interest in GPCR oligomerization. Oligomerization now appears to be a common feature among all GPCR classes. However, the functional significance of this process remains unclear because, in vitro, some monomeric GPCRs, such as rhodopsin and β(2)-adrenergic receptors, activate G proteins. By using wild type and mutant serotonin type 4 receptors (5-HT(4)Rs) (including a 5-HT(4)-RASSL) expressed in COS-7 cells as models of class A GPCRs, we show that activation of one protomer in a dimer was sufficient to stimulate G proteins. However, coupling efficiency was 2 times higher when both protomers were activated. Expression of combinations of 5-HT(4), in which both protomers were able to bind to agonists but only one could couple to G proteins, suggested that upon agonist occupancy, protomers did not independently couple to G proteins but rather that only one G protein was activated. Coupling of a single heterotrimeric G(s) protein to a receptor dimer was further confirmed in vitro, using the purified recombinant WT RASSL 5-HT(4)R obligatory heterodimer. These results, together with previous findings, demonstrate that, differently from class C GPCR dimers, class A GPCR dimers have pleiotropic activation mechanisms. 相似文献