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491.
Peinado RA Moreno JJ Ortega JM Mauricio JC 《Journal of agricultural and food chemistry》2003,51(21):6198-6203
Flor yeast Saccharomyces cerevisiae (capensis G1) strain assimilates gluconic acid during the aerobic biological aging process of sherry wines and exerts significant changes on the final volatile compounds of wines, especially a decrease in volatile acidity and butanoic, isobutanoic, 2-methylbutanoic, and 3-methylbutanoic acids. This decrease may have a favorable effect on the quality of sherry wines. 相似文献
492.
R. Moreno J. A. Espejo A. Cabrera T. Millán J. Gil 《Genetic Resources and Crop Evolution》2006,53(4):729-736
A study has been conducted into the genetic variation analysis of the tetraploid asparagus landrace ‘Morado de Huetor’ and
its relationship with current commercial cultivars using Random Amplified Polymorphic DNA (RAPD) molecular markers. The presence
of different ploidic levels in the ‘Morado de Huetor’ landrace has been also studied using cytogenetic analysis. Ten decamer
oligonucleotides were used to obtain RAPD markers and to characterise 52 individuals of ‘Morado de Huetor’, 7 of the tetraploid
cultivar ‘Purple Passion’, and 55 of 5 diploid hybrid commercial cultivars. Jaccard similarity index was calculated and a
cluster analysis using UPGMA (Unweighted Pair-Group Method using Arithmetic Average) was performed. Tetraploid asparagus,
‘Morado de Huetor’ and ‘Purple Passion’, were well differentiated from the diploid ones showing a higher genetic variability.
This result suggests a different origin for tetraploid and diploid asparagus varieties. Within the diploid cultivars a variety
distribution was obtained. A specific monomorphic band (OPB20883) was found in tetraploid varieties. Within the diploid cultivars, two bands (OPB20830, OPC15705) can be used to distinguish between the hybrid cultivars used in this study. Tri-, penta-, hexa-, and octoploid plants were
found in ‘Morado de Huetor’. The origin of these ploidic levels is discussed and their use in the development of new varieties
is proposed. In conclusion, ‘Morado de Huetor’ is a genetic resource that could be used to increase the narrow genetic background
reported in diploid asparagus cultivars. 相似文献
493.
Eduardo Moreno‐Jiménez Jesús M. Peñalosa Elvira Esteban Ramón O. Carpena‐Ruiz 《植物养料与土壤学杂志》2007,170(4):485-494
Plants of Rumex induratus and Marrubium vulgare, collected in the mining area of Almadén, were transferred to pots and grown for 2 months using perlite as substrate and treated with soluble mercury (Hg) in the applied nutrient solution. Mercury resistance, Hg bioaccumulation, and some stress biomarkers were investigated in both plant species. Mercury concentration increased in both plant species in response to Hg supply, but R. induratus was more effective in Hg accumulation. Rumex induratus and M. vulgare showed higher [Hg]shoot‐to‐[Hg]root ratios than other plant species. Mercury in the growth medium perlite was also investigated, distinguishing soluble, available, and total amounts of Hg in the medium. At the lower doses, one half of the applied Hg was retained by perlite. Rumex induratus decreased the available Hg fraction in perlite more than M. vulgare. The bioaccumulation factor ([Hg]plant/[Hg]available) was similar in both species and similar as found in previous field studies. Plant growth, water content, and chlorophyll concentration, and nutrient translocation were reduced in both plant species by the Hg. Rumex induratus showed higher resistance and Hg‐accumulation capacity than M. vulgare, due to the accumulation of thiols in roots and the absence of a lipid oxidative response. 相似文献
494.
Felipe Bastida José Luis Moreno Teresa Hernández Carlos García 《Soil biology & biochemistry》2006,38(12):3463-3473
Soil degradation and desertification affect many areas of the planet. One such area is the Mediterranean region of SE Spain, where the climatological and lithological conditions, together with the relief of the landscape and anthropological activity, including agricultural abandonment, are responsible for increasing desertification. It is therefore considered to be of extreme importance to be able to measure soil degradation quantitatively. The aim of this study was to make a microbiological and biochemical characterisation of different soil catenas in SE Spain, including in a wide range of plant cover densities in an attempt to assess the suitability of the parameters measured to reflect the state of soil degradation and the possibility of using the parameters to elaborate a microbiological degradation index (MDI) valid for use in semiarid climates. For this, several indices related with the organic matter content (total organic carbon, TOC, water-soluble carbon, WSC, and water-soluble carbohydrates, WSCh), with the size of microbial populations (microbial biomass carbon, MBC) and related activity (respiration and enzymatic activities) were determined in the soils of three different catenas in different seasons of the year. The values of these parameters were seen to be closely related with the degree of vegetal cover, forest soils with a high cover value showing the highest indices. There was a highly significant positive correlation (p<0.01) between the TOC and WSC content, and other parameters such as MBC, ATP, dehydrogenase activity and the activity of different hydrolases (urease, protease, phosphatase and β-glucosidase). The results show that the parameters analysed are a good reflection of a soil's microbiological quality since the soils with the worst characteristics (saline and with low organic matter and nutrient content) showed the lowest values. The study provides a soil degradation index based on its microbiological properties: MDI. This index is a function of the following five parameters, which showed the greatest weight in the factorial analysis made with all the parameters analysed: dehydrogenase activity, WSCh, urease activity, WSC and respiration. 相似文献
495.
Moreno FJ Molina E Olano A López-Fandiño R 《Journal of agricultural and food chemistry》2003,51(2):394-400
Glucose-lysine model systems prepared over a range of pH values (5-10) in unbuffered and buffered media were incubated at 60 degrees C either under atmospheric pressure or at 400 MPa. The results obtained showed that high pressure affected in different ways the different stages of the Maillard reaction and that such effects were strongly influenced by pressure-induced changes in the pH of the systems. In unbuffered media, at an initial pH < or =8.0, the formation of Amadori rearrangement products (ARP) was not considerably affected by pressure, whereas the intermediate and advanced stages of the Maillard reaction were suppressed, suggesting a retardation of the degradation of the ARP. In buffered media, at pH values < or =8.0, pressure slowed the Maillard reaction from the initial stages. These effects are attributed to the pH drop caused by the pressure-induced dissociation of the acid groups. In unbuffered and buffered media at initial pH = 10.2, high pressure accelerated the formation and subsequent degradation of ARP, leading to increased levels of intermediate and advanced reaction products. 相似文献
496.
M. J. Suso S. Gilsanz G. Duc P. Marget M. T. Moreno 《Genetic Resources and Crop Evolution》2006,53(7):1427-1439
Knowledge of gene flow is essential for designing strategies of germplasm multiplication. Inter and intra-plot gene flow and
pollen dispersion between small plots in a field of Vicia faba germplasm multiplication were measured under four isolation zones at two locations. The four isolation zones were: a barren
zone, a nucleocytoplasmic Vicia faba male sterile line, a Vicia faba tetraploid genotype and a Vicia narbonensis L. population. Genotypes fixed for alternative isozyme and allozyme alleles allowed the identification of inter and intra-plot
hybrids through progeny testing. A set of log-likelihood ratio (LLR) G tests were used to analyze the effects of geographical location, isolation zone and genotype on the different components
of gene flow. Considerable heterogeneity among the genotypes in all the components, inter and intra-plot gene flow and pollen
dispersion, of gene flow has been found. It has been shown that gene flow is location, isolation zone and genotype dependent.
Planting a barrier surrounding the plots rather than using a non cultivated area between plots seemed more or less efficient
for preventing inter-plot gene flow depending on the genotype and the location. Specific associations between genotype and
male sterile or tetraploid border rows for every location can bring about gene flow as high, or even higher, than those produced
by a barren zone. Differences among the genotypes and borders in flowering overlapping appear not to be the major factor influencing
the pattern of gene flow. Implications of the pattern of gene flow observed are discussed in relation to crop diversity managed
by farmers. 相似文献
497.
Nieva Moreno MI Zampini IC Ordóñez RM Jaime GS Vattuone MA Isla MI 《Journal of agricultural and food chemistry》2005,53(23):8957-8962
This study evaluates the toxic, genotoxic/mutagenic, and antimutagenic effects of propolis extract from Amaicha del Valle, Tucumán, Argentina. The cytotoxicity assays carried out with the lethality test of Artemia salina revealed that the LD50 was around 100 microg/mL. Propolis extracts showed no toxicity to Salmonella typhimurium TA98 and TA100 strains and Allium cepa at concentrations that have antibiotic and antioxidant activities. Otherwise, for the testing doses, neither genotoxicity nor mutagenicity was found in any sample. The propolis extracts were able to inhibit the mutagenesis of isoquinoline (IQ) and 4-nitro o-phenylenediamine (NPD) with ID50 values of 40 and 20 microg/plate, respectively. From this result, the studied propolis may be inferred to contain some chemical compounds capable of inhibiting the mutagenicity of direct-acting and indirect-acting mutagens. A compound isolated from Amaicha del Valle propolis, 2',4'-dihydroxychalcone, showed cytotoxic activity (LC50 values of 0.5 microg/mL) but was not genotoxic or mutagenic. Furthermore, this compound was able to inhibit the mutagenicity of IQ (ID50 values of 1 microg/plate) but was unable to inhibit the mutagenicity of NPD. Our results suggest a potential anticarcinogenic activity of Amaicha del Valle propolis and the chalcone isolated from it. 相似文献
498.
499.
Dib A Palma S Suárez G Farías C Cabrera P Castro S Allemandi D Moreno L Lanusse C Sánchez Bruni S 《Journal of veterinary pharmacology and therapeutics》2011,34(2):136-141
Dib, A., Palma, S., Suárez, G., Farías, C., Cabrera, P., Castro, S., Allemandi, D., Moreno, L., Lanusse, C., Sánchez Bruni, S. Albendazole sulphoxide kinetic disposition after treatment with different formulations in dogs. J. vet. Pharmacol. Therap. 34 , 136–141. New therapeutic strategies based on the search of alternative formulations of albendazole (ABZ) and albendazole sulphoxide (ABZSO) are under current development to optimize posology and antiparasite efficacy in dogs. In an incomplete block design, nine dogs were randomly divided into three groups (n = 6). Treatments were carried out in two phases as follows. Phase I: Group I (treatment A), animals received ABZ at 25 mg/kg of conventional formulation. Group II (treatment B), dogs received 25 mg/kg of a modified poloxamer‐ABZ formulation. Group III (treatment C), animals were treated with ABZSO in equimolar amount to ABZ doses. After 21 days of wash‐out period the experiment was repeated (Phase II). Blood samples were collected over 24 h and subsequently analysed by high performance liquid chromatography. ABZSO and ABZSO2 were the analytes recovered in plasma. Significant higher (P < 0.001) ABZSO area under the concentration–time curve (+500%) and Cmax (+487%) values were obtained for the treatment C in comparison with treatments A and B. However, no statistical differences on pharmacokinetic parameters were found between formulations A and B. In conclusion, the enhanced plasma concentration profile obtained for the ABZSO formulation used in treatment C may contribute to optimize the anthelmintic control in dogs. 相似文献
500.
Hoelzer K Cummings KJ Wright EM Rodriguez-Rivera LD Roof SE Switt AI Dumas N Root T Schoonmaker-Bopp DJ Grohn YT Siler JD Warnick LD Hancock DD Davis MA Wiedmann M 《Veterinary microbiology》2011,150(3-4):389-393
Salmonella Cerro prevalence in US dairy cattle has increased significantly during the past decade. Comparison of 237 Salmonella isolates collected from various human and animal sources between 1986 and 2009 using pulsed-field gel electrophoresis, antimicrobial resistance typing, and spvA screening, showed very limited genetic diversity, indicating clonality of this serotype. Improved subtyping methods are clearly needed to analyze the potential emergence of this serotype. Our results thus emphasize the critical importance of population-based pathogen surveillance for the detection and characterization of potentially emerging pathogens, and caution to critically evaluate the adequacy of diagnostic tests for a given study population and diagnostic application. 相似文献