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81.
In this study, 5 μmol·L-1 abscisic acid (ABA) and gibberellic acid (GA3) were used to study the effect of both growth regulators on the morphological parameters and pigment composition of Andrographispaniculata. The growth regulators were applied by means of foliar spray during morning hours. ABA treatment inhibited the growth of the stem and internodal length when compared with control, whereas GA3 treatment increased the plant height and internodal length. The total number of leaves per plant decreased in the ABA-treated plants, but GA3 treatment increased the total number of leaves when compared with the control. Both growth regulators (ABA and GA3) showed increased leaf area. ABA and GA3 treatments slightly decreased the total root growth at all the stages of growth. The growth regulator treatments increased the whole plant fresh and dry weight at all stages of growth. ABA enhanced the fresh and dry weight to a larger extent when compared with GA3. An increase in the total chlorophyll content was recorded in ABA and GA3 treatments. The chlorophyll-a, chlorophyll-b, and carote-noids were increased by ABA and GA3 treatments when compared with the control plants. The xanthophylls and anthocyanin content were increased with ABA and GA3 treatments in A. Paniculata plants.  相似文献   
82.
继代周期和接种量对葡萄细胞培养的影响   总被引:3,自引:1,他引:2  
在每种不同的继代周期和接种量条件下,葡萄细胞在连续10次继代培养过程中的生物量、花青素含量、胞内糖、胞内蛋白及胞内总磷均表现出不同程度的波动。不同接种量对培养不稳定性的影响比不同继代周期大;在所考察的条件中,7d继代周期与1.60g接种量组合的继代条件下花青素合成相对稳定;花青素合成与胞内蔗糖或胞内总磷水平呈负相关。  相似文献   
83.
目的:探讨来自心里美萝卜、紫甘薯和紫玉米的3种不同的花色苷对DF-1细胞单层生长的影响。方法:直观观察3种花色苷对DF-1细胞生长的影响,初步摸索其最适终浓度;用MTT法检测花色苷在提高细胞活性方面的作用。结果:不同浓度的3种花色苷均对细胞单层生长有不同的影响,心里美萝卜花色苷、紫甘薯花色苷和紫玉米花色苷对细胞生长的最适终浓度分别为100、75和50μg/mL;用MTT法获得相应数据并制成细胞活性图表。结论:不同品种来源及不同浓度的花色苷对DF-1细胞单层生长均有明显影响,为今后开展花色苷促细胞生长,提高细胞抗病毒活性研究提供了数据基础。  相似文献   
84.
紫黑米种质功能成分综合研究与利用   总被引:2,自引:0,他引:2  
紫黑米富含花青素、黄酮、多酚等功能成分,着重介绍了花青素等功能成分的含量差异及其影响因素、功能研究、基于代谢机理与育种及食品加工工艺的功能成分强化研究、功能成分的利用及提取工艺等领域的研究进展。针对国内外紫黑米功能成分综合研究利用进展,提出紫黑米的育种利用、食品保健、医药研发和分子机理研究及其新型功能食品研制与产业化对策,以期为紫黑米相关研究提供参考。  相似文献   
85.
The Arabidopsis transparent testa (tt) mutant tt19-4 shows reduced seed coat colour, but stains darkly with DMACA and accumulates anthocyanins in aerial tissues. Positional cloning showed that tt19-4 was allelic to tt19-1 and has a G-to-T mutation in a conserved 3'-domain in the TT19-4 gene. Soluble and unextractable seed proanthocyanidins and hydrolysis of unextractable proanthocyanidin differ between wild-type Col-4 and both mutants. However, seed quercetins, unextractable proanthocyanidin hydrolysis, and seedling anthocyanin content, and flavonoid gene expression differ between tt19-1 and tt19-4. Transformation of tt19-1 with a TT19-4 cDNA results in vegetative anthocyanins, whereas TT19-4 cDNA cannot complement the proanthocyanidin and pale seed coat phenotype of tt19-1. Both recombinant TT19 and TT19-4 enzymes are functional GSTs and are localized in the cytosol, but TT19 did not function with wide range of flavonoids and natural products to produce conjugation products. We suggest that the dark seed coat of Arabidopsis is related to soluble proanthocyanidin content and that quercetin holds the key to the function of TT19. In addition, TT19 appears to have a 5' GSH-binding domain influencing both anthocyanin and proanthocyanidin accumulation and a 3' domain affecting proanthocyanidin accumulation by a single amino acid substitution.  相似文献   
86.
Young organisms have relatively strong resistance to diseases and adverse conditions. When confronted with adversity, the process of development is delayed in plants. This phenomenon is thought to result from the rebalancing of energy, which helps plants to coordinate the relationship between development and stress tolerance; however, the molecular mechanism underlying this phenomenon remains mysterious. In this study, we found that miR156 integrates environmental signals to ensure timely flowering, thus enabling the completion of breeding. Under stress conditions, miR156 is induced to maintain the plant in the juvenile state for a relatively long period of time, whereas under favorable conditions, miR156 is suppressed to accelerate the developmental transition. Blocking the miR156 signaling pathway in Arabidopsis thaliana with 35S::MIM156 (via target mimicry) increased the sensitivity of the plant to stress treatment, whereas overexpression of miR156 increased stress tolerance. In fact, this mechanism is also conserved in Oryza sativa (rice). We also identified downstream genes of miR156, i.e. SQUAMOSA PROMOTER BINDING PROTEINLIKE 9 (SPL9) and DIHYDROFLAVONOL‐4‐REDUCTASE (DFR), which take part in this process by influencing the metabolism of anthocyanin. Our results uncover a molecular mechanism for plant adaptation to the environment through the miR156‐SPLs‐DFR pathway, which coordinates development and abiotic stress tolerance.  相似文献   
87.
Corrigendum     
正Li W,Wang B,Wang M,Chen M,Yin JM,Kaleri GM,Zhang RJ,Zuo TN,You X and Yang Q(2014)Cloning and characterization of a potato StAN11gene involved in anthocyanin biosynthesis regulation.J Integr Plant Biol 56(4):364–372.DOI:10.1111/jipb.12136The authors would like to draw the reader’s attention to an error in the following article:  相似文献   
88.
The activity of 3-deoxy-D-arabino-heptulosonate 7-phosphate (DAHP) synthase (DS-Mn, DS-Co), phenylalanine ammonia-lyase (PAL), and chalcone synthase (CHS) was monitored at various light intensities (dark, 8.88 μmol m−2 s−1, 88.8 μmol m−2 s−1) using a strawberry cell suspension culture. DS-Mn, PAL, and CHS were found to increase significantly (p>0.05) under light intensitie of 88.8 μmol m−2 s−1 compared to those of 8.88 μmol m−2 s−1 and dark. The activity of DS-Mn, PAL, and CHS were maximum at 88.8 μmol m−2 s−1. Anthocyanin content reached a maximum after 48–60 h of culturing at 88.8 μmol m−2 s−1. DS-Co showed greater activity than DS-Mn during cell culturing, but showed no correlation with anthocyanin production and light intensity. The CHS gene expression was continuous at a light intensity of 88.8 μmol m−2 s−1. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
89.
A thermophilic acidophilic bacterium was isolated from Owaku-dani hot springs of Izu-Hakone National Park in Japan. This bacterium grows optimally at a temperature of 70°C and a pH of 2~3. The isolate was generally spherical in shape, with a diameter of about 0.8~1.2 μm, being gram-negative and nonmotile. The DNA base composition was 44% guanine plus cytosine. Chromatographic, chemical and infrared spectroscopic analysis of the total cellular lipid showed that the lipid constituents contained mainly ether linkages; long chain fatty acids and derivatives were absent. The data presented suggests that the thermophilic acidophilic isolate may have some relationship to the Sulfolobus.  相似文献   
90.
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