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31.
A nutrient budget was quantified for six polyculture ponds of giant freshwater prawn (Macrobrachium rosenbergii) and Indian major carps (Catla catla, Labeo rohita, and Cirrhinus mrigala). The initial stocking size of prawn postlarva was 16.50 ± 0.54 mm with a body weight of 0.05 ± 0.001 g. Body weight of major carps was 9.0 ± 0.89 g. The duration of culture was 280 days. Feed accounted for 82% of total nitrogen (N), 93% of total phosphorus (P), and 95% of organic carbon (OC) inputs. Harvest of prawn and carps recovered 44% N, 1% P, and 19% OC. N, P, and OC accumulated in sediment were 47%, 73%, and 69%, respectively. Nutrient load in the harvest water was 0.67 ± 0.21 kg inorganic N, 0.15 ± 0.01 kg P, and 7.72 ± 0.62 kg OC per ton of Indian major carps and prawn.  相似文献   
32.
BACKGROUND: Farmers are faced with a wide range of pest management (PM) options that can be adopted in isolation or alongside complementary or substitute strategies. This paper presents the results of a survey of UK cereal producers, focusing on the character and diversity of PM strategies currently used by, or available to, farmers. In addition, the survey asked various questions pertaining to agricultural policy participation, attitude towards environmental issues, sources of PM advice and information and the important characteristics of PM technologies. RESULTS: The results indicate that many farmers do make use of a suite of PM techniques, and that their choice of integrated PM (IPM) portfolio appears to be jointly dictated by farm characteristics and government policy. Results also indicate that portfolio choice does affect the number of subsequent insecticide applications per crop. CONCLUSIONS: These results help to identify the type of IPM portfolios considered to be adoptable by farmers and highlight the importance of substitution in IPM portfolios. As such, these results will help to direct R&D effort towards the realisation of more sustainable PM approaches and aid the identification of potential portfolio adopters. These findings highlight the opportunity that a revised agri‐environmental policy design could generate in terms of enhancing coherent IPM portfolio adoption. Copyright © 2009 Society of Chemical Industry  相似文献   
33.
Knowledge of spatial variation of soil is important in site-specific farming and environmental modeling. Soil particles size and water distribution are most important soil physical properties that governing nearly all of the other attributes of soils. The objectives of this study were to determine the degree of spatial variability of sand, silt and clay contents, and water content at field capacity (FC), permanent wilting point (PWP), and available water content (AWC) of alluvial floodplain soils. Data were analyzed both statistically and geostatistically to describe the spatial distribution of soil physical properties. Soil physical properties showed large variability with greatest variation was observed in sand content (68%). Exponential and spherical models were fit well for the soil physical properties. The nugget/sill ratio indicates except clay all other soil physical properties were moderate spatially dependent (37–70%). Cross-validation of the kriged map shows that prediction of the soil physical properties using semivariogram parameters is better than assuming mean of observed value for any unsampled location. The spatial distribution of water retention properties closely followed the distribution pattern of sand and clay contents. These maps will help to planner to develop the variable rate of irrigation (VRI) for the study area.  相似文献   
34.
Investigations have been carried out to determine the influence of chlorocholine chloride on induction of the resistance mechanisms of Stevia rebaudiana against leaf spot disease, caused by Alternaria alternata. The paper also focuses an impact of chlorocholine chloride induced resistance on reduction of leaf spot disease. Chlorocholine chloride is attributed to its significant role in defence responses through augmentation of phenol and salicylic acid content as well as stimulation of phenylalanine ammonia lyase and peroxidase activity in S. rebaudiana following inoculation with A. alternata. Histochemical studies revealed that fungal invasion as well as infection process was appreciably reduced in chlorocholine chloride treated plants through peroxidase-H2O2 mediated strengthening of cell wall. The overall study highlights the significant role of chlorocholine chloride in induction of resistance in S. rebaudiana against A. alternata.  相似文献   
35.
Non-renewable nature of rock phosphate (RP) reserves coupled with open ended nature of P cycle makes it imperative for maximum utilization of available P resources. In this context, use of Indian RPs from Purulia and Udaipur along with citric acid loaded nanoclay polymer composite (CA-NCPC) as P source to costly diammonium phosphate (DAP) was investigated through an incubation experiment followed by a greenhouse experiment with wheat-rice cropping sequence in a Luvisol (pH 5.14, available P 13.5 mg kg?1). Soil available P, crop yield parameters and dynamics of soil P fractions were taken to judge the efficacy of CA-NCPC in solubilizing RPs. Application of CA-NCPC and DAP resulted in 82% and 69% increase in available P over control, respectively under incubation study. Direct effect of treatment receiving CA-NCPC + RP on yield and P uptake by wheat was comparable with DAP but residual impact of CA-NCPC + RP (16.7 g pot?1) was better than DAP (13.8 g pot?1) in rice. The changes in inorganic P fractions were also significant as inclusion of RP increased calcium-P from 16.1 to 61.5 mg kg?1. Results indicated potentiality of RPs treated with CA-NCPC as an alternate P source which could prove promising amidst P scarcity.  相似文献   
36.
Aesthetic properties of fabrics have been considered as the most important fabric attribute for years. However, recently there has been a paradigm shift in the domain of textile material applications and consequently more emphasis is now being given on the mechanical and functional properties of fabrics rather than its aesthetic appeal. Moreover, in certain woven fabrics used for technical applications, strength is a decisive quality parameter. In this work, tensile strength of plain woven fabrics has been predicted by using two empirical modelling methods namely artificial neural network (ANN) and linear regression. Warp yarn strength, warp yarn elongation, ends per inch (EPI), picks per inch (PPI) and weft count (Ne) were used as input parameters. Both the models were able to predict the fabric strength with reasonably good precision although ANN model demonstrated higher prediction accuracy and generalization ability than the regression model. The warp yarn strength and EPI were found to be the two most significant factors influencing fabric strength in warp direction.  相似文献   
37.
Proteasome-independent functions of ubiquitin in endocytosis and signaling   总被引:2,自引:0,他引:2  
Ubiquitination is a reversible posttranslational modification of cellular proteins, in which a 76-amino acid polypeptide, ubiquitin, is primarily attached to the epsilon-amino group of lysines in target proteins. Ubiquitination is a major player in regulating a broad host of cellular processes, including cell division, differentiation, signal transduction, protein trafficking, and quality control. Aberrations in the ubiquitination system are implicated in pathogenesis of some diseases, certain malignancies, neurodegenerative disorders, and pathologies of the inflammatory immune response. Here, we discuss the proteasome-independent roles of ubiquitination in signaling and endocytosis.  相似文献   
38.
Adipose tissue-derived stromal vascular fraction (AdSVF) comprises a heterogeneous cell population, including the multipotent mesenchymal stem cells, hematopoietic stem cells, immune cells, endothelial cells, fibroblasts, and pericytes. As such, multipotent adipose tissue-derived mesenchymal stem cells (AdMSCs), are one of the important components of AdSVF. Commonly used techniques to harvest AdSVF involve enzymatic or non-enzymatic methods. The enzymatic method is considered to be the gold standard technique due to its higher yield. The cellular components of AdSVF can be resuspended in normal saline, platelet-rich plasma, or phosphate-buffered saline to produce a ready-to-use solution. Freshly isolated AdSVF has exhibited promising osteogenic and vasculogenic capacity. AdSVF has already been proven to possess therapeutic potential for osteoarthritis management. It is also an attractive therapeutic option for enhancing wound healing. In addition, the combined use of AdSVF and platelet-rich plasma has an additive stimulatory effect in accelerating wound healing and can be considered an alternative to AdMSC treatment. It is also widely used for managing various orthopaedic conditions in clinical settings and has the potential for regenerating bone, cartilage, and tendons. Autologous AdSVF cells are used along with bone substitutes and other biological factors as an alternative to conventional bone grafting techniques owing to their promising osteogenic and vasculogenic capacity. It can also be used for treating osteonecrosis, meniscus tear, chondromalacia, and tendon injuries in veterinary practice. It has several advantages over in vitro expanded AdMSC, including precluding the need for culturing, reduced risk of cell contamination, and cost-effectiveness, making it ideal for clinical use.  相似文献   
39.
BackgroundA systemic and dysregulated immune response to infection contributes to morbidity and mortality associated with sepsis. Peripheral blood‐derived mesenchymal stromal cells (PB‐MSC) mitigate inflammation in animal models of sepsis. Allogeneic PB‐MSC administered IV to horses is well‐tolerated but therapeutic benefits are unknown.HypothesisAfter IV lipopolysaccharide (LPS) infusion, horses treated with PB‐MSC would have less severe clinical signs, clinicopathological abnormalities, inflammatory cytokine gene expression, and oxidative stress compared to controls administered a placebo.AnimalsSixteen horses were included in this study.MethodsA randomized placebo‐controlled experimental trial was performed. Sixteen healthy horses were assigned to 1 of 2 treatment groups (1 × 109 PB‐MSC or saline placebo). Treatments were administered 30 minutes after completion of LPS infusion of approximately 30 ng/kg. Clinical signs, clinicopathological variables, inflammatory cytokine gene expression, and oxidative stress markers were assessed at various time points over a 24‐hour period.ResultsA predictable response to IV LPS infusion was observed in all horses. At the dose administered, there was no significant effect of PB‐MSC on clinical signs, clinicopathological variables, or inflammatory cytokine gene expression at any time point. Antioxidant potential was not different between treatment groups, but intracellular ROS increased over time in the placebo group. Other variables that changed over time were likely due to effects of IV LPS infusion.Conclusions and Clinical ImportanceAdministration of allogeneic PB‐MSC did not cause clinically detectable adverse effects in healthy horses. The dose of PB‐MSC used here is unlikely to exert a beneficial effect in endotoxemic horses.  相似文献   
40.
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