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101.
102.
Bharat Nareshkumar Shaik Mohammad Akbar Hari Chand Sharma Senigala K. Jayalakshmi Kuruba Sreeramulu 《Journal of bioenergetics and biomembranes》2018,50(1):21-32
Neonicotinoids have high agonistic affinity to insect nicotinic acetylcholine receptors (nAChR) and are frequently used as insecticides against most devastating lepidopteran insect pests. Imidacloprid influenced dose-dependent decline in the state III and IV respiration, respiration control index (RCI), and P/O ratios, in vitro and in vivo. The bioassay indicated its LD50 value to be 531.24 μM. The insecticide exhibited a dose-dependent inhibition on F0F1-ATPase and complex IV activity. At 600 μM, the insecticide inhibited 83.62 and 27.13% of F0F1-ATPase and complex IV activity, respectively, and induced the release of 0.26 nmoles/min/mg protein of cytochrome c. A significant dose- and time-dependent increase in oxidative stress was observed; at 600 μM, the insecticide correspondingly induced lipid peroxidation, LDH activity, and accumulation of H2O2 content by 83.33, 31.51 and 223.66%. The stress was the maximum at 48 h of insecticide treatment (91.58, 35.28, and 189.80%, respectively). In contrast, catalase and superoxide dismutase were reduced in a dose- and time-dependent manner in imidacloprid-fed larvae. The results therefore suggest that imidacloprid impedes mitochondrial function and induces oxidative stress in H. armigera, which contributes to reduced growth of the larvae along with its neurotoxic effect. 相似文献
103.
104.
We studied visual representation in the parietal cortex by recording whole-scalp neuromagnetic responses to luminance stimuli of varying eccentricities. The stimuli were semicircles (5.5 degrees in radius) presented at horizontal eccentricities from 0 degree to 16 degrees, separately in the right and left hemifields. All stimuli evoked responses in the contralateral occipital and medial parietal areas. The waveforms and distributions of the occipital responses varied with stimulus side (left, right) and eccentricity, whereas the parietal responses were remarkably similar to all stimuli. The equivalent sources of the parietal signals clustered within 1 cm3 in the medial parieto-occipital sulcus and did not differ significantly between the stimuli. The strength of the parietal activation remained practically constant with increasing stimulus eccentricity, suggesting that the visual areas in the parieto-occipital sulcus lack the enhanced foveal representation typical of most other visual areas. This result strengthens our previous suggestion that the medial parieto-occipital sulcus is the human homologue of the monkey V6 complex, characterized by, for example, lack of retinotopy and the absence of relative foveal magnification. 相似文献
105.
Hari H. P. Cohly James W. Stephens Michael F. Angel James C. Johnson Angel K. Markov 《In vitro cellular & developmental biology. Animal》1999,35(9):510-514
Summary Both smooth muscle cells and endothelial cells play an important role in vascular wound healing. To elucidate the role of
fructose-1, 6-diphosphate, cell proliferation and cell migration studies were performed with human endothelial cells and rat
smooth muscle cells. To mimic blood vessels, endothelial and smooth muscle cells were used in 1:10, 1:5, and 1:1 concentrations,
respectively, mimicking large-, mid-, and capillary-sized blood vessels. Cell migration was studied with fetal bovine serum-starved
cells. For cell proliferation assay, cells were plated at 30–50% confluency and then starved. The cells were incubated for
48 h with fructose-1, 6-diphosphate at (per ml) 10 mg, 1 mg, 500 μg, 250 μg, 100 μg, and 10 μg, pulsed with tritiated-thymidine
and incubated with 1 N NaOH for 30 min at room temperature, harvested, and counted. For migration assay, confluent cells were starved, wounded,
and incubated for 24 h with same concentrations of fructose-1, 6-diphosphate as in proliferation assay. The cells were fixed
and counted. Smooth muscle cell proliferation was inhibited by fructose-1, 6-diphosphate at 10 mg/ml. In the xenograft models
of 1:10, 1:5, and 1:1 fructose-1, 6-diphosphate inhibited proliferation at 10 mg/ml. In migration studies 10 mg fructose-1,
6-diphosphate per ml was inhibitory to both cell types. In large-, mid-, and capillary-sized blood vessels, fructose-1, 6-diphosphate
inhibited proliferation of both cell types at 10 mg/ml. At the individual cell level, fructose-1, 6-diphosphate is nonstimulatory
to proliferation of endothelial cells while inhibiting migration, and it acts on smooth muscle cells by inhibiting both proliferation
and migration. 相似文献
106.
Sinorhizobium fredii strain USDA208 is a nitrogen-fixing bacterium that forms nodules on roots of soybean and other legume plants. We previously found that the Tn5-containing mutant 208T3, which was derived from strain USDA208, is both deficient in production of exopolysaccharides and more competitive than the wild-type strain in competing against other rhizobia for nodulation of soybean. We now demonstrate that the transposon insertion of the mutant lies in a locus that is highly homologous to a portion of the exo region, which functions in exopolysaccharide biosynthesis by Sinorhizobium meliloti. We sequenced 2906 bp surrounding the insertion site and identified three genes: exoA, exoM, and exoO. The transposon lies within exoM, a glucosyl transferase. A cosmid containing exoHKLAMONP of S. meliloti restores exopolysaccharide production by mutant 208T3 to wild-type levels. Although exo mutants of S. meliloti are defective in their abilities to form indeterminate nodules, the capacities of mutant 208T3 and its wild-type parent to form such nodules on five legume species are indistinguishable. Thus the symbiotic function of exopolysaccharide in S. fredii appears to differ fundamentally from that in S. meliloti. 相似文献
107.
108.
Mohd. Quadir Siddiqui Rajan Kumar Choudhary Pankaj Thapa Neha Kulkarni Yogendra S. Rajpurohit Hari S. Misra 《Journal of biomolecular structure & dynamics》2017,35(14):3032-3042
Fanconi anemia complementation groups – I (FANCI) protein facilitates DNA ICL (Inter-Cross-link) repair and plays a crucial role in genomic integrity. FANCI is a 1328 amino acids protein which contains armadillo (ARM) repeats and EDGE motif at the C-terminus. ARM repeats are functionally diverse and evolutionarily conserved domain that plays a pivotal role in protein–protein and protein–DNA interactions. Considering the importance of ARM repeats, we have explored comprehensive in silico and in vitro approach to examine folding pattern. Size exclusion chromatography, dynamic light scattering (DLS) and glutaraldehyde crosslinking studies suggest that FANCI ARM repeat exist as monomer as well as in oligomeric forms. Circular dichroism (CD) and fluorescence spectroscopy results demonstrate that protein has predominantly α- helices and well-folded tertiary structure. DNA binding was analysed using electrophoretic mobility shift assay by autoradiography. Temperature-dependent CD, Fluorescence spectroscopy and DLS studies concluded that protein unfolds and start forming oligomer from 30°C. The existence of stable portion within FANCI ARM repeat was examined using limited proteolysis and mass spectrometry. The normal mode analysis, molecular dynamics and principal component analysis demonstrated that helix-turn-helix (HTH) motif present in ARM repeat is highly dynamic and has anti-correlated motion. Furthermore, FANCI ARM repeat has HTH structural motif which binds to double-stranded DNA. 相似文献
109.
Hari?Om?SinghEmail author Shruti?D?Marathe Sumitra?Nain Dharmesh?Samani Vijay?Nema Manisha?V?Ghate R?R?Gangakhedkar 《Journal of biosciences》2017,42(3):481-490
The pathogenesis of HIV-associated neurocognitive disorder (HAND) is modulated by host genetic susceptibility factors such as Matrix metalloproteinases (MMPs). Promoter polymorphism of MMP-1 and MMP-3 may modify the expression of the gene. Hence, we evaluated the association of MMP-1-16072G/1G and MMP-3-1612 5A/6A polymorphisms with development of HAND and the modulation of pathogenesis of HAND. We enrolled a total of 180 individuals, 50 HIV-infected individuals with HAND, 130 without HAND, and 150 healthy controls. Polymorphism of MMP-1 and MMP-3 were genotyped by PCR-RFLP. MMP-1-1607 2G1G, -16071G/2G-1G/1G genotypes and -1607 1G allele were associated with the development of HAND (OR = 1.64, P = 0.05; OR = 1.45, P = 0.04; OR = 1.69, P = 0.05). MMP-1-16071G1G, MMP-3-16125A5A genotypes increased the risk for the development of HAND (OR = 1.78, P = 0.25; OR = 2.39, P = 0.13). MMP-3-1612 5A5A, -1612 6A/5A-5A/5A genotypes and -1612 5A allele were associated with the reduced risk of HAND (OR = 0.40, P = 0.05; OR = 0.53, P = 0.04; OR = 0.40, P = 0.01). Haplotype 5A1G increased the risk of development of HAND (OR = 1.93, P = 0.05). As observed in advanced HIV disease stage, MMP-1-1607 1G1G genotype enhance the risk for advancement of HIV disease (OR = 1.69, P = 0.89). MMP-3-1612 6A5A genotype showed higher risk for development of HAND in alcohol users (0R = 1.65, P = 0.44). MMP-1 genotype may have an influence on development of HAND whereas MMP3-1612 5A5A genotype may reduce risk for pathogenesis of HAND. 相似文献
110.
The structural glycoprotein gene gp41 homologue of Spodoptera litura nucleopolyhedrosis virus (SpltNPV-I *) was identified in the 4.0 kb EcoRI-L fragment of the viral genome. The nucleotide sequence of 2063 bp of this fragment revealed an open reading frame of 1014 nucleotides to encode a polypeptide of 337 amino acids. Analysis of nucleotide and deduced amino acid sequences of the putative ORF indicated its identity with gp41 protein of other baculoviruses sharing maximum homology with that of Spodoptera frugiperda nucleopolyhedrosis virus (SfNPV). The coding sequence was preceded by an AT-rich region containing the consensus baculoviral late promoter motif RTAAG. The putative SpltNPV gp41 ORF was abundantly expressed as a 37 kDa apoprotein in E. coli and as a 50 kDa glycoprotein in Sf9 cells. The recombinant protein expressed in insect cells was glycosylated (20%) and has GlcNAc as the terminal sugar. The gene is conserved among baculoviruses and places SpltNPV-I close to Spodoptera frugiperda and Spodoptera exigua NPVs in phylogenetic tree.Assigned GenBank accession no. for the nucleotide sequence data is AF445192.abbreviated as SlNPV in earlier publications and GenBank 相似文献