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61.
This study was conducted to evaluate the effect of electron beam‐irradiated cottonseed meal on performance, carcass characteristics and some blood parameters of broiler chicks. Treatments were cottonseed meal (CSM) at levels of 12% and 24% (raw and irradiated at 30 kGy) and corn‐soya bean meal diet (as control, without CSM and without irradiation) that used with five dietary treatments, four replicates and 10 birds of each for 42 days in completely randomized design. Feed intake (FI) and body weight gain (BWG) were recorded weekly. At 42 days of age, two birds per pen were randomly selected for the determination of carcass characteristics and blood parameters. BWG decreased with increasing levels of dietary CSM during the experiment (p < 0.05). In addition, radiation had significant positive effect in broilers fed 12% compared with those fed 24% CSM. FI in chicks fed control and diet containing 24% CSM were increased significantly in starter period. But FI was significantly decreased in broilers consumed CSM compare to the control in grower and during the experiment. Feed conversion ratio (FCR) increased with increasing levels of CSM in the diets. Relative weights of liver, gastrointestinal tract (GI), pancreas, gizzard and abdominal fat were increased by increasing levels of CSM in the diet (p < 0.05). Glucose, cholesterol, HDL, triglyceride and phosphorous concentrations increased, and LDL concentration decreased as the dietary CSM levels increased (p < 0.05). But radiation had not significant effect on blood parameters. Electron irradiation seems to be a good procedure to improve the nutritional quality of CSM, but it seems higher dose of it was needed to improve performance of chickens.  相似文献   
62.
Valente  João  Sari  Bilal  Kooistra  Lammert  Kramer  Henk  Mücher  Sander 《Precision Agriculture》2020,21(6):1366-1384
Precision Agriculture - Knowing before harvesting how many plants have emerged and how they are growing is key in optimizing labour and efficient use of resources. Unmanned aerial vehicles (UAV)...  相似文献   
63.
The randomly amplified polymorphic DNA (RAPD) technique was used to develop strain-specific primers for Gliocladium catenulatum strain J1446, which is promising in biological control. One of the primer pairs developed proved to be strain-specific; strain J1446 was differentiated from 16 G. catenulatum strains and six other strains of two Gliocladium species, as well as from Trichoderma virens, and isolates of Nectria spp. and Fusarium spp. Specific primers were also tested with DNA isolated from cucumber leaves, treated or untreated with a solution made from Gliocladium powder. The expected amplification product was produced only from treated leaves. DNA isolated from Gliocladium-treated potato tubers and fungi grown in peat was also used in amplification reactions. Strain-specific primers detected strain J1446 when the amount of DNA was 5pg or more. Some variation between the Gliocladium strains was found by the random amplified microsatellites method (RAMS) and the universally primed polymerase chain reaction method (UP-PCR), but no clear fragments specific to strain J1446 were produced. Cross-blot hybridisation of UP-PCR products differentiated strain J1446 from T. virens, but not from the Gliocladium isolates. The 28S rDNA sequences and -tubulin sequences were identical or very similar in all Gliocladium strains. Thus, it is possible that the Gliocladium strains of the present study are conspecific, which means that a revision in the taxonomy of Gliocladium species may be necessary.  相似文献   
64.
A real-time PCR technique was applied for the quantification of trichothecene-producing Fusarium species (TMTRI assay) as well as the highly toxigenic Fusarium graminearum (TMFg12 assay) present in barley grain and malt. PCR results were compared to the amounts of trichothecenes detected in the samples to find out if the PCR assays can be used for trichothecene screening instead of expensive and laborious chemical analyses. DNA was extracted from ground kernels using a commercial DNA extraction kit and analysed in a LightCycler® system using specific primers and fluorogenic TaqMan probes. Both naturally and artificially contaminated grains were analysed. The TMTRI assay and the TMFg12 assay enabled the quantification of trichothecene-producing Fusarium DNA and F. graminearum DNA present in barley grain and malt samples, respectively. Both TaqMan assays were considered to be sensitive and reproducible. Linearity of the assays was 4–5 log units when pure Fusarium DNAs were tested. The amount of Fusarium DNA analysed with the TMTRI-trichothecene assay could be used for estimation of the deoxynivalenol (DON) content in barley grain. Furthermore, the TMFg12 assay for F. graminearum gave a good estimation of the DON content in north American barley and malt samples, whilst the correlation was poor among Finnish samples. DON content and the level of F. graminearum DNA were found to be naturally low in Finnish barleys.  相似文献   
65.
Eurasian Soil Science - Splash erosion, the first step in water erosion process, occurs because of raindrops collusion with soil aggregates and pushing soil particulates into the air. The objective...  相似文献   
66.
The spherical mean of the shoot silhouette-to-total leaf area ratio (STAR) and the shoot transmission coefficient (c) are two key structural parameters in radiative transfer models for calculating canopy photosynthesis and leaf area index. The standard optical method for estimating these parameters might introduce errors in the estimates for species with flexible shoots and needles by changing shoot inclination relative to its inclination in situ. We devised and tested two methods to address this problem. First, we modified the standard optical method by designing an apparatus that allows shoots to be photographed in their original orientation. Second, we developed a faster, model-based approach to replace photography and tested the results against the established approach. We used shoots of three pine species, Pinus echinata Mill. (needle length ~50 mm), P. taeda L. (~150 mm) and P. palustris Mill. (~300 mm). Values of the parameters simulated by the model were similar to those measured from the photographs. In our data, STAR varied about twofold among the pine species and was ~40% higher in shade shoots than in sun shoots of P. taeda. The transmission coefficient for P. taeda shade shoots was also ~40% higher than that of sun shoots of all three species. We tested the versatility of the model by employing it on shoots of two other pine species (P. strobus L. and P. thumbergiana Parl.) as well as on shoots of Tsuga canadensis L. Carr. and Picea pungens Engelm. Regardless of shoot characteristics, the model generated values of shoot structural parameters similar to those estimated with the optical method. Although species-specific and vertical gradients in parameter values are best for modeling radiative transfer in conifer canopies, our results suggest that, in the absence of adequate data, STAR can be approximated as 0.16 for a wide range of shoot structures. For applications requiring angle-dependent parameterization, our new model facilitates rapid generation of these radiative transfer parameters.  相似文献   
67.
68.
OBJECTIVE: Paternal smoking is highly prevalent in Asia, and tobacco may account for a large proportion of household expenditures among poor families. We sought to characterise the relationship between paternal smoking, child malnutrition and food expenditures. DESIGN: Data on smoking, household expenditures and child malnutrition were examined in a stratified multistage cluster sample of households in the Indonesia nutrition surveillance system. Main outcome measures were child wasting (weight-for-height Z-score < - 2), underweight (weight-for-age Z-score < - 2) and stunting (height-for-age Z-score < - 2), and severe wasting, underweight and stunting (defined by respective Z-scores < - 3). SETTING: In total, 175,583 households from urban slum areas in Indonesia. SUBJECTS: Children 0-59 months of age. RESULTS: The prevalence of paternal smoking was 73.8%. After adjusting for child gender and age, maternal age and education, and weekly per capita household expenditures, paternal smoking was associated with child stunting (odds ratio (OR) = 1.11, 95% confidence interval (CI) 1.08-1.14, P < 0.0001), severe wasting (OR = 1.17, 95% CI 1.03-1.33, P = 0.018) and severe stunting (OR = 1.09, 95% CI 1.04-1.15, P < 0.001). In households where the father was a smoker, tobacco accounted for 22% of weekly per capita household expenditures, with less money spent on food compared with households in which the father was a non-smoker. CONCLUSIONS: Among poor families in urban slum areas of Indonesia, paternal smoking diverts household money from food to tobacco and exacerbates child malnutrition.  相似文献   
69.
70.
Management may influence abiotic environments differently across time and spatial scale, greatly influencing perceptions of fragmentation of the landscape. It is vital to consider a priori the spatial scales that are most relevant to an investigation, and to reflect on the influence that scale may have on conclusions. While the importance of scale in understanding ecological patterns and processes has been widely recognized, few researchers have investigated how the relationships between pattern and process change across spatial and temporal scales. We used wavelet analysis to examine the multiscale structure of surface and soil temperature, measured every 5 m across a 3820 m transect within a national forest in northern Wisconsin. Temperature functioned as an indicator – or end product – of processes associated with energy budget dynamics, such as radiative inputs, evapotranspiration and convective losses across the landscape. We hoped to determine whether functional relationships between landscape structure and temperature could be generalized, by examining patterns and relationships at multiple spatial scales and time periods during the day. The pattern of temperature varied between surface and soil temperature and among daily time periods. Wavelet variances indicated that no single scale dominated the pattern in temperature at any time, though values were highest at finest scales and at midday. Using general linear models, we explained 38% to 60% of the variation in temperature along the transect. Broad categorical variables describing the vegetation patch in which a point was located and the closest vegetation patch of a different type (landscape context) were important in models of both surface and soil temperature across time periods. Variables associated with slope and microtopography were more commonly incorporated into models explaining variation in soil temperature, whereas variables associated with vegetation or ground cover explained more variation in surface temperature. We examined correlations between wavelet transforms of temperature and vegetation (i.e., structural) pattern to determine whether these associations occurred at predictable scales or were consistent across time. Correlations between transforms characteristically had two peaks; one at finer scales of 100 to 150 m and one at broader scales of >300 m. These scales differed among times of day and between surface and soil temperatures. Our results indicate that temperature structure is distinct from vegetation structure and is spatially and temporally dynamic. There did not appear to be any single scale at which it was more relevant to study temperature or this pattern-process relationship, although the strongest relationships between vegetation structure and temperature occurred within a predictable range of scales. Forest managers and conservation biologists must recognize the dynamic relationship between temperature and structure across landscapes and incorporate the landscape elements created by temperature-structure interactions into management decisions.  相似文献   
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