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31.
The effect of dietary supplementation of probiotic bacterium Bacillus licheniformis on the histopathological changes in Macrobrachium rosenbergii juveniles (4.0 ± 0.02 g) challenged with known pathogenic strain of Vibrio alginolyticus are reported. Two isocaloric basal diets supplemented with probiotic bacteria B. licheniformis (1.0 × 109 cfu/g feed) and other without probiotic supplementation were fed to the M. rosenbergii juveniles for 45 days. The histological observations revealed no significant changes in the hepatopancreas and gut tissues of both the experimental and the control groups which indicate that the present bacterium is a safe candidate probiont for the host. Prawns were challenged with V. alginolyticus after 45 days of feeding with probiotic diet. The histopathological studies of the hepatopancreas revealed that M. rosenbergii fed with probiotic‐supplemented diet showed less changes as compared to the prawns fed with control diet on second and fourth day of post‐experimental challenge with V. alginolyticus. Histopathological observations revealed that the gills of the prawns fed with control diet were severely affected in comparison to the prawns fed with probiotic‐supplemented diet after challenging with V. alginolyticus. Results from this study revealed the improved protection by dietary incorporation of B. licheniformis in reducing the histopathological manifestations due to V. alginolyticus infection in freshwater prawn.  相似文献   
32.
A deoxy lupane triterpene carboxylic acid, lup-20(29)-en-24-oic acid (1), was isolated from the active chloroform extract of Finlaysonia obovata, a latex exuding mangrove plant. Its structure was evaluated on the basis of different spectroscopic methods, including extensive 1D and 2D NMR spectroscopy. Lup-20(29)-en-24-oic acid (1) has shown moderate antimicrobial activity, against some fish pathogens.  相似文献   
33.
The viability of matured oocytes stored in vitro were assessed using carp ovarian fluid (OF) and artificial carp ovarian fluid (ACOF) under different temperature regimes (4, 24, 26, 28 and 30°C) for different storage durations (0, 60, 120, 150 and 180 min). Significantly higher fertilization (74%) was achieved when the oocytes were stored using ACOF and 65% in OF after 180 min at 28°C. Similarly the hatching rates of larvae were significantly higher in the ACOF and OF, that is, 64% and 47%, respectively, after 180 min of storage. The oocytes kept in the storage containers with ACOF having 65% moisture level showed a significantly higher fertilization rate than the 59% moisture level. This study demonstrated that unfertilized matured oocytes (eggs) of rohu can be stored in vitro for 180 min without compromising the viability (fertilization and hatching) to a great extent in OF and ACOF.  相似文献   
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35.
3D woven composites provide efficient delamination suppression, enhanced damage tolerance, superior impact, ballistic and blast performance characteristics over 2D fabric laminates. At the same time, this type of composites, having practically straight in-plane fibers, show significantly better in-plane stiffness and strength properties than respective properties of conventional composites. But, how the in-plane elastic and strength characteristics of this type of fabrics compare with respective in-plane properties of equivalent 2D woven fabrics. This paper presents a comprehensive experimental study of the comparison of in-plane tensile, bending, crimp interchange properties of UD, 2D, 3D orthogonal, 3D angle-interlock and 3D warp interlock multi-layer structures woven from E-glass tow. The results depict that the 3D woven fabrics have considerably superior mechanical properties with much lesser crimp compared to 2D fabrics.  相似文献   
36.
Selection for genetically superior Murrah buffaloes under Network Project on Buffalo Improvement, India, is presently based on milk yield, and it was observed that even in the absence of any direct selection pressure applied on fertility, there has been a downward trend in fertility associated with the selection for milk yield. The aim of the study was to develop selection indices which include fertility besides milk yield in Murrah buffaloes. Data pertaining to 1,224 lactation records spread over a period of 19 years were recorded and analyzed in the study. The negative association of pregnancy rate (fertility) with a 305-day milk yield (?0.08?±?0.04) and wet average (?0.12?±?0.02) indicated the importance of incorporating fertility trait in the construction of selection index. Four types of selection indices were constructed and evaluated. Two indices were developed using expected producing ability 305-days milk yield (EPAMY) with 6.5 and 4 % fat in milk along with expected fertilizing ability (EFA). The other two indices developed consist of expected producing ability wet average (EPA WA) and EFA. The index involving (EPA WA and EFA) was found to be a more effective selection criterion in our herd, as the accuracy of index was more (0.61), in comparison to the index involving EPA MY and EFA. The robustness of selection index was assessed by increasing the relative economic values of included traits by 25 and 50 %, and accuracy of the index remains almost stable without much change. The developed selection strategy involving EPA WA and EFA should be considered for the genetic evaluation of Murrah buffaloes, as it has a potential for maximizing the lifetime reproduction and production performances of the breed.  相似文献   
37.
gammadelta T cells recognise different types of antigen in alternative ways to alphabeta T cells, and thus appear to play a complementary role in the immune response. However, unlike alphabeta T cells, the role or function of gammadelta T cells is still unclear. As pigs possess a high proportion of circulating gammadelta T cells, they are suitable large animal model to study gammadelta T cell functions. This as yet has not been fully exploited, leaving porcine gammadelta T cell biology and its role in immunity in its infancy. Foot-and-mouth disease (FMD) high potency "emergency" vaccines are able to induce early protection from challenge and it has been suggested that, in part, there is some involvement of innate immune responses. The antigen component of the vaccine is able to stimulate purified naive pig gammadelta T cells and induce the mRNA of various cytokines and chemokines. This observation suggests that gammadelta T cells probably contribute to the early phase of the immune responses to FMD vaccination, and perhaps infection. A subset of these circulating gammadelta T cells display a phenotype similar to professional antigen presenting cells and are able to take up and present soluble antigen to CD4(+) T cells in a direct cell-cell interaction via MHC class II. This direct interaction between gammadelta T cells and CD4(+) T cells is likely to have a significant influence on the out come of the adaptive immune response.  相似文献   
38.
The oral bioavailability of vasicine (1) was investigated in hard gelatin capsules of lyophilized Vasa Swaras (aqueous extract of Adhatoda vasica Nees.,Fam.: Acanthaceae) The rat pharmacokinetic profile of lyophilized Vasa Swaras, Vasa Swaras, vasicine (1) (chief marker compounds of A. vasica) and a marketed capsule formulation of A. vasica were compared. Vasicine (1) was found to be more orally bioavailable from lyophilized Vasa Swaras, with an overall minor conversion to vasicinone (2).  相似文献   
39.
Brown planthopper (BPH, Nilaparvata lugens Stål) is the most devastating pest of rice in Asia and causes significant yield loss annually. Around 37 BPH resistance genes have been identified so far in indica, African rice varieties along with wild germplasms such as Oryza officinalis, O. minuta, O. nivara, O. punctata, O. rufipogon and O. latifolia. Genes/QTLs involved in BPH resistance, including Bph1, bph2/BPH26, Bph3, Bph6, bph7, BPH9, Bph12, Bph14, Bph15, Bph17, BPH18, bph19, Bph20, Bph21(t), Bph27, Bph27(t), Bph28(t), BPH29, QBph3, QBph4, QBph4.2, Bph30, Bph32, Bph33, Bph35 and Bph36, have been fine-mapped by different researchers across the globe. The majority of genes/QTLs are located on rice chromosomes 1, 3, 4, 6, 11 and 12. Rice plants respond to BPH attack by releasing various endogenous metabolites like proteinase inhibitors, callose, secondary metabolites (terpenes, alkaloids, flavonoid, etc.) and volatile compounds. Besides that, hormonal signal pathways mediating (antagonistic/synergistic) resistance responses in rice have been well studied. Marker-assisted breeding and genome editing techniques can also be adopted for improving resistance to novel BPH biotypes.  相似文献   
40.
The present study was conducted to assess the effect of spraying of pesticides on the content of minerals in cabbage harvested at varying waiting periods (0, 7, 14 and 21 days) after spraying. The amounts of phosphorus and zinc in cabbage were significantly (p < 0.05) decreased while those of iron, calcium and potassium were significantly (p < 0.05) increased by the sprayings of pesticides. At varying waiting periods after the spraying of pesticides calcium, phosphorus, zinc and potassium contents of cabbage were found to be decreased remarkably (p < 0.05) while the content of iron was increased significantly (p < 0.05). Between the two pesticides, the spraying of endosulfan exerted a more pronounced effect in altering the contents of minerals than the spraying of malathion.  相似文献   
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