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101.
Using easily measurable soil properties could save time and cost for field capacity (FC) prediction. The objective of this study was to compare Mamdani fuzzy inference system (MFIS) and regression tree (RT) for FC predicting using such properties. One hundred and sixty-five soil samples from Unsaturated Soil hydraulic database data-set and 45 from Hydraulic Properties of European Soils data-set were used for the development and validation of MFIS and RT, respectively. Fuzzy rules and tree diagram based on the relationships between these predictor variables and the response variable FC were defined and 48 rules were written. Results showed a positive linear relevancy in terms of standardized independent variable weight, W*, between clay content and FC and negative linear relevancy between geometric mean particular size diameter (dg) and FC. Among predictor variables, dg (W* = 0.81) and bulk density (BD) (W* = 0.49) had the highest and lowest influence on FC, respectively. A tree diagram is presented for the prediction of FC using clay content, dg, and BD. Overall, based on statistical parameters, RT method (R2 = 0.78, geometric mean error (GME) = 1.02, mean error (ME) = 0.01 cm3 cm?3, and root mean square error (RMSE) = 0.04 cm3 cm?3) showed a higher performance than MFIS method (R2 = 0.72, GME = 1.16, ME = 0.08 cm3 cm?3, and RMSE = 0.06 cm3 cm?3) to predict FC.  相似文献   
102.
During the last few years, numerous attempts were made to identify effective α-glucosidase inhibitors from natural sources in order to develop new alternatives for diabetes management. Smallanthus sonchifolius (yacon) leaves were found to be effective in controlling postprandial hyperglycemia. Enhydrin, a constituent of yacon leaves, was noted for its significant hypoglycemic properties in diabetic rats. These properties were also demonstrated for yacon leaves decoction, which is rich in phenolic compounds such as chlorogenic acid and its derivatives. The purpose of the present study was to evaluate the potential of yacon leaves decoction and the isolated compound enhydrin to inhibit α-glucosidase enzyme, a possible mechanism of the above antihyperglycemic effect. In vitro assays showed that both 10% decoction and enhydrin significantly inhibited the activity of the yeast α-glucosidase enzyme in a dose-dependent manner, IC50 values being 50.40 and 134.17 μg/ml, respectively. In vivo experiments showed a rapid decrease in the hyperglycemic peak after sucrose load (2 g/kg body weight) in normal rats treated with the 10% decoction (140 mg/kg) and enhydrin (0.8 mg/kg). Both treatments caused a significant decrease in blood glucose levels in diabetic rats after sucrose load compared to diabetic control. These results suggest that both products assayed could be effective in the management of postprandial hyperglycemia through inhibition of α-glucosidase in the small intestine.  相似文献   
103.
Because of concerns regarding health, safety, and aesthetics, a test that identifies the presence of sewage sludge or its products (biosolids) in commercial materials such as soil conditioners and composts would be useful. This test could also trace the effluent plume from a sewage treatment plant. We have discovered that synthetic fibers serve as such an indicator. Synthetic fibers are abundant in sludge, sludge products, and sewage treatment plant effluents. The fibers evidently are introduced from clothes-washing machines and survive the sewage treatment process. Synthetic fibers were identified using polarized light microscopy, which provided a simple, rapid method for determining the presence or absence of municipal sewage sludge or its products. False positives or false negatives have not occurred with any of the materials examined so far. We also monitored synthetic fibers in surface sediments of Huntington Harbor, Long Island, NY, a harbor receiving the effluent from a trickling filter sewage treatment plant. Fibers generally decrease in size and abundance with distance from the source. In Oyster Bay Harbor, Long Island, an advanced sewage treatment plant is operated with a final microfiltration step. Synthetic fibers are less abundant in the sediments of this harbor.  相似文献   
104.

This study aimed to investigate the milk production potential and the impact of nongenetic factors on milk yield and composition of Tunisian dromedary camels. Milk recording and sampling were carried out at monthly intervals over complete lactation for 3 years from 95 camels reared in intensive and semi-intensive systems. The overall means of daily milk yield and fat, protein, total solids, and ash contents were 4.21 ± 1.98 l/day, 2.45 ± 0.9%, 2.67 ± 0.74%, 10.75 ± 1.41%, and 0.85 ± 0.08%, respectively. The total milk yield was 1388.41 ± 575.46 l/lactation for 11 months of lactation. The daily milk yield increased regularly throughout lactation until it reached its peak in the 4th month postpartum and then decreased until the 17th month postpartum. The chemical components, except ash, followed an opposite trend to the milk yield. Their minimum contents were recorded during the 7th and 8th months postpartum, while the maximum levels were observed during the 17th month postpartum. Regarding seasonal variation, the highest daily milk yield was recorded during summer (June), whereas the lowest was found in winter (December). In contrast, the maximum and minimum contents of fat and protein were observed during winter (December) and summer (July), respectively. Similarly, total solids content was maximum in January and minimum in August. Parity had no effect on daily milk yield, while all chemical components were higher in milk from primiparous than multiparous camels. Calf sex and management system did not affect the milk yield and composition. These results are useful in order to develop feeding strategies and breeding programs for improving milk production.

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105.
Escherichia coli O157 is often associated with hemorrhagic colitis and the hemolytic uremic syndrome (HUS). The verocytotoxins are considered to be the major virulence determinants. However, vt-negative E. coli O157 were recently isolated from patients with HUS. Several transmission routes to humans are described, but cattle feces are the primary source from which both the food supply and the environment become contaminated with E. coli O157.In a prevalence study performed on dairy, beef, mixed dairy/beef and veal farms in the summer of 2007, vt-negative isolates were detected on 11.8% (8/68) of the positive farms. From these eight farms, a total of 43 sorbitol-negative E. coli O157:H7 were collected. On five farms, only strains negative for the vt genes were present whereas both vt-negative and vt-positive strains could be detected on three other farms. Further characterization revealed that all isolates carried the eaeA and hlyA genes. Pulsed-field gel electrophoresis (PFGE) of all isolates resulted in nine different PFGE types and within the vt-negative strains, four different genotypes were identified, indicating that certain genetic clones are widespread over the cattle population.  相似文献   
106.
A field study was conducted at the Research Farm of NWFP, Agricultural University, Pakistan. Chickpea (Cicer aeritinum L.) cultivar, ‘Hassan-2000’, was sown as a winter crop under conventional tillage (CT) or no-tillage (NT) dryland systems in a randomized complete block design with split plot arrangement using four replications. Three levels of phosphorus (P; 0, 80 and 120 kg P2O5 ha?1) were broadcast applied at the time of last plowing and were thoroughly mixed in subplot size of 1.8 × 5 m. About 20% less weed biomass and 2% higher grain yield was recorded under CT than in NT. Plots supplied with P2O5 had higher value of the all the parameters under study except number of plant m?2 when compared with control (no P applied). However, the grain yield response to P beyond 80 kg ha?1 was not positive. CT + 80 kg P2O5 ha?1 was identified as the optimum level for maximum chickpea production under the existing dryland condition where application of herbicides in NT is not possible. Further experiments to study the optimization of P in chickpea production under dryland conditions are required.  相似文献   
107.
Greenbelts are effective tools for mitigation of traffic induced air and noise pollution. In this study, the potential role of greenbelts along the roadside for the reduction of air pollution and noise levels has been assessed by using seasonally monitored data in a megacity of Bangladesh. Correlation analysis was performed between the vegetation status, measured by canopy density and shelterbelt porosity, and the total suspended particles (TSP) removal percentage. Further, the reduction of noise level was also analyzed. The results showed that the greenbelts greatly contributed to reduce TSP pollution and it was as much as 65%. Noise level reduction was also achieved up to 17 dB when compared to the open area. Moreover, TSP removal percentage was correlated to the crown density. Area having higher crown density demonstrated less air pollution and lower level of noise compared to the area having lower crown density. Greenbelt showed better performance in summer time than winter.  相似文献   
108.
For the users' convenience of accessing the AGRIS resources quickly and using them fully,the paper decomposes the structure of AGRIS Search net,analyzes the users' requirement met for conducting a bili...  相似文献   
109.
In the tropical arid and semi-arid regions of many developing countries, sheep are predominantly grazed on low-quality pastures and stall-fed on crop residues. This study evaluated the potential of Grewia oppositifolia tree leaves as crude protein (CP) supplement to the low-quality diets of sheep in comparison with cottonseed cake (CSC). Changes in the chemical composition of the leaves with progressive maturation (December to March) were studied. The leaves maintained a high CP content (>164?g/kg dry matter (DM)) during the prolonged maturation in the winter feed scarcity period. The leaves were rich in Ca (41?g/kg DM) and K (89?g/kg DM). The rate of degradation and effective degradability of CP were consistently higher (P?相似文献   
110.
This paper reports the immunostimulatory and protective effects of Aloe vera extracts (aqueous and ethanolic) against coccidiosis in industrial broiler chickens. The study was divided into two experiments. Experiment-I was conducted for the evaluation of immunostimulatory activity of A. vera and experiment-II demonstrated the protective efficacy of A. vera extracts against coccidiosis in chickens. Results of the experiment-I revealed significantly higher (p<0.05) lymphoproliferative responses in chickens administered with ethanolic extract of A. vera as compared to those administered with aqueous extract and control group. Microplate haemagglutination assay for humoral response on day 7th and 14th post primary and secondary injections of sheep red blood cells (SRBCs) revealed significantly higher (p<0.05) anti SRBC antibody (total Igs, IgG and IgM) titers in chickens of experimental groups as compared to the control group. None of the extracts, however, demonstrated significant effects on the development of lymphoid organs. Results of experiment-II revealed maximum protection (60%) in chickens administered with aqueous Aloe extract as compared to the ethanolic extract administered chickens (45%). Mean oocysts per gram of droppings in the control group was significantly higher (p<0.05) as compared to the chickens in both the experimental groups. Chickens administered with aqueous Aloe extract showed a minimal mean lesion score (2.3) followed by those administered with ethanolic Aloe extract (2.6) and control chickens (3.05) for caeca, and a similar pattern was observed for intestinal lesion scoring. Further, significantly higher weight gains and antibody titers (p<0.05) were observed in chickens administered with A. vera extracts as compared to those in the control group. It was concluded that A. vera may be a potential and valuable candidate to stimulate the immune responses and can be used successfully as an immunotherapeutic agent against coccidiosis in industrial broiler chickens.  相似文献   
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