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91.
92.

Background

Periodic lack of availability and high cost of commercially produced isotonic fluids for intravenous (IV) use in horses have increasingly led to use of home‐made or commercially compound fluids by veterinarians. Data regarding the quality control and safety of compounded fluids would be of benefit to equine veterinarians.

Objectives

To compare electrolyte concentrations, sterility, and endotoxin contamination of commercially available fluids to 2 forms of compounded isotonic crystalloid fluids intended for IV use in horses.

Methods

Prospective study. Two methods of preparing compounded crystalloids formulated to replicate commercial Plasma‐Lyte A (Abbott, Chicago, IL) were compared. One formulation was prepared by a hand‐mixed method involving chlorinated drinking water commonly employed by equine practitioners, and the other was prepared by means of ingredients obtained from a commercial compounding pharmacy. The variables for comparison were electrolyte concentrations, sterility, and presence of endotoxin contamination.

Results

Electrolyte concentrations were consistent within each product but different between types of fluids (P < 0.0001). Hand‐mixed fluids had significantly more bacterial contamination compared to commercial Plasma‐Lyte A (P = 0.0014). One of the hand‐mixed fluid samples had detectable endotoxin contamination.

Conclusions and Clinical Importance

Chlorinated drinking water is not an acceptable source of water to compound isotonic fluids for IV administration. Equine practitioners should be aware of this risk and obtain the informed consent of their clients.  相似文献   
93.
The identification of 163 strains of Mycobacterium bovis by polymerase chain reaction (PCR) and microbiological tests was carried out on 252 tuberculous-like lesions (TLLs) collected from slaughtered cattle in south-east Brazil. This study compared the usefulness of three genotyping techniques, IS6110-restriction fragment length polymorphism (RFLP), polymorphic guanine-cytosine-rich sequence (PGRS)-RFLP and direct repeat (DR)-spoligotyping, as applied to M. bovis isolates. Based on IS6110-RFLP genotyping we selected a group of 23 isolates containing more than one IS6110 copy, along with 16 samples containing one IS6110 copy from different geographical areas, evenly distributed among dairy (eight) and beef cattle (eight). These selected isolates were analysed by PGRS-RFLP and DR-spoligotyping genotyping. Dairy cattle (17%) display a higher frequency of multiple IS6110 copies than beef cattle (10%). A comparison between the genotype data obtained fails to show a correlation between the main clusters found by the three techniques. However, the clustering of each genotyping procedure revealed that the majority of strains are closely related. The RFLP-PGRS patterns showed a sizable group (20.5%) containing a 5.5 kb fragment and the predominant spoligotype is similar to that from the BCG vaccine strain. Unexpectedly, four strains (2.4%) showed drug resistance to 0.2 microg/ml isoniazid and 20 microg/ml ethionamide, but none of them was resistant to rifampicin or other antibiotics tested.  相似文献   
94.
95.
Sulfated polysaccharides (SPS) from seaweeds have great biochemical and biotechnological potential. This study aimed to investigate the effect of SPS isolated from the seaweed Caulerpa sertularioides on adipogenic differentiation as a possible alternative treatment for obesity. The SPS-rich extract from the seaweed C. sertularioides was fractioned into three SPS-rich fractions (F0.5; F0.9; and F1.8) chemically characterized. Among these four samples, only F0.9 showed a significant inhibitory effect on adipogenesis of 3T3-L1 preadipocytes. Ten SPS-rich fractions were isolated from F0.9 through ion-exchange chromatography. However, only the fraction (CS0.2) containing a sulfated glucan was able to inhibit adipogenesis. CS0.2 reduces lipid accumulation and inhibits the expression of key adipogenic (PPARγ, C/EBPβ, and C/EBPα) and lipogenic markers (SREBP-1c, Fabp4, and CD36). The data points to the potential of sulfated glucan from C. sertularioides for the development of functional approaches in obesity management.  相似文献   
96.
Cowpea (Vigna unguiculata (L.) Walp.) is one of the most important crops in the north and northeast regions of Brazil, where it is grown under the subsistence regime, mainly because of its adaptation to the local edaphoclimatic conditions. This species is an important legume in Brazil because of its significant nutritional value in the diet of low-income populations. Moreover, it is able to benefit from the process of biological nitrogen fixation, which leads to a significant reduction in production costs. The objective of this research was to evaluate the agronomic efficiency of bacterial strains approved by the Ministry of Agriculture, Livestock and Supply for commercial inoculant production when in symbiosis with cowpea in a Rhodic Eutrudox in Lavras, MG, as well as to identify and verify the efficiency of the native populations that nodulate cowpea. Agronomic efficiency of nitrogen-fixing nodulating bacterial strains (UFLA 03-84, INPA 03-11B, and BR 3267) in symbiosis with cowpea was evaluated in the field. Subsequently, the efficiency and diversity of isolates from the nodules obtained in the field were evaluated under greenhouse conditions. The genetic diversity of the efficient isolates was determined by partial sequencing of the 16S rRNA gene. Grain yields obtained by the inoculation of seeds in the field with the strains were similar to those of the controls without inoculation with and without mineral N addition indicating the existence of efficient native populations. In the native community, we identified isolates with similar or higher efficiency than the strains approved for cowpea inoculation and the control that received mineral N. The isolates subjected to partial sequencing of the 16S rRNA gene were phylogenetically related to the Bradyrhizobium genus.  相似文献   
97.
This study aimed to evaluate various concentrations of egg yolk (5, 10, or 20%) in combination with different concentrations of glycerol (3% or 6%) added to a Tris‐based extender on the post‐thaw characteristics of sperm obtained from Tayassu tajacu. For this purpose, semen from 10 sexually male mature collared peccaries was collected by electroejaculation and evaluated for sperm motility, vigour, viability, morphology and functional membrane integrity. The ejaculates were initially extended in Tris‐fructose plus egg yolk (5%, 10% or 20%). After cooling, the semen was added to Tris‐egg yolk plus glycerol (6% or 12%), resulting in a final concentration of 3% or 6% glycerol of the extender. Straws were frozen using liquid nitrogen and thawed in a water bath at 37°C for 30 s. The frozen–thawed semen was evaluated as reported for fresh semen. After thawing, a significant decrease was verified for sperm motility and vigour, for all the samples in comparison with fresh semen. However, no differences were evidenced among treatments for any sperm characteristics evaluated (p > 0.05), except for the combination between 10% egg yolk and 6% glycerol, which provided the worst preservation of functional membrane integrity (p < 0.05). The interactions between higher concentrations of egg yolk (20%) and glycerol (6%) and also between lower concentrations of the same substances (5% egg yolk and 3% glycerol) added to the Tris‐based extender negatively affected the preservation of the normal sperm morphology after thawing (p < 0.05). In conclusion, the use of Tris‐based extender added to 10% or 20% egg yolk plus 3% glycerol is recommended for effective sperm cryopreservation in collared peccaries.  相似文献   
98.
Phosphorus (P) is required by crop plants for many physiological and biochemical functions. Knowledge of phosphorus uptake and its use by crop plants is essential for adequate management of this essential nutrient. A field experiment was conducted during four consecutive years to determine P uptake and use efficiency by upland rice, dry bean, corn and soybean grown in rotation on a Brazilian Oxisol. Plant samples were taken at different growth stages during the growth cycle of each crop for phosphorus analysis. Phosphorus concentration (content per unit dry matter) significantly decreased in a quadratic fashion with the advancement of plant age in four crop species. Phosphorus concentration was higher in legumes compared to cereals. Phosphorus uptake in shoot, however, significantly increased in an exponential quadratic fashion with the advancement of plant age of crop species. At harvest, P uptake was higher in grain compared to shoot, indicating importance of this element in improving crop yields. Phosphorus use efficiency (grain or straw yield per unit P uptake) was higher in cereals compared to legumes. The P use efficiency for grain production was 465 kg kg?1 for upland rice, 492 kg kg?1 for corn, 229 kg kg?1 for dry bean and 280 kg kg?1 for soybean. The higher P use efficiency in cereals was associated with higher yield of cereals compared to legume species.  相似文献   
99.
The identification of 163 strains of Mycobacterium bovis by polymerase chain reaction (PCR) and microbiological tests was carried out on 252 tuberculous‐like lesions (TLLs) collected from slaughtered cattle in south‐east Brazil. This study compared the usefulness of three genotyping techniques, IS6110‐restriction fragment length polymorphism (RFLP), polymorphic guanine‐cytosine‐rich sequence (PGRS)‐RFLP and direct repeat (DR)‐spoligotyping, as applied to M. bovis isolates. Based on IS6110‐RFLP genotyping we selected a group of 23 isolates containing more than one IS6110 copy, along with 16 samples containing one IS6110 copy from different geographical areas, evenly distributed among dairy (eight) and beef cattle (eight). These selected isolates were analysed by PGRS‐RFLP and DR‐spoligotyping genotyping. Dairy cattle (17%) display a higher frequency of multiple IS6110 copies than beef cattle (10%). A comparison between the genotype data obtained fails to show a correlation between the main clusters found by the three techniques. However, the clustering of each genotyping procedure revealed that the majority of strains are closely related. The RFLP‐PGRS patterns showed a sizable group (20.5%) containing a 5.5 kb fragment and the predominant spoligotype is similar to that from the BCG vaccine strain. Unexpectedly, four strains (2.4%) showed drug resistance to 0.2 μg/ml isoniazid and 20 μg/ml ethionamide, but none of them was resistant to rifampicin or other antibiotics tested.  相似文献   
100.
Agricultural land abandonment, widespread in the Mediterranean, is leading to a recovery of scrubland and forests which are replacing open habitats and increasing wildfire events. Using published data, we modelled the global and regional impact of abandonment and wildfires on 554 species of terrestrial vertebrates occurring in Mediterranean Europe. For all groups except amphibians, open habitats or farmland sustained higher species richness. Open habitats showed regional differences in their conservation value, western areas being particularly important for birds and amphibians and eastern areas for reptiles. Scrublands hosted fewer species than open habitats, farmland and forest, but sustained several endemic birds and mammals. The greater species richness of forests was mostly due to species widespread in Europe. Wildfires promote scrubland expansion in detriment of forest; because more species are associated to eastern forests, fire is predicted to affect more seriously this region. Scrubland conservation value was found to be highest in the west, where fire might have a positive impact. Fire regime, however, plays a crucial role. Although large fires have a negative impact, small-scale fires may favour biodiversity in abandoned areas. Due to the intrinsic difficulty in managing abandoned land to preserve the original Mediterranean vertebrate diversity, the best option to achieve this goal is the development of policies designed to make farmers and traditional farmland survive.  相似文献   
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