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161.
Involved in the ongoing debate is the speculation that aluminium is somehow toxic for neurons. Glial cells cope up to protect
neurons from this toxic insult by maintaining the glutathione homeostasis. Of late newer and newer roles of glial cells have
been depicted. The present work looks into the other regulatory mechanisms that show the glial cells response to pro-oxidant
effects of aluminium exposure. In the present investigation we have evaluated the inflammatory responses of the glial cells
as well as HSP70-induction during aluminium exposure. Further, the protective role of curcumin is also evaluated. Aluminium
was administered by oral gavage at a dose level of 100 mg/kg b.wt/day for a period of 8 weeks. Curcumin was administered i.p.
at a dose of 50 mg/kg b.wt./day on alternate days. Enhanced gene and protein expression of HSP70 in the glial fractions of
the aluminium exposed animals as compared to the corresponding neuronal population. Aluminium exposure resulted in a significant
increase in the NF-κB and TNF-α expression suggesting inflammatory responses. In the conjunctive treatment group of aluminium
and curcumin exposure marked reduction in the gene and protein expression of NF-κB and TNF-α was observed. This was further
reflected in histopathological studies showing no evidence of inflammation in conjunctive group as compared to aluminium treatment.
From the present study, it can be concluded that curcumin has a potential anti-inflammatory action and can be exploited in
other toxicological conditions also. 相似文献
162.
Hong-Yi Zhou Shao-Rui Chen Hee-Sun Byun Hong Chen Li Li Hee-Dong Han Gabriel Lopez-Berestein Anil K. Sood Hui-Lin Pan 《The Journal of biological chemistry》2012,287(40):33853-33864
Loss of synaptic inhibition by γ-aminobutyric acid and glycine due to potassium chloride cotransporter-2 (KCC2) down-regulation in the spinal cord is a critical mechanism of synaptic plasticity in neuropathic pain. Here we present novel evidence that peripheral nerve injury diminishes glycine-mediated inhibition and induces a depolarizing shift in the reversal potential of glycine-mediated currents (Eglycine) in spinal dorsal horn neurons. Blocking glutamate N-methyl-d-aspartate (NMDA) receptors normalizes synaptic inhibition, Eglycine, and KCC2 by nerve injury. Strikingly, nerve injury increases calcium-dependent calpain activity in the spinal cord that in turn causes KCC2 cleavage at the C terminus. Inhibiting calpain blocks KCC2 cleavage induced by nerve injury and NMDA, thereby normalizing Eglycine. Furthermore, calpain inhibition or silencing of μ-calpain at the spinal level reduces neuropathic pain. Thus, nerve injury promotes proteolytic cleavage of KCC2 through NMDA receptor-calpain activation, resulting in disruption of chloride homeostasis and diminished synaptic inhibition in the spinal cord. Targeting calpain may represent a new strategy for restoring KCC2 levels and tonic synaptic inhibition and for treating chronic neuropathic pain. 相似文献
163.
Devinder Kaur Ram K. Ogra Amita Bhattacharya Anil Sood 《In vitro cellular & developmental biology. Plant》2012,48(1):120-126
A liquid paraffin overlay (LPO) was used for storage of rapidly multiplying somatic embryos of Dendrocalamus hamiltonii under slow-growth conditions. Slow growth was associated with changes in sugar metabolism. In rapidly growing embryogenic
tissues, a sharp decline in starch and non-reducing sugars indicated rapid utilization of starch. In contrast, under slow-growth
conditions in somatic embryos stored under LPO, a gradual decline in starch indicated its slower utilization. As a result,
growth of somatic embryos under LPO was suppressed and subculturing was not required. Following retrieval from growth under
LPO after 30, 90, 180, 270, and 365 d of storage, the somatic embryos showed high recovery and germination (79.78%, 77.49%,
71.22%, 67.13%, and 59.99%, respectively) and were able to proliferate following transfer to Murashige and Skoog’s (Physiol.
Plant. 15:473–497, 1962) medium containing 1 mgl−1 BAP and 2% sucrose. The study provides useful information on in vitro storage of embryogenic tissue of D. hamiltonii. 相似文献
164.
Stephan DA Howell GR Teslovich TM Coffey AJ Smith L Bailey-Wilson JE Malechek L Gildea D Smith JR Gillanders EM Schleutker J Hu P Steingruber HE Dhami P Robbins CM Makalowska I Carpten JD Sood R Mumm S Reinbold R Bonner TI Baffoe-Bonnie A Bubendorf L Heiskanen M Kallioneimi OP Baxevanis AD Joseph SS Zucchi I Burk RD Isaacs W Ross MT Trent JM 《Genomics》2002,79(1):41-50
165.
Sood R Domanov Y Pietiäinen M Kontinen VP Kinnunen PK 《Biochimica et biophysica acta》2008,1778(4):983-996
Pursuing the molecular mechanisms of the concentration dependent cytotoxic and hemolytic effects of the human antimicrobial peptide LL-37 on cells, we investigated the interactions of this peptide with lipids using different model membranes, together with fluorescence spectroscopy for the Trp-containing mutant LL-37(F27W). Minimum concentrations inhibiting bacterial growth and lipid interactions assessed by dynamic light scattering and monolayer penetration revealed the mutant to retain the characteristics of native LL-37. Although both LL-37 and the mutant intercalated effectively into zwitterionic phosphatidylcholine membranes the presence of acidic phospholipids caused augmented membrane binding. Interestingly, strongly attenuated intercalation of LL-37 into membranes containing both cholesterol and sphingomyelin (both at X=0.3) was observed. Accordingly, the distinction between target and host cells by LL-37 is likely to derive from i) acidic phospholipids causing enhanced association with the former cells as well as ii) from attenuated interactions with the outer surface of the plasma membrane of the peptide secreting host, imposed by its high content of cholesterol and sphingomyelin. Our results further suggest that LL-37 may exert its antimicrobial effects by compromising the membrane barrier properties of the target microbes by a mechanism involving cytotoxic oligomers, similarly to other peptides forming amyloid-like fibers in the presence of acidic phospholipids. 相似文献
166.
Genetic diversity among and within cultured cyanobionts of diverse species of <Emphasis Type="Italic">Azolla</Emphasis> 总被引:1,自引:1,他引:0
The cyanobionts isolated from 10 Azolla accessions belonging to 6 species (Azolla mexicana, A. microphylla, A. rubra, A. caroliniana, A. filiculoides, A. pinnata) were cultured under laboratory conditions and analyzed on the basis of whole cell protein profiles and molecular marker dataset generated using repeat sequence primers (STRR(mod) and HipTG). The biochemical and molecular marker profiles of the cyanobionts were compared with those of the free-living cyanobacteria and symbiotic Nostoc strains from Anthoceros sp., Cycas sp. and Gunnera monoika. Cluster analysis revealed the genetic diversity among the selected strains, and identified 3 distinct clusters. Group 1 included cyanobionts from all the 10 accessions of Azolla, group 2 comprised all the symbiotic Nostoc strains, while group 3 included the free-living cyanobacteria belonging to the genera Nostoc and Anabaena. The interrelationships among the Azolla cyanobionts were further revealed by principal component analysis. Cyanobionts from A. caroliniana-A. microphylla grouped together while cyanobionts associated with A. mexicana-A. filiculoides along with A. pinnata formed another group. A. rubra cyanobionts had intermediate relationship with both the subgroups. This is the first study analyzing the diversity existing among the cultured cyanobionts of diverse Azolla species through the use of biochemical and molecular profiles and also the genetic distinctness of these free-living cyanobionts as compared to cyanobacterial strains of the genera Anabaena and Nostoc. 相似文献
167.
An important objective of computational protein design is the generation of high affinity peptide inhibitors of protein-peptide interactions, both as a precursor to the development of therapeutics aimed at disrupting disease causing complexes, and as a tool to aid investigators in understanding the role of specific complexes in the cell. We have developed a computational approach to increase the affinity of a protein-peptide complex by designing N or C-terminal extensions which interact with the protein outside the canonical peptide binding pocket. In a first in silico test, we show that by simultaneously optimizing the sequence and structure of three to nine residue peptide extensions starting from short (1-6 residue) peptide stubs in the binding pocket of a peptide binding protein, the approach can recover both the conformations and the sequences of known binding peptides. Comparison with phage display and other experimental data suggests that the peptide extension approach recapitulates naturally occurring peptide binding specificity better than fixed backbone design, and that it should be useful for predicting peptide binding specificities from crystal structures. We then experimentally test the approach by designing extensions for p53 and dystroglycan-based peptides predicted to bind with increased affinity to the Mdm2 oncoprotein and to dystrophin, respectively. The measured increases in affinity are modest, revealing some limitations of the method. Based on these in silico and experimental results, we discuss future applications of the approach to the prediction and design of protein-peptide interactions. 相似文献
168.
Changes in plant architecture have been central to the domestication of wild species. Tillering or the degree of branching
determines shoot architecture and is a key component of grain yield and/or biomass. Previously, a tiller inhibition mutant with monoculm phenotype was isolated and the mutant gene (tin3) was mapped in the distal region of chromosome arm 3AmL of Triticum monococcum. As a first step towards isolating a candidate gene for tin3, the gene was mapped in relation to physically mapped expressed sequence tags (ESTs) and sequence tag site (STS) markers
developed based on synteny with rice. In addition, we investigated the relationship of the wheat region containing tin3 with the corresponding region in rice by comparative genomic analysis. Wheat ESTs that had been previously mapped to deletion
bins provided a useful framework to identify closely related rice sequences and to establish the most likely syntenous region
in rice for the wheat tin3 region. The tin3 gene was mapped to a 324-kb region spanned by two overlapping bacterial artificial chromosomes (BACs) of rice chromosome
arm 1L. Wheat–rice synteny was exceptionally high at the tin3 region despite being located in the high-recombination, gene-rich region of wheat. Identification of tightly linked flanking
EST and STS markers to the tin3 gene and its localization to highly syntenic rice BACs will assist in the future development of a high-resolution map and
map-based cloning of the tin3 gene.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
169.
Changes in the concentrations of endogenous polyamines and ethylene were determined in two diverse species of rose viz. Rosa damascena and Rosa bourboniana during post-harvest periods. At full bloom, the concentrations of free putrescine was significantly higher than rest of the
polyamines, i.e. spermine and spermidine in both the species. The concentrations of all the polyamines decreased during subsequent
periods upto 48 h after full bloom. Similar situation was also observed in conjugated fraction but in bound fraction, during
full bloom, the concentration of spermine was higher than rest of the polyamines. In both the species, ethylene showed higher
levels during full bloom with maximum in R. damascena, which increased, during post-harvest periods. The possible significance of polyamines, ethylene and their interactions is
discussed during post-harvest periods in flowers. 相似文献
170.
Yogesh B. Surase Kirandeep Samby Sagar R. Amale Ruchi Sood Kedar P. Purnapatre Pawan K. Pareek Biswajit Das Kamna Nanda Subodh Kumar Ashwani K. Verma 《Bioorganic & medicinal chemistry letters》2017,27(15):3454-3459
A non-diaryl quinoline scaffold 6,7-dihydropyrazolo[1,5-a]pyrazin-4-one was identified by screening of diverse set of compounds against M. smegmatis ATP synthase. Herein, we disclose our efforts to develop the structure activity relationship against Mycobacterium tuberculosis (Mtb.H37Rv strain) around the identified hit 1. A scaffold hopping approach was used to identify compounds 14a, 14b and 24a with improved activity against MTb.H37Rv. 相似文献