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51.
Gustavo C. Bressan Eduardo C. Moraes Adriana O. Manfiolli Tais M. Kuniyoshi Dario O. Passos Marcelo D. Gomes Jörg Kobarg 《Cellular & molecular biology letters》2009,14(4):657-669
The human SFRS9/SRp30c belongs to the SR family of splicing regulators. Despite evidence that members of this protein family
may be targeted by arginine methylation, this has yet to be experimentally addressed. In this study, we found that SFRS9 is
a target for PRMT1-mediated arginine methylation in vitro, and that it is immunoprecipitated from HEK-293 lysates by antibodies that recognize both mono- and dimethylated arginines.
We further observed that upon treatment with the methylation inhibitor Adox, the fluorescent EGFP-SFRS9 re-localizes to dot-like
structures in the cell nucleus. In subsequent confocal analyses, we found that EGFP-SFRS9 localizes to nucleoli in Adox-treated
cells. Our findings indicate the importance of arginine methylation for the subnuclear localization of SFRS9. 相似文献
52.
L. P. G. D’Arce C. L. Bassi A. L. Fachin G. A. S. Passos E. T. Sakamoto-Hojo 《Genetica》2009,136(3):471-478
Illegitimate V(D)J-recombination in lymphoid malignancies involves rearrangements in immunoglobulin or T-cell receptor genes,
and these rearrangements may play a role in oncogenic events. High frequencies of TRGV-BJ hybrid gene (rearrangement between
the TRB and TRG loci at 7q35 and 7p14-15, respectively) have been detected in lymphocytes from patients with ataxia telangiectasia
(AT), and also in patients with lymphoid malignancies. Although the TRGV-BJ gene has been described only in T-lymphocytes,
we previously detected the presence of TRGV-BJ hybrid gene in the genomic DNA extracted from SV40-transformed AT5BIVA fibroblasts
from an AT patient. Aiming to determine whether the AT phenotype or the SV40 transformation could be responsible for the production
of the hybrid gene by illegitimate V(D)J-recombination, DNA samples were extracted from primary and SV40-transformed (normal
and AT) cell lines, following Nested-PCR with TRGV- and TRBJ-specific primers. The hybrid gene was only detected in SV40-transformed
fibroblasts (AT-5BIVA and MRC-5). Sequence alignment of the cloned PCR products using the BLAST program confirmed that the
fragments corresponded to the TRGV-BJ hybrid gene. The present results indicate that the rearrangement can be produced in
nonlymphoid cells, probably as a consequence of the genomic instability caused by the SV40-transformation, and independently
of ATM gene mutation. 相似文献
53.
Lima CS Néri IA Lourenço GJ Faria IC Ribeiro JD Bertuzzo CS 《Genetics and molecular biology》2010,33(3):438-441
Xenobiotics can trigger degranulation of eosinophils and mast cells. In this process, the cells release several substances leading to bronchial hyperactivity, the main feature of atopic asthma (AA). GSTM1 and GSTT1 genes encode enzymes involved in the inactivation of these compounds. Both genes are polymorphic in humans and have a null variant genotype in which both the gene and corresponding enzyme are absent. An increased risk for disease in individuals with the null GST genotypes is therefore, but this issue is controversial. The aim of this study was to investigate the influence of the GSTM1 and GSTT1 genotypes on the occurrence of AA, as well as on its clinical manifestations. Genomic DNA from 86 patients and 258 controls was analyzed by polymerase chain reaction. The frequency of the GSTM1 null genotype in patients was higher than that found in controls (60.5% versus 40.3%, p = 0.002). In individuals with the GSTM1 null genotype the risk of manifested AA was 2.3-fold higher (95%CI: 1.4-3.7) than for others. In contrast, similar frequencies of GSTT1 null and combined GSTM1 plus GSTT1 null genotypes were seen in both groups. No differences in genotype frequencies were perceived in patients stratified by age, gender, ethnic origin, and severity of the disease. These results suggest that the inherited absence of the GSTM1 metabolic pathway may alter the risk of AA in southeastern Brazilian children, although this must be confirmed by further studies with a larger cohort of patients and age-matched controls from the distinct regions of the country. 相似文献
54.
55.
da Silva GN Evangelista AF Magalhães DA Macedo C Búfalo MC Sakamoto-Hojo ET Passos GA Salvadori DM 《Molecular biology reports》2011,38(6):4159-4170
Urinary bladder cancer is the fourth most common malignancy in the Western world. Transitional cell carcinoma (TCC) is the
most common subtype, accounting for about 90% of all bladder cancers. The TP53 gene plays an essential role in the regulation of the cell cycle and apoptosis and therefore contributes to cellular transformation
and malignancy; however, little is known about the differential gene expression patterns in human tumors that present with
the wild-type or mutated TP53 gene. Therefore, because gene profiling can provide new insights into the molecular biology of bladder cancer, the present
study aimed to compare the molecular profiles of bladder cancer cell lines with different TP53 alleles, including the wild type (RT4) and two mutants (5637, with mutations in codons 280 and 72; and T24, a TP53 allele encoding an in-frame deletion of tyrosine 126). Unsupervised hierarchical clustering and gene networks were constructed
based on data generated by cDNA microarrays using mRNA from the three cell lines. Differentially expressed genes related to
the cell cycle, cell division, cell death, and cell proliferation were observed in the three cell lines. However, the cDNA
microarray data did not cluster cell lines based on their TP53 allele. The gene profiles of the RT4 cells were more similar to those of T24 than to those of the 5637 cells. While the deregulation
of both the cell cycle and the apoptotic pathways was particularly related to TCC, these alterations were not associated with
the TP53 status. 相似文献
56.
Tatiana Alves Rigamonte Fernandes Wendel Batista da Silveira Flávia Maria Lopes Passos Tiago Domingues Zucchi 《Annals of microbiology》2014,64(3):1363-1369
Laccases have become desirable enzymes for application in many industrial processes. Nowadays, most of these enzymes are obtained from fungi. Among prospective studies for bacterial laccase genes, some have included actinomycetes, but only a few studies have characterized the enzyme produced. Thus, we have isolated a laccase-producing actinomycete from forest soil under restoration process and further aimed to characterize its produced enzyme. The isolate SB086 was assigned to the Streptomyces genus by a combination of phenotypical, chemical and phylogenetic properties. Our data indicate that the bacterium produces a thermotolerant laccase. The maximum activity was obtained in the pH range 4.0–5.0 and at 50 °C in reaction mixture containing 5 mM CuSO4; thermal stability was noted at 60 °C and 70 °C—a well-desired characteristic for industry. The active enzyme presented a high molecular mass (over 100 kDa) and was less sensitive to inhibition by metal ions than generally described for bacterial laccases. Our findings support in silico data of bacterial laccase secretion, and reinforce the view that actinomycetes may be a rich source of laccase for industrial application. 相似文献
57.
Danon Clemes Cardoso Silvia das Gra?as Pompolo Maykon Passos Cristiano Mara Garcia Tavares 《PloS one》2014,9(1)
Among insect taxa, ants exhibit one of the most variable chromosome numbers ranging from n = 1 to n = 60. This high karyotype diversity is suggested to be correlated to ants diversification. The karyotype evolution of ants is usually understood in terms of Robertsonian rearrangements towards an increase in chromosome numbers. The ant genus Mycetophylax is a small monogynous basal Attini ant (Formicidae: Myrmicinae), endemic to sand dunes along the Brazilian coastlines. A recent taxonomic revision validates three species, Mycetophylax morschi, M. conformis and M. simplex. In this paper, we cytogenetically characterized all species that belongs to the genus and analyzed the karyotypic evolution of Mycetophylax in the context of a molecular phylogeny and ancestral character state reconstruction. M. morschi showed a polymorphic number of chromosomes, with colonies showing 2n = 26 and 2n = 30 chromosomes. M. conformis presented a diploid chromosome number of 30 chromosomes, while M. simplex showed 36 chromosomes. The probabilistic models suggest that the ancestral haploid chromosome number of Mycetophylax was 17 (Likelihood framework) or 18 (Bayesian framework). The analysis also suggested that fusions were responsible for the evolutionary reduction in chromosome numbers of M. conformis and M. morschi karyotypes whereas fission may determines the M. simplex karyotype. These results obtained show the importance of fusions in chromosome changes towards a chromosome number reduction in Formicidae and how a phylogenetic background can be used to reconstruct hypotheses about chromosomes evolution. 相似文献
58.
Wagner Serra e Silva Filho Renato C. V. Casarin Eduardo L. Nicolela Junior Humberto M. Passos Ant?nio W. Sallum Reginaldo B. Gon?alves 《PloS one》2014,9(10)
Background and Objective
The immune and infectious alterations occurring in periodontitis have been shown to alter the development and severity of cardiovascular disease. One of these relationships is the translocation of oral bacteria to atheroma plaques, thereby promoting plaque development. Thus, the aim of this study was to assess, by 16s cloning and sequencing, the microbial diversity of the subgingival environment and atheroma plaques of patients concomitantly suffering from periodontitis and obstructive coronary artery atherosclerosis (OCAA).Methods
Subgingival biofilm and coronary balloons used in percutaneous transluminal coronary angioplasty were collected from 18 subjects presenting with generalized moderate to severe periodontitis and OCAA. DNA was extracted and the gene 16S was amplified, cloned and sequenced.Results
Significant differences in microbial diversity were observed between both environments. While subgingival samples mostly contained the phylum Firmicutes, in coronary balloons, Proteobacteria (p<0.05) was predominant. In addition, the most commonly detected genera in coronary balloons were Acinetobacter, Alloprevotella, Pseudomonas, Enterobacter, Sphingomonas and Moraxella, while in subgingival samples Porphyromonas, Filifactor, Veillonella, Aggregatibacter and Treponema (p<0.05) were found. Interestingly, 17 identical phylotypes were found in atheroma and subgingival samples, indicating possible bacterial translocation between periodontal pockets and coronary arteries.Conclusion
Periodontal pockets and atheromatous plaques of cardiovascular disease patients can present similarities in the microbial diversity. 相似文献59.
60.
P. A. Sanchez Podlech M. Furia Luna Paulo R. Jerke Carlos A. C. de Souza Neto Rogério F. dos Passos Ozair Souza Walter Borzani 《Biotechnology letters》1990,12(7):531-534
Summary A Monod-like equation correlates the lactic acid productivity and the volume fraction of inoculum in semicontinuous fermentation of whey byLactobacillus bulgaricus. The volume of the inoculum varied from 10% to 80% of the reactor working volume.Nomenclature N
number of fermentation cycles after the first fermentation
- P
lactic acid productivity
- Sw
average total sugars concentration of the whey as lactose (the standard deviation is indicated)
- T
average fermentation time (the standard deviation is indicated)
- Va
average total consumption of NH4OH solution (the standard deviation is indicated)
- Vi
volume of recently fermented medium used as inoculum of the next fermentation cycle
- Vw
volume of whey added to the reactor at the beginning of each fer mentation cycle
-
volume fraction of inoculum=Vi/(Vi+Vw) 相似文献