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61.
Tannic acid attenuates TGF‐β1‐induced epithelial‐to‐mesenchymal transition by effectively intervening TGF‐β signaling in lung epithelial cells 下载免费PDF全文
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64.
The effect of water deficit on nodulation, N2 fixation, photosynthesis, and total soluble sugars and leghemoglobin in nodules was investigated in cowpea and groundnut. Nitrogenase activity completely ceased in cowpea with a decrease in leaf water potential (
leaf) from –0.4 MPa to –0.9 MPa, while in groundnut it continued down to –1.7 MPa. With increasing water stress, the acetylene reduction activity (ARA) declined very sharply in cowpea, but ARA gradually decreased in groundnut. Even with mild water stress (
leaf of 0.2 MPa), nodule fresh weight declined 50% in cowpea partly due to a severe nodule shedding whereas nodule fresh weight declined in groundnut only when
leaf decreased by 1.0 MPa. No nodule shedding was noticed even at a higher stress level in groundnut. Photosynthesis and stomatal conductance were also more stable in groundnut than in cowpea under water stress. There was a sharp increase in total soluble sugars and leghemoglobin in the nodules of groundut with water stress, but no definite trend could be found in cowpea. 相似文献
65.
K. Rajasekaran S. C. Schank I. K. Vasil 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1986,73(1):4-10
Summary Five hundred and twenty-four plants of a triploid, sexually sterile hybrid napiergrass (Pennisetum americanum x P. purpureum; 3x=21) were regenerated from embryogenic callus cultures obtained from segments of young inflorescences. Replicated field trials were conducted for two consecutive years to compare the biomass yield, phenotype and cytology of tissue culture regenerants (TC) and vegetatively propagated (V) plants. In the first year total biomass yield of TC plants was significantly greater than V plants but there was no significant difference in the second year. TC plants had more tillers compared to V plants. V plants did not show any morphological variability. The TC population also exhibited a high degree of phenotypic stability (96%). There were 23 phenotypic variants in the TC population of 524, most of them being more dwarf and late-flowering. Detailed morphological analysis of the TC-variant plants suggests that they very likely arose from only a few variant cell lines. Cytological analysis indicated stability of the triploid status in randomly selected regenerants. Two of the morphological variants were hexaploids (6x=42). It is concluded that embryogenic callus cultures can provide useful alternative for the rapid propagation of hybrid napier-grass which is commonly propagated by cuttings. 相似文献
66.
Effect of Water Deficit on Accumulation of Dry Matter, Carbon and Nitrogen in the Kernel of Wheat Genotypes Differing in Yield Stability 总被引:2,自引:1,他引:1
Khanna-Chopra Renu; Rao P. S.S.; Maheswari M.; Xiaobing Liu; Shivshankar K. S. 《Annals of botany》1994,74(5):503-511
Water stress effects on accumulation of dry matter, carbon andnitrogen in grains were analysed in varieties and species ofwheat differing in yield stability. Variable water environmentswere generated using a line source sprinkler system. Althoughlarge fluctuations occurred in the water potentials of the flagleaf and ear, grain growth remained relatively buffered undermoisture stress. Developing grains were at a lower moisturelevel throughout grain growth in plants subjected to moisturestress relative to the unstressed plants. Carbon content decreasedmore than the nitrogen content in the stressed grains of thespecies and varieties. Reduction in the duration of grain growthand the rate of dry weight accumulation induced by water stresswas more prominent in T. aestivum var. C306 and T. sphaerococcum.Grain yield was reduced significantly under water stress, themaximum being in the high yielding cultivar HD2329. Both grainnumber and grain weight were reduced in response to stress,the extent of reduction being different in different genotypes.Copyright1994, 1999 Academic Press Water deficit, yield stability, C and N accumulation, heat degree days 相似文献
67.
K. Sreevishnupriya P. Chandrasekaran A. Senthilkumar R. Sethumadhavan V. Shanthi P. Daisy J. Nisha K. Ramanathan R. Rajasekaran 《中国科学:生命科学英文版》2012,55(12):1109-1119
In this work, the most detrimental missense mutations of aspartoacylase that cause Canavan??s disease were identified computationally and the substrate binding efficiencies of those missense mutations were analyzed. Out of 30 missense mutations, I-Mutant 2.0, SIFT and PolyPhen programs identified 22 variants that were less stable, deleterious and damaging respectively. Subsequently, modeling of these 22 variants was performed to understand the change in their conformations with respect to the native aspartoacylase by computing their root mean squared deviation (RMSD). Furthermore, the native protein and the 22 mutants were docked with the substrate NAA (N-Acetyl-Aspartic acid) to explain the substrate binding efficiencies of those detrimental missense mutations. Among the 22 mutants, the docking studies identified that 15 mutants caused lower binding affinity for NAA than the native protein. Finally, normal mode analysis determined that the loss of binding affinity of these 15 mutants was caused by altered flexibility in the amino acids that bind to NAA compared with the native protein. Thus, the present study showed that the majority of the substrate-binding amino acids in those 15 mutants displayed loss of flexibility, which could be the theoretical explanation of decreased binding affinity between the mutant aspartoacylases and NAA. 相似文献
68.
Heng B. Xie Anthony Cammarato Namakkal S. Rajasekaran Huali Zhang Jennifer A. Suggs Ho-Chen Lin Sanford I. Bernstein Ivor J. Benjamin Kent G. Golic 《PLoS genetics》2013,9(6)
Dominant mutations in the alpha-B crystallin (CryAB) gene are responsible for a number of inherited human disorders, including cardiomyopathy, skeletal muscle myopathy, and cataracts. The cellular mechanisms of disease pathology for these disorders are not well understood. Among recent advances is that the disease state can be linked to a disturbance in the oxidation/reduction environment of the cell. In a mouse model, cardiomyopathy caused by the dominant CryABR120G missense mutation was suppressed by mutation of the gene that encodes glucose 6-phosphate dehydrogenase (G6PD), one of the cell''s primary sources of reducing equivalents in the form of NADPH. Here, we report the development of a Drosophila model for cellular dysfunction caused by this CryAB mutation. With this model, we confirmed the link between G6PD and mutant CryAB pathology by finding that reduction of G6PD expression suppressed the phenotype while overexpression enhanced it. Moreover, we find that expression of mutant CryAB in the Drosophila heart impaired cardiac function and increased heart tube dimensions, similar to the effects produced in mice and humans, and that reduction of G6PD ameliorated these effects. Finally, to determine whether CryAB pathology responds generally to NADPH levels we tested mutants or RNAi-mediated knockdowns of phosphogluconate dehydrogenase (PGD), isocitrate dehydrogenase (IDH), and malic enzyme (MEN), the other major enzymatic sources of NADPH, and we found that all are capable of suppressing CryABR120G pathology, confirming the link between NADP/H metabolism and CryAB. 相似文献
69.
E Rajasekaran 《Bioinformation》2012,8(11):508-512
Carbon distribution is responsible for stability and structure of proteins. Arrangement of carbon along the protein sequence is depends on how the amino acids are organized and is guided by mRNAs. An atomic level revision is important for understanding these codes. This will ultimately help in identification of disorders and suggest mutations. For this purpose a carbon distribution analysis program has been developed. This program captures the hydrophobic / hydrophilic / disordered regions in a protein. The program gives accurate results. The calculations are precise and sensitive to single amino acid resolution. This program is to help in mutational studies leading to protein stabilisation. 相似文献
70.
Oldenlandia umbellata L., commonly known as “Indian madder”, is an ancient Indian herb valued as a source of red color dye and various medicinal
products. In this study, successful protocols have been developed for induction of somatic embryogenesis and organogenesis
in O. umbellata. Emerging young leaves, shoot apices, and stems were used as explants, grown on Murashige and Skoog (MS) media supplemented
with various auxins, including indole acetic acid, indole butyric acid, napthaleneacetic acid (NAA), and 2,4-Dichlorophenoxyacetic
acid, each at levels ranging between 0.1 and 0.5 mg/l, cytokinins, including benzyladenine (BA) and kinetin, each at concentration
ranging between 0.5 and 5 mg/l, with and without coconut milk (CM) at levels of 0.5–5%. For callus induction, NAA at 2.5 mg/l
was optimal; while, for rapid embryogenic callus induction, 0.2 mg/l NAA, 0.5 mg/l BA, and 0.1% CM induced the highest frequency
(95.86%). Shoots developed upon transfer of embryogenic calli to MS medium containing 1.5 mg/l BA, 0.3 mg/l NAA and 1% CM.
For root induction, 0.3 mg/l NAA and 1.0% CM promoted highest and earliest rooting.
C. Rajasekaran contributed equally to this work. 相似文献