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101.
102.
Raquel Lunedo Luiz R. Furlan Miguel F. Fernandez‐Alarcon Gustavo H. Squassoni Daniel M. B. Campos Dani Perondi Marcos Macari 《Journal of animal physiology and animal nutrition》2019,103(4):1070-1080
The present study was conducted to verify how feed restriction affects gut microbiota and gene hepatic expression in broiler chickens and how these variables are related to body weight gain. For the experiment, 21‐d‐old Cobb500TM birds were distributed in a completely randomized experimental design with three treatments: T1. Control (ad libitum—3.176 Mcal/kg ME—metabolizable energy—and 19% CP—crude protein); T2. Energetic restriction (2.224 Mcal/kg ME and 19% CP) from 22 to 42 days with consumption equivalent to control; T3. Quantitative restriction (70% restriction, i.e., restricted broilers ingested only 30% of the quantity consumed by the control group—3.176 Mcal/kg ME and 19% CP) for 7 days, followed by refeeding ad libitum from 28 to 42 days. Ileum and caecum microbiota collections were made at 21, 28 and 42 days of age. Hepatic tissue was collected at 28 and 42 days old for relative gene expression analyses. At 43‐d‐old, body composition was quantified by DXA (Dual‐energy X‐ray Absorptiometry). Both feed restriction programmes decreased Lactobacillus and increased Enterococcus and Enterobacteriaceae counts. No differences were found in the refeeding period. Energetic restriction induced the expression of CPT1‐A (Carnitine palmitoyltransferase 1A) gene, and decreased body fat mass. Quantitative feed restriction increased lipogenic and decreased lipolytic gene expression. In the refeeding period, CPT1‐A gene expression was induced, without changing the broilers body composition. Positive associations were found between BWG (Body Weight Gain) and Lactobacillus and Clostridium cluster IV groups, and negatively associations with Enterobacteriaceae and Enterococcus bacterial groups. In conclusion, differences found in microbiota were similar between the two feed restriction programmes, however, hepatic gene expression differences were only found in quantitative restriction. Higher counts of Lactobacillus and Clostridium cluster IV groups in ileum are likely to be related to better broiler performance and low expression of lipogenic genes. 相似文献
103.
Jef Dupain Janet Nackoney J. Mario Vargas Paul J. Johnson Miguel A. Farfán Mange Bofaso Julia E. Fa 《Biological conservation》2012,146(1):32-40
Ever-increasing rates of subsistence and commercial bushmeat hunting in African moist forests result in unsustainable exploitation levels for many mammals. Bushmeat markets are found in a large number of human settlements throughout the region and may be used to monitor the state of game species in catchment areas. As depletion of large-bodied species forces hunters to focus on small-bodied species this is likely to be reflected in the mean body mass and species composition of animals sold in that market. In this paper we present data on bushmeat sold in Basankusu market in the Democratic Republic of Congo during a 2-year period (276 sample days). We counted 10,358 carcasses of 33 mammal taxa, emerging from nine well-defined hunting catchment zone; an area of more than 45,000 km2. For each catchment we assessed human pressures using metrics derived from remote sensing. Human population density correlated with higher species richness of species harvested, as well as with an increase in rarer taxa, and with a tendency for more individuals with higher intrinsic rates of reproduction to be observed. We suggest that simple surrogates of anthropogenic pressure and faunal characteristics in markets can be used as a rapid tool to measure faunal depletion of mammals at a regional scale. Such a system of evidence-based game monitoring would allow identification of both potentially overhunted and of less-disturbed areas for consideration in strategic planning. 相似文献
104.
Fernanda Bortolini Miguel Dall’Agnol Maria Teresa Schifino-Wittmann 《Genetic Resources and Crop Evolution》2006,53(5):1081-1087
White clover is one of the most important forage legume species worldwide, playing an important role in Southern Brazil temperate
cultivated pastures. This work was aimed to characterize the genetic variability of the USDA white clover core collection
formed by 78 accessions representing 50 countries, together with two very well known cultivars (Huia and Ladino Regal), using
RAPD (Random Amplified Polymorphic DNA) markers to produce genetic fingerprints. There were used DNA bulks formed by the extraction
and mixture of 20 random individuals from each accession. Twenty four primers were used, which revealed from 3 to 29 bands,
forming a total of 371 polymorphic bans and only one monomorphic, ranging from 50 to 3098 bp. The results showed a genetic
similarity among the accessions, ranging from 0.18 to 0.58 (Jaccard’s index), with an average of 0.24, allowing the identification
of each individual accession using just three primers. The results also showed a large genetic variability within the white
clover core collection, probably due to its reproduction mode and ploidy level, which could be used in plant breeding program. 相似文献
105.
Louisa Wessels Perelo Miguel Jimenez Jean Charles Munch 《Soil biology & biochemistry》2006,38(5):912-922
Microbial biomass N dynamics were studied under field and laboratory conditions in soils of high yield (HY) and low yield (LY) areas in an agricultural field. The objective of the study was to determine the size and activity of soil microbial biomass in the soils of the different yield areas and to compare these data obtained under field and laboratory conditions. Soils were amended with 15N labelled mustard (Sinapis alba) residues (both experiments) and labelled nitrate (laboratory only) at 30 μg N g−1 dry soil. Soil microbial biomass (SMB) N, mineral N (Nmin) and total N content was monitored both in the field and in the laboratory. N2O efflux was additionally measured in laboratory treatments. Isotope ratios were determined for SMB in both experiments, for all other parameters only in the laboratory treatments. In the laboratory less amounts of added substrate N were immobilised by the SMB in HY soils compared to LY soils, whereas in the field immobilisation of added N by SMB was higher in HY soils initially and slightly lower after 40 days of incubation. Calculated turnover times in the laboratory nitrate, laboratory mustard and field mustard amendments were 0.18, 0.27 and 0.74 years (HY) and 0.22, 0.61 and 1.01 years (LY), respectively. The turnover times of added substrate N always showed the trend to be faster in HY soils compared to LY soils. A faster turnover of nutrients in the HY soils may involve a better nutrient supply of the plants, which coincides with the higher agricultural yield observed in these areas. 相似文献
106.
Populations of the flea beetle, Phyllotreta cruciferae Goeze (Coleoptera:Chrysomelidae), were greater in weed-free collards than in collard monocultures and polycultures (intercropped with beans) left weedy for 2 or 4 weeks after transplanting or for the entire season. Flea beetle densities and amount of leaf damage per individual collard plant were significantly lower in the plots with crucifer weeds (mainly Brassica campestris L.), possibly because the beetles preferred to feed and/or concentrate on this plant rather than on collards. 相似文献
107.
Giner E Andújar I Recio MC Ríos JL Cerdá-Nicolás JM Giner RM 《Journal of agricultural and food chemistry》2011,59(24):12882-12892
Oleuropein, the major secoiridoid in olive tree leaves, possesses a wide range of health promoting properties. It has recently been shown to exhibit anti-inflammatory activity. We have evaluated the effect of oleuropein on dextran sulfate sodium (DSS)-induced experimental colitis in mice in order to provide insight into its mechanisms of action. Oral administration of oleuropein notably attenuated the extent and severity of acute colitis while reducing neutrophil infiltration; production of NO, IL-1β, IL-6, and TNF-α; expression of iNOS, COX-2, and MMP-9; and the translocation of the NF-κB p65 subunit to the nucleus in colon tissue. In LPS-stimulated peritoneal macrophages, the oleuropein metabolite, hydroxytyrosol, was shown to inhibit NO production, iNOS expression, NF-κB p65 subunit translocation, mRNA expression, and the release of IL-1β, IL-6, and TNF-α. These results suggest that the effect of oleuropein on DSS-induced colitis is associated with a decrease in the production of interleukins and expression of proteins, principally through reduction of NF-κB activation. 相似文献
108.
109.
Improvement of table grapes quality and safety by the combination of modified atmosphere packaging (MAP) and eugenol, menthol, or thymol 总被引:1,自引:0,他引:1
Valverde JM Guillén F Martínez-Romero D Castillo S Serrano M Valero D 《Journal of agricultural and food chemistry》2005,53(19):7458-7464
Table grape is a nonclimacteric fruit that shows a rapid loss of quality during storage and is very susceptible to colonization by fungi, especially Botrytis cinerea, which is considered the most important disease of this commodity. To solve this problem, synthetic fungicides have been used, although legal restrictions and consumer's concern demand the search of other safe means. In the present paper, and as an alternative of synthetic fungicides, an active packaging to improve MAP effectiveness on preserving table grape (cv. Crimson Seedless) quality and safety was developed by the addition of 0.5 mL of eugenol, thymol, or menthol inside the packages. Packages were stored at 1 degree C for 35 days. The final gas composition inside the packages was 1.4-2.0 and 10.0-14.5 kPa of CO(2) and O(2), respectively, with no significant slight differences among treatments. Results showed that the addition of eugenol, thymol, or menthol improved the beneficial effect of MAP in terms of delaying weight loss and color changes, retarding degrees Brix/acidity ratio evolution, and maintaining of firmness. Thereafter, these treatments showed additional benefit in terms of delayed rates of rachis deterioration and berry decay. Finally, the total viable counts for both mesophilic aerobics and especially yeast and molds were significantly reduced in the grapes packaged with the natural antimicrobial compounds. All of the above effects led to maintenance of table grape quality and safety for longer storage periods (3 additional weeks as compared to controls under MAP only). 相似文献
110.
Miguel Urrestarazu Pilar Carolina Mazuela Gabino Alberto Martínez 《Journal of plant nutrition》2013,36(11):2031-2043
Certain ecologically-friendly substrates have recently been shown to be perfectly viable alternatives to other more traditional ones such as rockwool, perlite, or some hydroponic systems. However, in order to be competitive for vegetable production in the Mediterranean region, substrates must be used for at least one year. The present study assessed random samples of two commercial substrates, almond shell and compost from greenhouse vegetable residue. The substrates were evaluated as growing media for long-term soilless production. Three experiments were conducted to evaluate the effects of reusing these substrates, comparing them with rockwool in terms of yield and fruit quality characteristics of melon and tomato. The physical, physico-chemical, and chemical properties studied differed significantly on reutilizing these materials. However, these differences did not prove to be limiting factors when fertigation parameters applied were adjusted according to substrate properties. The results suggest that compost and commercial almond shells seem to be acceptable growing media after at least 265 and 530 days of reutilization, respectively. 相似文献