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91.
Solid-state fermentation (SSF) was performed to evaluate the potential of agricultural residues for the production of cellulase and hemicellulase using individual and mixed cultures of Aspergillus niger and Trichoderma reseei. The maximum filter paper (FP) cellulase activity of 13.57 IU/gram dry substrate (gds), 22.89 IU/gds and 24.17 IU/gds and β-glucosidase activities of 21.69 IU/gds, 13.58 IU/gds and 24.54 IU/gds were obtained with wheat bran medium at 96 h incubation period with A. niger, T. reseei and mixed-cultures of A. niger and T. reseei, respectively. Mixed-culture SSF using rice straw supplemented with wheat bran in the ratio 3:2 resulted in higher FP cellulase, β-glucosidase, endoglucanase (CMCase) and xylanase activities, compared to the activities obtained using mono-cultures. Similarly, higher FP cellulase, β-glucosidase, CMCase and xylanase activities of 35.8 IU/gds (96 h), 33.71 IU/gds (96 h), 131.34 IU/gds (120 h) and 3106.34 IU/gds (120 h) were achieved in the tray fermentation using rice straw with wheat bran in the ratio of 3:2. Results of present investigation showed that higher cellulase activity and an optimal combination of cellulase and β-glucosidase can be achieved through mixed-culture SSF in trays. The approach of utilizing negative cost agricultural wastes through tray fermentation for cellulase and hemicellulase production is expected to serve the objectives of: (a) management of wastes which would otherwise cause environmental pollution problems; (b) production of hydrolytic enzymes at low cost and; (c) simple technique requiring no sophisticated instruments with practical applications.  相似文献   
92.
The substance secreted by mussels, also known as nature’s glue, is a type of liquid protein that hardens rapidly into a solid water-resistant adhesive material. While in seawater or saline conditions, mussels can adhere to all types of surfaces, sustaining its bonds via mussel adhesive proteins (MAPs), a group of proteins containing 3,4-dihydroxyphenylalanine (DOPA) and catecholic amino acid. Several aspects of this adhesion process have inspired the development of various types of synthetic materials for biomedical applications. Further, there is an urgent need to utilize biologically inspired strategies to develop new biocompatible materials for medical applications. Consequently, many researchers have recently reported bio-inspired techniques and materials that show results similar to or better than those shown by MAPs for a range of medical applications. However, the susceptibility to oxidation of 3,4-dihydroxyphenylalanine poses major challenges with regard to the practical translation of mussel adhesion. In this review, various strategies are discussed to provide an option for DOPA/metal ion chelation and to compensate for the limitations imposed by facile 3,4-dihydroxyphenylalanine autoxidation. We discuss the anti-proliferative, anti-inflammatory, anti-microbial activity, and adhesive behaviors of mussel bio-products and mussel-inspired materials (MIMs) that make them attractive for synthetic adaptation. The development of biologically inspired adhesive interfaces, bioactive mussel products, MIMs, and arising areas of research leading to biomedical applications are considered in this review.  相似文献   
93.
Journal of Soils and Sediments - Arsenic (As) contamination of groundwater has received significant attention recently in district Bathinda, due to consequent health risk in this region. Soil is...  相似文献   
94.
Geographical variations are among the least studied factors that control or modify rooting by cuttings. In the present study 1 year old branch cuttings of 12 provenances from Central India of Azadirachta indica and Dalbergia sissoo were examined for variation in rooting ability. Application of 500 mg/l-1 indole butyric acid (IBA) significantly increased (P < 0.05) root numbers, root length, root dry weight, rooting percentage, shoot number and shoot height. The auxin treatment amplified the provenance differences in rooting ability of cuttings. No significant variation in survival was evident with respect to provenance or auxin treatment. Correlation coefficients for root parameters were positive and significant (P < 0.01) and results of principal component analysis identified rooting factor having 52.3 and 46.7% of the total sub-plot mean variance among auxin treated cuttings for A. indica and D. sissoo, respectively. On the basis of overall performance of rooting in cuttings among provenances, the Raipur provenance was adjudged the best. Opportunities to develop genetically diverse clonal production stands are discussed.  相似文献   
95.
Foliar fungal diseases(rust and late leaf spot)incur large yield losses,in addition to the deterioration of fodder quality in groundnut worldwide.High oleic acid has emerged as a key market trait in groundnut,as it increases the shelf life of the produce/products in addition to providing health benefits to consumers.Marker-assisted backcrossing(MABC)is the most successful approach to introgressing or pyramiding one or more traits using traitlinked markers.We used MABC to improve three popular Indian cultivars(GJG 9,GG 20,and GJGHPS 1)for foliar disease resistance(FDR)and high oleic acid content.A total of 22 BC3F4 and 30 BC2F4 introgression lines(ILs)for FDR and 46 BC3F4 and 41 BC2F4 ILs for high oleic acid were developed.Recurrent parent genome analysis using the 58 K Axiom_Arachis array identified several lines showing upto 94%of genome recovery among second and third backcross progenies.Phenotyping of these ILs revealed FDR scores comparable to the resistant parent,GPBD 4,and ILs with high(~80%)oleic acid in addition to high genome recovery.These ILs provide further opportunities for pyramiding FDR and high oleic acid in all three genetic backgrounds as well as for conducting multi-location yield trials for further evaluation and release for cultivation in target regions of India.  相似文献   
96.
A total of six TGMS (thermosensitive genic male sterile lines) and nine pollinator lines were subjected to molecular characterization using 48 genome-wide SSR (simple sequence repeat) markers. Cluster analysis revealed clear differentiation among the TGMS lines according to their source of origin. The SSR-based genetic distance between the hybrids of the parental lines ranged from 0.36 to 0.79 suggesting a high degree of genetic divergence. Among a set of 54 hybrids generated using parental lines, 32 showed better parent heterosis (+21.7%) while 19 showed mid-parent heterosis (+15.0%). For the trait yield per plant genetic distance (GD) was negatively correlated with F1 performance (r = ?0.202), mid-parent heterosis (r = ?0.325*; P < 0.05), and better parent heterosis (r = ?0.261), while it was positively correlated with specific combining ability (r = 0.042). Based on the grouped genetic distance (GGD), the hybrid combinations were divided into four groups. The GGD showed linear correlation with hybrid performance within the group (GGD = 40–50: r = ?0.07; GGD = 70–80: r = 0.32). This information can be utilized in the development of higher yielding, two-line rice hybrids through selection of intermediately diverse parental lines using GGD.  相似文献   
97.
The crude ethanolic extract of aerial parts of Leucas aspera was tested for its acaricidal properties against Rhipicephalus (Boophilus) annulatus. The per cent adult mortality, inhibition of fecundity and hatching of laid ova were studied at concentrations of 1.56, 3.13, 6.25, 12.5, 25, 50 and 100mg/ml. Adult tick mortality was significant at the highest concentration tested. Inhibition of fecundity of treated groups differed significantly from control and was concentration dependent. L. aspera extract also produced complete failure of eclosion of eggs from the treated ticks even at lower dilutions of the extract.  相似文献   
98.
The aim of our study was to estimate forest vulnerability and potential distribution of three bark beetles (Curculionidae: Scolytinae) under current and projected climate conditions for 2020 and 2050. Our study focused on the mountain pine beetle (Dendroctonus ponderosae), western pine beetle (Dendroctonus brevicomis), and pine engraver (Ipspini). This study was conducted across eight states in the Interior West of the US covering approximately 2.2 million km2 and encompassing about 95% of the Rocky Mountains in the contiguous US. Our analyses relied on aerial surveys of bark beetle outbreaks that occurred between 1991 and 2008. Occurrence points for each species were generated within polygons created from the aerial surveys. Current and projected climate scenarios were acquired from the WorldClim database and represented by 19 bioclimatic variables. We used Maxent modeling technique fit with occurrence points and current climate data to model potential beetle distributions and forest vulnerability. Three available climate models, each having two emission scenarios, were modeled independently and results averaged to produce two predictions for 2020 and two predictions for 2050 for each analysis. Environmental parameters defined by current climate models were then used to predict conditions under future climate scenarios, and changes in different species’ ranges were calculated. Our results suggested that the potential distribution for bark beetles under current climate conditions is extensive, which coincides with infestation trends observed in the last decade. Our results predicted that suitable habitats for the mountain pine beetle and pine engraver beetle will stabilize or decrease under future climate conditions, while habitat for the western pine beetle will continue to increase over time. The greatest increase in habitat area was for the western pine beetle, where one climate model predicted a 27% increase by 2050. In contrast, the predicted habitat of the mountain pine beetle from another climate model suggested a decrease in habitat areas as great as 46% by 2050. Generally, 2020 and 2050 models that tested the three climate scenarios independently had similar trends, though one climate scenario for the western pine beetle produced contrasting results. Ranges for all three species of bark beetles shifted considerably geographically suggesting that some host species may become more vulnerable to beetle attack in the future, while others may have a reduced risk over time.  相似文献   
99.

Present study was conducted on 12 Karan Fries (Holstein Friesian X Tharparkar) heifers (10–12 months) to assess the effect of astaxanthin supplementation on heat stress amelioration and inhibition of NF-κB signaling pathway for prevention of heat stress–induced inflammatory changes and apoptosis in the cell during the summer season. The heifers were randomly and equally divided into two groups, i.e., control (fed as per ICAR 2013) and treatment groups (additionally supplemented astaxanthin at a dose rate of 0.25 mg/kg BW/day/animal). Temperature humidity index used to assess the levels of summer stress during the experimental period. Blood samples were collected at the fortnightly interval for quantification of plasma cortisol and IL-12 from both the groups of the heifers and from collected blood samples, RNA was isolated and transcribed into cDNA for real time PCR, for genes expression of NF-κB, IL-2, caspase-3, and Bcl-2. Plasma cortisol, IL-12 levels, and expression pattern of NF-κB, IL-2, and caspase-3 were significantly (P ≤ 0.05) lower in treatment group of Karan Fries heifers than control group, whereas, Bcl-2 was higher (P ≤ 0.05) in astaxanthin supplemented group. The temperature humidity index had a positive correlation (P ≤ 0.05) with plasma cortisol and IL-12 and expression pattern of NF-κB, IL-2, and caspase-3. However, it was negatively correlated with Bcl-2. The supplementation of astaxanthin can ameliorate the impact of summer stress through NF-κB downregulation, might be due to the quenching of free radicals, which regulates the expression of pro-inflammatory mediators and apoptotic genes.

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100.
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