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391.
Amanda Ribeiro Ferreira Balwan Singh Monica Cabrera-Mora Alana Cristina Magri De Souza Maria Teresa Queiroz Marques Luis Cristov?o Sobrino Porto Fatima Santos Dalma Maria Banic J. Mauricio Calvo-Calle Joseli Oliveira-Ferreira Alberto Moreno Josué Da Costa Lima-Junior 《PloS one》2014,9(8)
The development of modular constructs that include antigenic regions targeted by protective immune responses is an attractive approach for subunit vaccine development. However, a main concern of using these vaccine platforms is how to preserve the antigenic identity of conformational B cell epitopes. In the present study we evaluated naturally acquired antibody responses to a chimeric protein engineered to contain a previously defined immunodominant domain of the Plasmodium vivax reticulocyte binding protein-1 located between amino acid positions K435-I777. The construct also includes three regions of the cognate protein (F571-D587, I1745-S1786 and L2235-E2263) predicted to contain MHC class II promiscuous T cell epitopes. Plasma samples from 253 naturally exposed individuals were tested against this chimeric protein named PvRMC-RBP1 and a control protein that includes the native sequence PvRBP123-751 in comparative experiments to study the frequency of total IgG and IgG subclass reactivity. HLA-DRB1 and HLA-DQB1 allelic groups were typed by PCR-SSO to evaluate the association between major HLA class II alleles and antibody responses. We found IgG antibodies that recognized the chimeric PvRMC-RBP1 and the PvRBP123-751 in 47.1% and 60% of the studied population, respectively. Moreover, the reactivity index against both proteins were comparable and associated with time of exposure (p<0.0001) and number of previous malaria episodes (p<0.005). IgG subclass profile showed a predominance of cytophilic IgG1 over other subclasses against both proteins tested. Collectively these studies suggest that the chimeric PvRMC-RBP1 protein retained antigenic determinants in the PvRBP1435–777 native sequence. Although 52.9% of the population did not present detectable titers of antibodies to PvRMC-RBP1, genetic restriction to this chimeric protein does not seem to occur, since no association was observed between the HLA-DRB1* or HLA-DQB1* alleles and the antibody responses. This experimental evidence strongly suggests that the identity of the conformational B cell epitopes is preserved in the chimeric protein. 相似文献
392.
Ednildes de Almeida Olympio Rua Marcella Leite Porto Jean Pierre Louzada Ramos Breno Valentim Nogueira Silvana dos Santos Meyrelles Elisardo Corral Vasquez Thiago de Melo Costa Pereira 《Journal of biomedical science》2014,21(1)
Background
Although cigarette smoke is known to be a complex mixture of over 4000 substances that can lead to damage through active or passive smoking, its mechanisms and biochemical consequences in pregnancy and neonates are not yet fully understood. Therefore, in the present study, we propose to study the impact of smoking during gestation on the viability of blood mononuclear cells (MNC) from umbilical cords of newborns to assess the degree of oxidative stress and cell viability. After childbirth, the cord blood and the umbilical cord were immediately collected in public hospitals in Greater Vitoria, ES, Brazil. Flow cytometry was used to analyze the cord blood followed by biochemical and histological tests to analyze possible changes in the umbilical cord.Results
Pregnant smokers had a reduction of MNC viability from the umbilical cord (10%), an increase in the production of reactive oxygen species (ROS) and an increase in cell apoptosis (~2-fold) compared to pregnant non-smokers. In the umbilical cord, it was observed an increase of advanced oxidation protein products - AOPP (~2.5-fold) and a loss of the typical architecture and disposition of endothelial cells from the umbilical artery.Conclusions
These data suggest that maternal cigarette smoking during pregnancy (even in small amounts) may compromise the viability of MNC cells and damage the umbilical cord structure, possibly by excessive ROS bioavailability. 相似文献393.
Cesar Augusto Sam Tiago Vilanova-Costa Hellen Karine Paes Porto Flávia de Castro Pereira Aliny Pereira de Lima Wagner Batista dos Santos Elisângela de Paula Silveira-Lacerda 《Biometals》2014,27(3):459-469
Lung cancer is one of the leading causes of death in the world, and non-small cell lung carcinoma accounts for approximately 75–85 % of all lung cancers. In the present work, we studied the antitumor activity of the compound cis-(dichloro)tetramineruthenium(III) chloride {cis-[RuCl2(NH3)4]Cl} against human lung carcinoma tumor cell line A549. The present study aimed to investigate the relationship between the expression of MDR1 and CYP450 genes in human lung carcinoma cell lines A549 treated with cisCarboPt, cisCRu(III) and cisDRu(III). The ruthenium-based coordinated complexes presented low cytotoxic and antiproliferative activities, with high IC50 values, 196 (±15.49), 472 (±20.29) and 175 (±1.41) for cisCarboPt, cisCRu(III) and cisDRu(III), respectively. The tested compounds induced apoptosis in A549 tumor cells as evidenced by caspase 3 activation, but only at high concentrations. Results also revealed that the amplification of P-gp gene is greater in A549 cells exposed to cisCarboPt and cisCRu(III) than cisDRu(III). Taken together all these results strongly demonstrate that MDR-1 over-expression in A549 cells could be associated to a MDR phenotype of these cells and moreover, it is also contributing to the platinum, and structurally-related compound, resistance in these cells. The identification and characterization of novel mechanisms of drug resistance will enable the development of a new generation of anti-cancer drugs that increase cancer sensitivity and/or represent more effective chemotherapeutic agents. 相似文献
394.
395.
Santi M. Mandal Rupa Pegu William F. Porto Octavio L. Franco Sanjay Pratihar 《Bioorganic & medicinal chemistry letters》2017,27(10):2135-2138
Towards the search for a new generation of antibiotics to control methicillin-resistant Staphylococcus aureus (MRSA), the design and synthesis of various bis indolyl methane (BIM) derivatives based on their different electron donor and acceptor properties of the substituents have been made, in which boronic acid derivatives of BIM are found to be active against MRSA. The observed evidence with the lead compound reveals their strong anti-MRSA activity, which paves the way of design and further development of a new generation antibiotics. 相似文献
396.
Computational Investigation of Growth Hormone Receptor Trp169Arg Heterozygous Mutation in a Child With Short Stature 下载免费PDF全文
397.
Salmon DN Piva LC Binati RL Rodrigues C Vandenberghe LP Soccol CR Spier MR 《Bioprocess and biosystems engineering》2012,35(7):1067-1079
Schizophyllum commune produces phytase through solid-state fermentation using different agroindustrial residues. After optimization of phytase production, a maximal level of phytase (113.7 Units/gram of dry substrate) was obtained in wheat bran based medium containing 5% sucrose, 50% humidity, 7.5% of biomass at 33 °C pH 7.0 during 72 h and a 285% improvement in enzyme titre was achieved. Analysis of fermentation parameters profile for phytase production showed the highest productivity (1.466 Units/gram of dry substrate/hour) in 66 h of fermentation. Phytase has an optimal pH of 5.0, an optimal temperature of 50 °C and K (m) and V (max) values of 0.16 mM and 1.85 μmol mL(-1) min(-1), respectively. Phytase activity was stimulated essentially in the presence of K(+), Ca(2+), Mg(2+), Mn(2+), Zn(2+), Cu(2+), Fe(2+), Fe(3+), Co(2+), Ni(2+), acetate and citrate at concentrations of 1 mM. Phytase had the best shelf life when stored at a cooling temperature, maintaining 38% of its initial activity after 112 days of storage, and still presenting enzymatic activity after 125 days of storage. Stability studies of phytase performed in aqueous enzyme extracts showed satisfactory results using polyethyleneglycol 3350, carboxymethylcellulose, methylparaben, mannitol and benzoic acid in concentrations of 0.25, 0.025, 0.025, 0.25, and 0.0025%, respectively. PEG 3350 was shown to be the best stabilizing agent, resulting in 109% of phytase activity from the initial crude extract remaining activity in after 90 days. 相似文献
398.
Variation in the XK, Kell blood group complex subunit–related family, member 4 (XKR4) gene on BTA14 was associated with rump fat thickness in a recent genome‐wide association study. This region is also of interest because it is known to show evidence of a signature of population genetic selection. In this study, additional variation in this gene was genotyped in a sample of a total of 1283 animals of the Belmont Red (BEL) and Santa Gertrudis (SGT) breeds. The SNP rs41724387 was significantly (P < 0.001) associated with rump fat thickness and explained 5.9% of the genetic variance for the trait in this sample. Using the 4466 genotypes for the SNP rs42646708 from several data sets to estimate effects in seven breeds, this relatively large quantitative trait locus effect appears to be a result of the variation in indicine and taurine–indicine composite cattle. However, the only DNA variant found in Brahman cattle that altered the predicted amino acid sequence of XKR4 was not associated with rump fat thickness. This suggests that causative mutations lie outside the coding sequence of this gene. 相似文献
399.
400.
Giselle Maria Maciel Luciana Porto de Souza Vandenberghe Ricardo Cancio Fendrich Bianca Eli Della Bianca Charles Windson Isidoro Haminiuk Carlos Ricardo Soccol 《Biotechnology and Bioprocess Engineering》2009,14(6):748-755
Xylanases are glycosidases mainly responsible for the hydrolysis of β-1,4 linkages in xylan. Xylanase was produced in this
work by solid-state fermentation using agro industrial residues with Aspergillus niger strain, which was screened through qualitative and quantitative methods. Extraction processes with different solvents were
evaluated. Solvent volume, time, and agitation speed (shaker) were optimized using statistical designs. Drying studies of
the solid fermented material were also conducted in a laboratory oven where the following conditions were applied: 42°C and
50°C for 20 h and 80°C for 1 h; 50°C and 75°C for 6 and 3 h, respectively. Best extraction conditions were 37 mL of solvent
composed by NaCl solution (0.9%) with Tween 80 (0.1%) in 3 g of cultured material with agitation at 133 rpm in shaker for
4 min. Highest xylanase activity was 2,327 IU/gdm. The drying at 42°C for 20 h provided a better maintenance of xylanase activity
(58% of xylanase activity). 相似文献