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Developing fragrant rice through marker‐assisted/aided selection (MAS) is an economical and profitable approach worldwide for the enrichment of an elite genetic background with a pleasant aroma. The PCR‐based DNA markers that distinguish the alleles of major fragrance genes in rice have been synthesised to develop rice scent biofortification through MAS. Thus, the present study examined the aroma biofortification potential of these co‐dominant markers in a germplasm panel of 189 F2 progeny developed from crosses between a non‐aromatic variety (MR84) and a highly aromatic but low‐yielding variety (MRQ74) to determine the most influential diagnostic markers for fragrance biofortification. The SSRs and functional DNA markers RM5633 (on chromosome 4), RM515, RM223, L06, NKSbad2, FMbadh2‐E7, BADEX7‐5, Aro7 and SCU015RM (on chromosome 8) were highly associated with the 2AP (2‐acetyl‐1‐pyrroline) content across the population. The alleles traced via these markers were also in high linkage disequilibrium (R2 > 0.70) and explained approximately 12.1, 27.05, 27.05, 27.05, 25.42, 25.42, 20.53, 20.43 and 20.18% of the total phenotypic variation observed for these biomarkers, respectively. F2 plants harbouring the favourable alleles of these effective markers produced higher levels of fragrance. Hence, these rice plants can be used as donor parents to increase the development of fragrance‐biofortified tropical rice varieties adapted to growing conditions and consumer preferences, thus contributing to the global rice market.  相似文献   
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Valve interstitial cells (VICs) are fibroblastic in nature however in culture it is widely accepted that they differentiate into a myofibroblastic phenotype. This study assessed a fibroblast culture media formulation for its ability to maintain the phenotype and function of VICs as in the intact healthy valve. Normal human VICs were cultured separately in standard DMEM and in fibroblast media consisting of FGF2 (10ng/ml), insulin (50ng/ml) and 2% FCS for at least a week. Cell morphology, aspect ratio, size, levels and distribution of protein expression, proliferation, cell cycle, contraction and migration were assessed. Some VICs and some valve endothelial cells expressed FGF2 in valve tissue and this expression was increased in calcified valves. VICs in DMEM exhibited large, spread cells whereas VICs in fibroblast media were smaller, elongated and spindly. Aspect ratio and size were both significantly higher in DMEM (p<0.01). The level of expression of α-SMA was significantly reduced in fibroblast media at day 2 after isolation (p<0.01) and the expression of α-SMA, SM22 and EDA-fibronectin was significantly reduced in fibroblast media at days 7 and 12 post-isolation (p<0.01). Expression of cytoskeletal proteins, bone marker proteins and extracellular matrix proteins was reduced in fibroblast media. Proliferation of VICs in fibroblast media was significantly reduced at weeks 1 (p<0.05) and 2 (p<0.01). Collagen gel contraction was significantly reduced in fibroblast media (p<0.05). VICs were found to have significantly fewer and smaller focal adhesions in fibroblast media (p<0.01) with significantly fewer supermature focal adhesions in fibroblast media (p<0.001). Ultrastructurally, VICs in fibroblast media resembled native VICs from intact valves. VICs in fibroblast media demonstrated a slower migratory ability after wounding at 72 hours (p<0.01). Treatment of human VICs with this fibroblast media formulation has the ability to maintain and to dedifferentiate the VICs back to a fibroblastic phenotype with phenotypic and functional characteristics ascribed to cells in the intact valve. This methodology is fundamental in the study of normal valve biology, pathology and in the field of tissue engineering.  相似文献   
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Evidence suggests that the plasma membrane Ca2+-ATPase (PMCA), which is critical for maintaining a low intracellular Ca2+ concentration ([Ca2+]i), utilizes glycolytically derived ATP in pancreatic ductal adenocarcinoma (PDAC) and that inhibition of glycolysis in PDAC cell lines results in ATP depletion, PMCA inhibition, and an irreversible [Ca2+]i overload. We explored whether this is a specific weakness of highly glycolytic PDAC by shifting PDAC cell (MIA PaCa-2 and PANC-1) metabolism from a highly glycolytic phenotype toward mitochondrial metabolism and assessing the effects of mitochondrial versus glycolytic inhibitors on ATP depletion, PMCA inhibition, and [Ca2+]i overload. The highly glycolytic phenotype of these cells was first reversed by depriving MIA PaCa-2 and PANC-1 cells of glucose and supplementing with α-ketoisocaproate or galactose. These culture conditions resulted in a significant decrease in both glycolytic flux and proliferation rate, and conferred resistance to ATP depletion by glycolytic inhibition while sensitizing cells to mitochondrial inhibition. Moreover, in direct contrast to cells exhibiting a high glycolytic rate, glycolytic inhibition had no effect on PMCA activity and resting [Ca2+]i in α-ketoisocaproate- and galactose-cultured cells, suggesting that the glycolytic dependence of the PMCA is a specific vulnerability of PDAC cells exhibiting the Warburg phenotype.  相似文献   
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The beneficial effects of endophytes on plant growth are important for agricultural ecosystems because they reduce the need for fertilizers and decrease soil and water pollution while compensating for environmental perturbations. Endophytic fungi are a novel source of bioactive secondary metabolites; moreover, recently they have been found to produce physiologically active gibberellins as well. The symbiosis of gibberellins producing endophytic fungi with crops can be a promising strategy to overcome the adverse effects of abiotic stresses. The association of such endophytes has not only increased plant biomass but also ameliorated plant-growth during extreme environmental conditions. Endophytic fungi represent a trove of unexplored biodiversity and a frequently overlooked component of crop ecology. The present review describes the role of gibberellins producing endophytic fungi, suggests putative mechanisms involved in plant endophyte stress interactions and discusses future prospects in this field.  相似文献   
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Experiments were conducted to investigate the role of a newly isolated endophytic fungus GMC-2A on physiology of host plant (Glycine max. L cv. Hwangkeum-kong) growing under salinity stress. GMC-2A was identified as a new strain of Penicillium funiculosum on the basis of sequence homology and phylogenetic analysis of D1/D2 regions of 28S rDNA. Preliminary screening experiment showed that the culture filtrate (CF) of GMC-2A promoted the growth of Waito-C, a dwarf gibberellin (GA) biosynthesis mutant rice cultivar. Analysis of fungal CF revealed the presence of GAs (GA1 1.53 ng/ml; GA4 9.34 ng/ml; GA8 1.21 ng/ml; GA9 37.87 ng/ml) and indole acetic acid (14.85 μg/ml). GMC-2A also showed high phosphate solubilization of tricalcium phosphate. Besides that, GMC-2A application enhanced soybean seed germination as compared to control. Under salinity stress (70 and 140 mM), GMC-2A significantly promoted the soybean growth attributes (shoot length, shoot fresh/dry biomass, chlorophyll content, photosynthesis rate and leaf area) in comparison to control treatments. We also observed low endogenous abscisic acid and elevated jasmonic acid contents in GMC-2A treated plants under salt stress. GMC-2A treatment significantly enhanced levels of isoflavones (34.22% and 75.37%) under salinity stress as compared to control. In conclusion, P. funiculosum LHL06 has significantly ameliorated the adverse effects of salinity induced abiotic stress, and re-programmed soybean to higher growth and isoflavone biosynthesis.  相似文献   
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Salient sensory environments experienced by a parental generation can exert intergenerational influences on offspring. While these data provide an exciting new perspective on biological inheritance, questions remain about causes and consequences of intergenerational influences of salient sensory experience. We previously showed that exposing male mice to a salient olfactory experience, like olfactory fear conditioning, resulted in offspring demonstrating a sensitivity to the odor used to condition the paternal generation and possessing enhanced neuroanatomical representation for that odor. In this study, we first injected RNA extracted from sperm of male mice that underwent olfactory fear conditioning into naïve single‐cell zygotes and found that adults that developed from these embryos had increased sensitivity and enhanced neuroanatomical representation for the odor (Odor A) with which the paternal male had been conditioned. Next, we found that female, but not male offspring sired by males conditioned with Odor A show enhanced consolidation of a weak single‐trial Odor A + shock fear conditioning protocol. Our data provide evidence that RNA found in the paternal germline after exposure to salient sensory experiences can contribute to intergenerational influences of such experiences, and that such intergenerational influences confer an element of adaptation to the offspring. In so doing, our study of intergenerational influences of parental sensory experience adds to existing literature on intergenerational influences of parental exposures to stress and dietary manipulations and suggests that some causes (sperm RNA) and consequences (behavioral flexibility) of intergenerational influences of parental experiences may be conserved across a variety of parental experiences.  相似文献   
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