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121.

Background

The identification of serum biomarkers of lung inflammation would facilitate the diagnosis of inflammatory airway disease (IAD) in horses.

Hypothesis

Horses with IAD have higher serum concentrations of markers of inflammation compared to controls.

Animals

Twelve horses with IAD and 10 control horses.

Methods

This was a prospective case–control study. Blood and BALF were collected from horses with IAD and controls. Serum concentration of surfactant protein D (SP‐D), haptoglobin, serum amyloid A (SAA) and of the soluble form of triggering receptor expressed on myeloid cells 1 (sTREM‐1) was measured using commercial ELISA tests.

Results

Horses with IAD had higher serum concentration (log‐transformed values) of SP‐D (mean ± SD: 1.773 ± 0.51), haptoglobin (6.657 ± 0.202) and SAA (0.128 ± 0.396) compared to controls (0.942 ± 0.226, 6.38 ± 0.22, −0.398 ± 0.319, respectively; P < .01 for all). Furthermore, the concentrations of SP‐D and haptoglobin combined allowed differentiating the 2 groups (IAD: 8.43 ± 0.564, controls: 7.322 ± 0.249, P < .0001) with a sensitivity and specificity of 100% when a cut‐off of 7.70 (log value) was employed.

Conclusions and Clinical Importance

Surfactant protein D and haptoglobin serum concentrations could be a diagnostic aid in IAD. Further studies are necessary to establish the specificity of our findings before they can be applied in everyday practice.  相似文献   
122.
Total replacement of fishmeal using marine co‐product meals in the diets for white shrimp Litopenaeus vannamei and its effects on growth, feed utilization and muscle HUFA and sterol composition were assessed in a 45‐day feeding trial with juvenile shrimp (0.32 g mean initial weight). Eight dietary treatments were tested: a control diet containing fishmeal (FM), a commercial shrimp diet as external reference and six diets where the FM in the control diet was totally replaced by pen shell scallop viscera (Pinna rugosa), squid viscera (Dosidicus gigas) or whole chub mackerel (Scomber japonicus) meals, produced by two methods: (i) cooking followed by grinding and drying and (ii) grinding followed by drying. Survival in all treatments was above 92%, except in the commercial diet (77%). The growth response, feed utilization and chemical composition of shrimp varied among the treatments and were affected in different ways by the by‐products and the meals preparation process. Growth and feed intake were significantly higher in shrimp fed diets containing cooked‐dried squid and pen shell scallop viscera meals, and whole mackerel meal produced by grinding followed by drying. Muscle fatty acid profiles were improved for human consumption when these ingredients were used, compared with the diets containing FM.  相似文献   
123.
This study has investigated the muscle growth of diploid and triploid Atlantic cod (Gadus morhua) juveniles raised in replicate tanks over a period of 29 weeks and analysed at three sampling points (February, June and September). Data for weight, length, condition factor (K), muscle fibre growth and myogenic progenitor cells (MPCs) number were collected and results were analysed in relation to body growth and ploidy status. Diploids were significantly heavier than triploids throughout the trial (~10–20%) and had K in June and September samplings. Over the whole period, the rate of muscle fibres' recruitment was 318 fibres per day and 252 fibres per day for diploid and triploid cod respectively. The larger body weight of diploids resulted in a total number of fast fibre number of 114 979 compared to 91 086 in triploids. The average diameter of the 2.5% of the smallest fibres (2.5th percentile) was higher in diploids than triploids at the start of the trial, with a reversed picture for the average of the upper 2.5% (97.5th percentile) at the end of the trial. The probability density function of the estimated muscle fibre diameters showed similar fibre size distribution between size‐matched diploids and triploids at all sample points. The peak fibre diameter was approximately 25 μm in February and increased to approximately 50 μm in June and September, irrespectively of ploidy. Pax 7 were used as molecular markers for MPCs. A positive correlation between Pax 7+ cells and total body length was observed only among triploid fish at the onset of the experiment.  相似文献   
124.
Location of the self-incompatibility gene on the almond linkage map   总被引:8,自引:0,他引:8  
J. Ballester    R. Bo&#;kovi&#;    I. Batlle    P. Arús    F. Vargas    M. C. de  Vicente 《Plant Breeding》1998,117(1):69-72
A progeny obtained from the almond cross ‘Ferragnès’בTuono’ (Prunus amygdalus Batsch) was used to study the self-incompatibility trait in three different ways: fruit set, pollen tube growth and stylar ribonuclease activity. As expected from the genotypes of the parents, all progeny appeared phenotypically as self-compatible. However, the progeny could be scored for the segregation of stylar ribonuclease isozymes and thus allowed the incompatibility locus to be placed on the almond linkage map.  相似文献   
125.
The effect using biofilm as complementary feed for shrimp (Penaeus vannamei) on the taxonomic and functional profile of its intestinal microbiota was evaluated. Shrimp were cultured for 30 days in two similar low‐water exchange systems, one using commercial feed and the other a combination of commercial feed with biofilm as complementary feed source. Six bacteria phyla were detected in the intestine of shrimp from both treatments (Actinobacteria, Bacteroidetes, Cyanobacteria, Firmicutes, Fusobacteria and Proteobacteria), being Proteobacteria the most abundant (81%–92%). However, this later phylum was significantly less dominant in shrimp fed with biofilm; this drop was associated with a decrease in Vibrio abundance. Differences in the taxonomic profile of bacteria between treatments were also observed through principal component analysis where the diet was the main influencing factor (PC1 72.4%). Regarding functional inference, similarities were detected between treatments. Carbohydrate and energy metabolism were the most abundant functions regardless of time or diet, followed by metabolism of cofactors and vitamins, translation processes, nucleotide metabolism and others. Results suggest that biofilm consumption influenced the taxonomic profile bacteria colonizing the shrimp intestine; however, a functional redundancy was observed despite the use of biofilm as complementary feed. Finally, shrimp fed with biofilm showed a better productive response.  相似文献   
126.
In the Canary Islands a number of factors, both natural and induced by human activity, act on the fragile ecosystems and agricultural land to cause increasing problems with desertification and progressive degradation of soil productivity. the results of an assessment of soil degradation in the Canary Islands, The processes, causes and impacts, are presented in this paper. Although several processes and factors contribute to soil degradation in the Canary Islands, two have been found to exert a greater qualitative influence: (a) accelerated erosion (water and aeolian); (b) salinization-sodification (natural and induced by agricultural use). Approximately 40 per cent of the Canary Islands' land is undergoing rapid erosion. the factors involved May, be grouped into: natural erosion—torrential rainfall, sparse vegetation, high soil erodibility, rugged relief; and erosion due to human activities—unsuitable management of arable soils on the steep slopes, overgrazing and deforestation. About 60 per cent of the surface of the archipelago, including areas given over to intensive agriculture, is affected by salinization.The main factors responsible are: natural—an arid climate and a regime of oceanic winds; and human activities—overexploitation of the aquifers, irrigation with water having a high salt and/or sodium content, intensive monoculture, and excessive and indiscriminate use of chemical fertilizers and other agrochemicals.  相似文献   
127.
Despite QTL mapping being a routine procedure in plant breeding, approaches that fully exploit data from multi-trait multi-environment (MTME) trials are limited. Mixed models have been proposed both for multi-trait QTL analysis and multi-environment QTL analysis, but these approaches break down when the number of traits and environments increases. We present models for an efficient QTL analysis of MTME data with mixed models by reducing the dimensionality of the genetic variance–covariance matrix by structuring this matrix using direct products of relatively simple matrices representing variation in the trait and environmental dimension. In the context of MTME data, we address how to model QTL by environment interactions and the genetic basis of heterogeneity of variance and correlations between traits and environments. We illustrate our approach with an example including five traits across eight stress trials in CIMMYT maize. We detected 36 QTLs affecting yield, anthesis-silking interval, male flowering, ear number, and plant height in maize. Our approach does not require specialised software as it can be implemented in any statistical package with mixed model facilities.  相似文献   
128.
129.
Purpose

The aim of this study was to quantify the contents and stocks of exchangeable and nonexchangeable fractions of potassium (K), calcium (Ca), and magnesium (Mg) after one and three successive Pinus taeda crops without fertilization and to predict the soil supply for further cultivations.

Materials and methods

The soil was analyzed in layers up to 80 cm in two Pinus forests, one at the end of the first cultivation and other at the end of the third successive crop, in a subtropical region in southern Brazil. Stocks of exchangeable and semi-total fractions of K, Ca, and Mg in the soil were calculated, and the potential number of crop rotations of Pinus without fertilization was estimated.

Results and discussion

After three Pinus crops, there was an average reduction of 46.9, 90.8, and 45.5% of exchangeable K, Ca, and Mg fractions respectively. Semi-total Ca content reduced in all depths, and semi-total K contents, in turn, only decreased until 20 cm of depth. The semi-total Mg contents have not been modified over the cultivations. Considering crop management with the export of plant twigs and needles and relying just on the availability of exchangeable Ca, the stocks of these nutrients in the soil would be sufficient for only one more Pinus cultivation, even when considering the absorption of nutrients on an 80-cm soil depth profile.

Conclusions

The management adopted in the region must be modified, replacing the nutrients exported via harvesting, especially Ca. Thus, the establishment of new cultivation of Pinus without fertilization may have its yield impaired, especially by the Ca availability.

  相似文献   
130.
Control of directionality in lambda site specific recombination   总被引:37,自引:0,他引:37  
The simple relation between the substrates and products of site-specific recombination raises questions about the control of directionality often observed in this class of DNA transactions. For bacteriophage lambda, viral integration and excision proceed by discrete pathways, and DNA substrates with the intrinsic property of recombining in only one direction can be constructed. These pathways display an asymmetric reliance on a complex array of protein binding sites, and they respond differently to changes in the concentrations of the relevant proteins. The Escherichia coli protein integration host factor (IHF) differentially affects integrative and excisive recombination, thereby influencing directionality. A four- to eightfold increase in intracellular IHF coincides with the transition from exponential to stationary phase; this provides a mechanism for growth phase-dependent regulation of recombination that makes the cellular physiology an intrinsic part of the recombination reaction.  相似文献   
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