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Isolation and characterization of fluorescent pseudomonads with high phosphate-solubilizing ability is reported from the alkaline and calcium-rich soils with low P availability in the cold desert region of Lahaul and Spiti in the trans-Himalayas of India. Of 216 phosphate-solubilizing isolates, 12 exhibiting high solubilization of tricalcium phosphate (TCP) in NBRIP liquid culture were identified as Pseudomonas trivialis, P. poae, P. fluorescens, and Pseudomonas spp. on the basis of phenotypic features, whole-cell fatty acids methyl ester (FAME) profiles, and 16S rDNA sequencing. These isolates also showed relatively high solubilization of North Carolina rock phosphate (NCRP) in comparison to the solubilization of Mussoorie rock phosphate (MRP) and Udaipur rock phosphate (URP). The solubilization of phosphate substrates by P. trivialis and P. poae is reported for the first time.  相似文献   
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A protocol for large-scale propagation of Piper betle cvs Desawari and Desi Bangla was developed through axillary shoot proliferation. Due to systemic infection as well as high phenol content the crop was very difficult to establish in aseptic condition. But a mixture of 5 mg l?1 each of chloramphenicol and oxytetracyclin and 100 mg l?1 each of citric acid and ascorbic acid used in MS medium for 2 days helped in establishment. After 48 h, the explants were transferred to the antibiotic free medium having PVP and ascorbic acid (100 mg l?1 each), citric acid (50 mg l?1), and glutathione (20 mg l?1). Regular subculturing of the explants into liquid medium, use of antioxidants and incubation of the cultures in the dark for initial 7–10 days played a crucial role for keeping them fresh and green. Maximum numbers of axillary shoots were obtained with 2 mg l?1 BA and 0.2 mg l?1 NAA as growth supplements. The plants were rooted in 0.25 mg l?1 IBA and hardened in the soil. Phenolic compound analysis showed almost the same results in tissue-raised and in vivo grown plants in Desawari.  相似文献   
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Plasmonics - In this paper, focus is on the light trapping surface in crystalline silicon (c-Si) solar cells where thinner c-Si wafers are expected to be used by industry to reduce the cost of cell...  相似文献   
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Alpha-linolenic acid (ALA) deficiency and a skewed n6:n3 fatty acid ratio in the diet is a major explanation for the prevalence of cardiovascular diseases and inflammatory/autoimmune diseases. There is mounting evidence of the health benefits associated with omega-3 long chain polyunsaturated fatty acids (LC PUFA’s). Although present in abundance in fish, a number of factors limit our consumption of fish based omega-3 PUFA’s. To name a few, overexploitation of wild fish stocks has reduced their sustainability due to increased demand of aquaculture for fish oil and meal; the pollution of marine food webs has raised concerns over the ingestion of toxic substances such as heavy metals and dioxins; vegetarians do not consider fish-based sources for supplemental nutrition. Thus alternative sources are being sought and one approach to the sustainable supply of LC-PUFAs is the metabolic engineering of transgenic plants with the capacity to synthesize n3 LC-PUFAs. The present investigation was carried out with the goal of developing transgenic safflower capable of producing pharmaceutically important alpha-linolenic acid (ALA, C18:3, n3). This crop was selected as the seeds accumulate ~?78% of the total fatty acids as linoleic acid (LA, C18:2, n6), the immediate precursor of ALA. In the present work, ALA production was achieved successfully in safflower seeds by transforming safflower hypocotyls with Arabidopsis specific delta 15 desaturase (FAD3) driven by truncated seed specific promoter. Transgenic safflower fortified with ALA is not only potentially valuable nutritional superior novel oil but also has reduced ratio of LA to ALA which is required for good health.  相似文献   
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In Withania somnifera, sterol molecules of immense medicinal value are diversified by means of glycosylation. Identifying sterol glycosyltransferases provides an imperative insight of diverse sterol modifications, thereby helping to comprehend the underlying plant mechanisms. In the present study, one of the W. somnifera sterol glycosyltransferase-4 (Ws-Sgtl4) gene was transformed into the W. somnifera leaf explant through Agrobacterium rhizogene. Transformed W. Somnifera Ws-Sgtl4 leaf explants were subjected to hairy root induction and analyzed for biomass accumulation. The analysis of Ws-Sgtl4 gene expression was performed at different time exposures with the application of salicylic acid and methyl jasmonate. The elicitation of W. somnifera hairy root expressing the Ws-Sgtl4 gene was also evaluated for the enhancement if any, in the total withanolide yield as well as the withanolides-A contents. The results suggested that Ws-Sgtl4 gene expression enhanced the production of total withanolide yield and withanolides-A in the hairy root culture of W. somnifera in the response to the elicitors.  相似文献   
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Salt stress has multiple damaging effects on plants including physiological damage, reduced growth, and productivity. Plant growth-promoting rhizobacteria (PGPR) are one of the valuable options to mitigate the negative effects of this stress. In the present study, native bacteria from chickpea’s rhizosphere were isolated, and checked for their salt tolerance and plant growth-promoting attributes (phosphate (P) solubilization, siderophores, indole-3-acetic acid (IAA) production, and 1-aminocyclopropane-1-carboxylate (ACC) deaminase production). One isolate, subsequently identified as Pantoea dispersa, showed appreciable production of IAA (218.3 µg/ml) and siderophores (60.33% SU), P-solubilization (3.64 µg/ml) and ACC deaminase activity (207.45 nmol/mg/h) in the presence of 150 mM NaCl, under laboratory conditions. Salt stress in uninoculated chickpea (GPF2 cultivar) plants induced high accumulation of Na+ ions (3.86 mg g?1 dw) in the leaves, along with significant reduction in K+ uptake, membrane integrity, chlorophyll concentration, and leaf water content, thus resulting in impaired growth of the plant and yield (pods and seeds) in a salt concentration-dependent manner. The damage due to salt stress was restored significantly in plants inoculated with P. dispersa. A significant improvement in biomass (32–34%), pods number (31–34.5%), seeds number (32–35.7%), pods weight (30–32.6%), and seeds weight (27–35%) per plant occurred in salt stress-affected plants, which was associated with significant reduction in Na+ uptake, reduced membrane damage, significantly improved leaf water content, chlorophyll content, and K+ uptake. This study suggests for the first time that native P. dispersa strain PSB3 can be used to alleviate the negative effects of salt stress on chickpea plants and holds the potential to be used as a biofertilizer.  相似文献   
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