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131.
132.
Pramod S. Anju M. Rajesh H. Thulaseedharan A. Rao Karumanchi S. 《Journal of Plant Growth Regulation》2022,41(1):404-416
Journal of Plant Growth Regulation - Plant growth regulators play a key role in cell wall structure and chemistry of woody plants. Understanding of these regulatory signals is important in advanced... 相似文献
133.
The reticulocytes and the ageing red blood cells (RBCs) namely young (Y), middle-aged (M) and old RBCs (O) of female Wistar
rats from different groups such as control animals (C), controls treated with vanadate (C + V), alloxan-induced diabetic (D),
diabetic-treated with insulin (D + I) and vanadate (D + V), were fractionated on a percoll/BSA gradient. The following enzymes
were measured-hexokinase (HK), glutathione peroxidase (GSH-Px), glutathione reductase (GSSG-R), glutathione-s-transferase
(GST), alanine aminotransferase ΜlaAT), aspartate aminotransferase ΜsAT) and arginase in the hemolysates of all the RBCs fractions.
Decreases in the activity of HK and AsAT by about 70%, arginase and GSH-Px by 30% in old RBCs were observed in comparison
to reticulocytes of control animals. Increases in the activity of GSSG-R by 86%, AlaAT by more than 400% and GST by 70% were
observed in old RBCs in comparison to reticulocytes of control animals.
Alloxan diabetic animals showed a further decrease in the activities of HK in Y RBCs by 37%, M RBCs by 39% and O RBCs by 32%,
GSH-Px activity in Y RBCs by 13%, M RBCs by 20% and O RBCs by 33% and GST activity in Y RBCs by 14%, M RBCs by 42% and O RBCs
by 60% in comparison to their corresponding cells of control animals. An increase in the activity of all the enzymes studied
was also observed in reticulocytes of diabetic animals in comparison to reticulocytes of controls. The GSSG-R activity was
found to be increased in Y RBCs by 49%, M RBCs by 67% and O RBCs by 64% as compared to the corresponding age-matched cells
of control animals. The activity of arginase also decreased in Y RBCs by about10%, M RBCs by 20% and O RBCs by 30% in comparison
to the age-matched cells of control animals. A decrease in the activity of AsAT in Y and M RBCs by 30%, and O RBCs by 25%
was observed in diabetic animals in comparison to the agematched cells of control animals. The activity of AlaAT was found
to be decreased by more than 10% in Y and M RBCs and 25% in O RBCs of diabetic animals in comparison to the age-matched cells
of control animals.
Insulin administration to diabetic animals reversed the altered enzyme activity to control values. Vanadate treatment also
reversed the enzyme levels except for that of GST in old cells 相似文献
134.
Biological treatment of textile dye acid violet-17 by bacterial consortium in an up-flow immobilized cell bioreactor 总被引:1,自引:0,他引:1
AIMS: To develop a cost effective and efficient biological treatment process for small scale textile processing industries (TPI) releasing untreated effluents containing intense coloured Acid violet-17 (AV-17), a triphenyl methane (TPM) group textile dye. METHODS AND RESULTS: The samples collected from effluent disposal sites of TPI were used for selective enrichment of microbial populations capable of degrading/decolourizing AV-17. A consortium of five bacterial isolates was used to develop an up-flow immobilized cell bioreactor for treatment of feed containing AV-17. The bioreactor, operating at a flow rate of 6 ml x h(-1), resulted in 91% decolourization of 30 mg AV-17/l with 94.3 and 95.7% removal of biochemical oxygen demand and chemical oxygen demand of the feed. Comparison of the input and output of the bioreactor by UV-visible, thin layer chromatography and (1)H-nuclear magnetic resonance spectroscopy indicates conversion of the parent dye into unrelated metabolic intermediates. SIGNIFICANCE: These results will form a basis for developing 'on-site' treatment system for TPI effluents to achieve decolourization and degradation of residual dyes. 相似文献
135.
Morphological, developmental and antimetabolite-resistant mutants of T. lanuginosus were characterized and used for screening with the aim to develop constitutive alpha-amylase-hyperproducing strains. The protoplast fusion of two spontaneous mutants of T. lanuginosus, characterized as asporulating and resistant to 2-deoxy-D-glucose (2DG), resulted in sporulating, 2DG sensitive heterokaryotic fusants. A recombinant haploid strain F64fB developed there from produced alpha-amylase constitutively in glucose-containing medium. Constitutive alpha-amylase-hyperproducing mutant (III8) obtained after cyclic mutagenesis and screening yielded approximately 20 fold more alpha-amylase in a glycerol-containing medium than the wild strain. 相似文献
136.
Role of tumor necrosis factor receptors in regulating CD8 T-cell responses during acute lymphocytic choriomeningitis virus infection
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The role of tumor necrosis factor (TNF) in regulating various phases of the antiviral T-cell response is incompletely understood. Additionally, despite strong evidence ascribing a role for TNF in protecting against T-cell-dependent autoimmunity, the underlying mechanisms are still obscure. To address these issues, we have investigated the role of tumor necrosis factor receptors (TNFRs) I (p55R) and II (p75R) in regulating CD8 T-cell responses to lymphocytic choriomeningitis virus (LCMV) with wild-type, p55R-deficient (p55(-/-)), p75R-deficient (p75(-/-)), and p55R- and p75R-deficient (DKO) mice. Loss of p55R increased the number of memory CD8 T cells to only one of the two immunodominant epitopes, and p75R deficiency had a minimal impact on the T-cell response to LCMV. Strikingly, deficiency of both p55R and p75R had a more dramatic effect on the LCMV-specific CD8 T-cell response; in the DKO mice, as a sequel to enhanced expansion and a reduction in contraction of CD8 T cells, there was a substantial increase in the number of memory CD8 T cells (specific to the two immunodominant epitopes). While the majority of LCMV-specific memory CD8 T cells in wild-type mice were CD62Lhi CCR7hi (central memory), a major proportion of memory CD8 T cells in DKO mice were CD62Llo CCR7hi. TNFR deficiency did not affect the proliferative renewal of memory CD8 T cells. Taken together, these data suggested that TNFRs p55R and p75R have overlapping roles in downregulating CD8 T-cell responses and establishment of immune homeostasis during an acute viral infection. 相似文献
137.
138.
Banerjee I Nagee A Mukhopadhyaya PN Kothari IL 《Roumanian archives of microbiology and immunology》2004,63(3-4):223-233
A gram negative chemolithotrophic bacterium (RPI) with facultative mode of nutrition was isolated from the soil. Enzymological studies confirmed presence of Thiosulphate oxidase, sulphite oxidase and Rhodanese, all of which play role in sulfur metabolism pathway. A set of degenerate oligonucleotide primer pairs was used for thermal amplification of a major part of the coding region of the Cytochrome c gene locus of this bacterium. Nucleotide and translated amino acid sequence revealed the gene to be a diheme Cytochrome c, different from the monoheme Cytochrome c observed in Chloribium limicola, a photosynthetic green sulfur bacterium. Significant homology at the nucleotide level could be detected only with Pseudoaminobacter salicylatoxidans. On the contrary, significant homology at the amino acid level was observed with Bradyrhizobium japonicum, Silicobacter pomeroyi apart from P. salicylatoxidans. This is possibly because of codon degeneracy observed within the diverse members of chemolithotrophs. Greater homology at amino acid level with P. salicylatoxidans and B. japonicum compared to that with P. denitrificans hint at possibly grouping of RP1 with the Rhizobium-Agrobacterium sub group of alpha Proteobacteria. 相似文献
139.
Magnitude of functional CD8+ T-cell responses to the gag protein of human immunodeficiency virus type 1 correlates inversely with viral load in plasma 总被引:8,自引:0,他引:8
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Edwards BH Bansal A Sabbaj S Bakari J Mulligan MJ Goepfert PA 《Journal of virology》2002,76(5):2298-2305
The importance of CD8+ T-cell responses in the control of human immunodeficiency virus type 1 (HIV-1) infection has been demonstrated, yet few studies have been able to correlate these responses with markers of HIV-1 disease progression. This study measured cell-mediated immune responses using peripheral blood mononuclear cells (PBMC) obtained from 27 patients with chronic HIV-1 infection, the majority of whom were off antiretroviral therapy. The ELISPOT assay was used to detect gamma interferon-secreting PBMC after stimulation with overlapping HIV-1 peptides spanning the Gag, Pol, Env, and Nef proteins in addition to the baculovirus-derived p24 and gp160 proteins. All volunteers had responses to at least one HIV-1-specific peptide. All but one of the subjects (96%) responded to the Gag peptide pool, and 86% responded to the Pol and/or Nef peptide pools. The magnitude and the breadth of T-cell responses directed to either the Gag or p24 peptide pools correlated inversely with viral load in plasma (r = -0.60, P < 0.001 and r = -0.52, P < 0.005, respectively) and directly with absolute CD4+ T-cell counts (r = 0.54, P < 0.01 and r = 0.39, P < 0.05, respectively) using the Spearman rank correlation test. Responses to the Pol and integrase peptide pools also correlated with absolute CD4+ T-cell counts (r = 0.45, P < 0.05 and r = 0.49, P < 0.01, respectively). No correlation with markers of disease progression was seen with specific T-cell responses directed toward the Env or Nef peptides. These data serve as strong evidence that major histocompatibility complex class I presentation of Gag peptides is an essential feature for any HIV-1 vaccine designed to elicit optimal CD8+ T-cell responses. 相似文献
140.
Nair MP Kandaswami C Mahajan S Chadha KC Chawda R Nair H Kumar N Nair RE Schwartz SA 《Biochimica et biophysica acta》2002,1593(1):29-36
Flavonoids are plant metabolites that are dietary antioxidants and exert significant anti-tumor, anti-allergic, anti-inflammatory and anti-viral effects. It is generally accepted that Th-1 derived cytokines such as IL-2, IFNgamma and IL-12 promote cellular immunity while Th-2 derived cytokines such as IL-4, IL-5, IL-6 exert negative immunoregulatory effects on cellular immunity while upregulating humoral immunity. The molecular mechanisms underlying the biological activities of flavonoids have not been elucidated. We hypothesize that the flavonoid, quercetin, exert significant anti-viral and anti-tumor effects possibly by modulating the production of Th-1 and Th-2 derived cytokines. Peripheral blood mononuclear cells (PBMC, 1 x 10(6) cells/ml) from normal subjects were cultured with different concentrations of quercetin (0.5-50 microM) for 24-72 h and supernates were quantitated for IFN-gamma and IL-4 by ELISA and antiviral activity of IFNgamma by bioassay. FACS analysis was done to determine the number of IFN-gamma and IL-4 positive cells and RT-PCR was done to quantitate gene expression. Quercetin significantly induces the gene expression as well as the production of Th-1 derived IFNgamma and the downregulates Th-2 derived IL-4 by normal PBMC. Further, quercetin treatment increased the phenotypic expression of IFNgamma cells and decreased IL-4 positive cells by FACS analysis, which corroborate with protein secretion and gene expression studies. These results suggest that the beneficial immuno-stimulatory effects of quercetin may be mediated through the induction of Th-1 derived cytokine, IFNgamma, and inhibition of Th-2 derived cytokine, IL-4. 相似文献