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111.
Ceramidases are a group of enzymes that degrade pro-inflammatory ceramide by cleaving a fatty acid to form anti-inflammatory sphingosine lipid. Thus far, acid, neutral and alkaline ceramidase isozymes have been described. However, the expression patterns of ceramidase isoforms as well as their role in periodontal disease pathogenesis remain unknown. In this study, expression patterns of ceramidase isoforms were quantified by real-time PCR and immunohistochemistry in gingival samples of patients with periodontitis and healthy subjects, as well as in EpiGingivalTM-3D culture and OBA-9 gingival epithelial cells both of which were stimulated with or without the presence of live Porphyromonas gingivalis (ATCC 33277 strain). A significantly lower level of acid ceramidase expression was detected in gingival tissues from periodontal patients compared to those from healthy subjects. In addition, acid-ceramidase expression in EpiGingival? 3D culture and OBA-9?cells was suppressed by stimulation with P. gingivalis in vitro. No significant fluctuation was detected for neutral or alkaline ceramidases in either gingival samples or cell cultures. Next, to elucidate the role of acid ceramidase in P. gingivalis-induced inflammation in vitro, OBA-9?cells were transduced with adenoviral vector expressing the human acid ceramidase (Ad-ASAH1) gene or control adenoviral vector (Ad-control). In response to stimulation with P. gingivalis, ASAH1-over-expressing OBA-9?cells showed significantly lower mRNA expressions of caspase-3 as well as the percentage of Annexin V-positive cells, when compared with OBA-9?cells transduced with Ad-control vector. Furthermore, in response to stimulation with P. gingivalis, ASAH1-over-expressing OBA-9?cells produced less TNF-α, IL-6, and IL1β pro-inflammatory cytokines than observed in OBA-9?cells transduced with Ad-control vector. Collectively, our data show the novel discovery of anti-inflammatory and anti-apoptotic effects of acid ceramidase in host cells exposed to periodontal bacteria, and the attenuation of the expression of host-protective acid ceramidase in periodontal lesions.  相似文献   
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A thermodynamically and kinetically simple picture of protein folding envisages only two states, native (N) and unfolded (U), separated by a single activation free energy barrier, and interconverting by cooperative two‐state transitions. The folding/unfolding transitions of many proteins occur, however, in multiple discrete steps associated with the formation of intermediates, which is indicative of reduced cooperativity. Furthermore, much advancement in experimental and computational approaches has demonstrated entirely non‐cooperative (gradual) transitions via a continuum of states and a multitude of small energetic barriers between the N and U states of some proteins. These findings have been instrumental towards providing a structural rationale for cooperative versus noncooperative transitions, based on the coupling between interaction networks in proteins. The cooperativity inherent in a folding/unfolding reaction appears to be context dependent, and can be tuned via experimental conditions which change the stabilities of N and U. The evolution of cooperativity in protein folding transitions is linked closely to the evolution of function as well as the aggregation propensity of the protein. A large activation energy barrier in a fully cooperative transition can provide the kinetic control required to prevent the accumulation of partially unfolded forms, which may promote aggregation. Nevertheless, increasing evidence for barrier‐less “downhill” folding, as well as for continuous “uphill” unfolding transitions, indicate that gradual non‐cooperative processes may be ubiquitous features on the free energy landscape of protein folding.  相似文献   
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Diabetes is a major problem in the world. The proteins became modified during glycation after reacting with the reducing sugars (e.g. D-glucose) via non-enzymatic pathways. The glycated analogue of human serum albumin (HSA) has been characterized with the help of multi-spectroscopic methods. It has been observed that six glucose molecules can bind covalently to HSA under experimental condition. The binding affinity of the modified HSA towards the dietary polyphenols has been estimated using UV–vis and fluorescence spectroscopic techniques. The binding constant values of the ligands were found to decrease after the modification of HSA.  相似文献   
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Waste management and declining soil fertility are the two main issues experienced by all developing nations, like India. Nowadays, agricultural utilization of Municipal Solid Waste (MSW) is one of the most promising and cost effective options for managing solid waste. It is helpful in solving two current burning issues viz. soil fertility and MSW management. However, there is always a potential threat because MSW may contain pathogens and toxic pollutants. Therefore, much emphasis has been paid to composting of MSW in recent years. Application of compost from MSW in agricultural land helps in ameliorating the soil’s physico-chemical properties. Apart from that it also assists in improving biological response of cultivated land. Keeping the present situation in mind, this review critially discusses the current scenario, agricultural utilization of MSW compost, role of soil microbes and soil microbial response on municipal solid waste compost application.  相似文献   
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BackgroundInvasive lobular carcinoma (ILC) comprises approximately ~10–20% of breast cancers. In general, multifocal/multicentric (MF/MC) breast cancer has been associated with an increased rate of regional lymph node metastases. Tumor heterogeneity between foci represents a largely unstudied source of genomic variation in those rare patients with MF/MC ILC.MethodsWe characterized gene expression and copy number in 2 or more foci from 11 patients with MF/MC ILC (all ER+, HER2-) and adjacent normal tissue. RNA and DNA were extracted from 3x1.5mm cores from all foci. Gene expression (730 genes) and copy number (80 genes) were measured using Nanostring PanCancer and Cancer CNV panels. Linear mixed models were employed to compare expression in tumor versus normal samples from the same patient, and to assess heterogeneity (variability) in expression among multiple ILC within an individual.Results35 and 34 genes were upregulated (FC>2) and down-regulated (FC<0.5) respectively in ILC tumor relative to adjacent normal tissue, q<0.05. 9/34 down-regulated genes (FIGF, RELN, PROM1, SFRP1, MMP7, NTRK2, LAMB3, SPRY2, KIT) had changes larger than CDH1, a hallmark of ILC. Copy number changes in these patients were relatively few but consistent across foci within each patient. Amplification of three genes (CCND1, FADD, ORAOV1) at 11q13.3 was present in 2/11 patients in both foci. We observed significant evidence of within-patient between-foci variability (heterogeneity) in gene expression for 466 genes (p<0.05 with FDR 8%), including CDH1, FIGF, RELN, SFRP1, MMP7, NTRK2, LAMB3, SPRY2 and KIT.ConclusionsThere was substantial variation in gene expression between ILC foci within patients, including known markers of ILC, suggesting an additional level of complexity that should be addressed.  相似文献   
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Fibroblast growth factors (Fgfs) and their receptors (Fgfr) are expressed in the developing and adult CNS. Previous studies demonstrated a decrease in cortical interneurons and locomotor hyperactivity in mice with a conditional Fgfr1 deletion generated in radial glial cells during midneurogenesis (Fgfr1f/f;hGfapCre+). Here, we report earlier and more extensive inactivation of Fgfr1 in neuroepithelial cells of the CNS (Fgfr1f/f;NesCre+). Similar to findings in Fgfr1f/f;hGfapCre+ mice, parvalbumin positive (PV+) cortical interneurons are also decreased in the neocortex of Fgfr1f/f;NesCre+ mice when compared to control littermates (Fgfr1f/f). Fgfr1f/f;NesCre+ embryos do not differ from controls in the initial specification of GABAergic cells in the ganglionic eminence (GE) as assessed by in situ hybridization for Dlx2, Mash1 and Nkx2. Equal numbers of GABAergic neuron precursors genetically labeled with green fluorescent protein (GFP) were observed at P0 in Fgfr1f/f;hGfapCre+;Gad1-GFP mutant mice. However, fewer GFP+ and GFP+/PV+ interneurons were observed in these mutants at adulthood, indicating that a decrease in cortical interneuron markers is occurring postnatally. Fgfr1 is expressed in cortical astrocytes in the postnatal brain. To test whether the astrocytes of mice lacking Fgfr1 are less capable of supporting interneurons, we co-cultured wild type Gad1-GFP+ interneuron precursors isolated from the medial GE (MGE) with astrocytes from Fgfr1f/f control or Fgfr1f/f;hGfapCre+ mice. Interneurons grown on Fgfr1 deficient astrocytes had small soma size and fewer neurites per cell, but no differences in cell survival. Decreased soma size of Gad67 immunopositive interneurons was also observed in the cortex of adult Fgfr1f/f;NesCre+ mice. Our data indicate that astrocytes from Fgfr1 mutants are impaired in supporting the maturation of cortical GABAergic neurons in the postnatal period. This model may elucidate potential mechanisms of impaired PV interneuron maturation relevant to neuropsychiatric disorders that develop in childhood and adolescence.  相似文献   
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UL21 is a conserved protein in the tegument of alphaherpesviruses and has multiple important albeit poorly understood functions in viral replication and pathogenesis. To provide a roadmap for exploration of the multiple roles of UL21, we determined the crystal structure of its conserved N-terminal domain from herpes simplex virus 1 to 2.0-Å resolution, which revealed a novel sail-like protein fold. Evolutionarily conserved surface patches highlight residues of potential importance for future targeting by mutagenesis.  相似文献   
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An efficient and improved method for in vitro propagation of mature tree of Dalbergia sissoo, an ecologically and commercially important timber yielding species, has been developed through axillary shoot proliferation. Bud breaking occurred from nodal shoot segments derived from rejuvenated shoots produced during early spring from a 20–25-year-old lopped tree, on MS medium containing 8.88 μM benzylaminopurine (BAP). Multiple shoots differentiated (20–21shoots/node) on re-culture of explants on half-strength agar gelled amended MS medium with a combination of 2.22 μM of BAP and 0.002 μM of thidiazuron (TDZ) with 1.0 mM each of Ca(NO3)2, K2SO4, KCl, and NH4(SO4)2. The maximum shoot multiplication (29–30 shoots/node) was achieved on subculturing in the above mentioned but liquid medium. Furthermore, the problem of shoot tip necrosis and defoliation observed on solid medium were overcome by the use of liquid medium. Ex vitro rooting was achieved on soilrite after basal treatment of microshoots with 984 μM of indole-3-butyric acid (IBA) for 2 min. About 90 % microshoots were rooted on soilrite within 2–3 weeks under the greenhouse conditions. From 20 nodal shoot segments, about 435 hardened plants were acclimatized and transplanted. This is the first report for rapid in vitro propagation of mature trees of D. sissoo on liquid medium followed by ex vitro rooting.  相似文献   
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