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141.
Mihiretu Cherinet Hundayehu ;Elsa Du Toit ;Sunette Laurie ;Martin Steyn ;Ria Greyling ;Nokuthula Myeza 《农业科学与技术》2014,(10):811-821
The aim of this study was to assess the effect of long-term in vitro sub-culturing on the varietal degeneration of three sweet potato varieties, namely, Monate, Mokone and Ndou which were sub-cultured for 32, 23 and 12 generations, respectively. Each generation was cultured in a media which is made from 4.43 g/L Murashige and Skoog (MS), 30 g/L sucrose and 2 g/L gelrite, respectively, and grown under 16 h light and 8 h dark photoperiod for 30 d. For each generation, 45 plantlets were acclimatized for two months in a glasshouse. Data on in vitro growth performance and 11 morphological characteristics during acclimatization were recorded. Early root and shoot formation was observed after the 27th and 21st sub-cultured generations of Monate and Mokone, respectively. During acclimatization, plantlets from the same variety showed differences in morphological traits such as leaf colour, abaxial leaf pigmentation, vine pigmentation, petiole pigmentation, leaf wrinkling and flowering. However, the rate of these morphological differences is random and irrespective to increase in sub-culturing. Therefore, to understand the genetic base of these morphological variability, two plantlets from each variety were subjected to genetic analysis by using five simple sequence repeat (SSR) primers (IB-242, IB-318, IB-255F, 1B-248 and IB-255). Although SSR loci IB-255F and IB-318 could distinguish between the three varieties, there were no allelic polymorphisms detected in plantlets from the same varieties. Therefore, long-term sub-culturing do not leads to quality degeneration in the three sweet potato varieties. 相似文献
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143.
Maria Luz Prieto Laurie O’Sullivan Shiau Pin Tan Peter McLoughlin Helen Hughes Montserrat Gutierrez Jonathan A. Lane Rita M. Hickey Peadar G. Lawlor Gillian E. Gardiner 《Marine drugs》2014,12(5):2422-2445
Six antimicrobial-producing seaweed-derived Bacillus strains were evaluated in vitro as animal probiotics, in comparison to two Bacillus from an EU-authorized animal probiotic product. Antimicrobial activity was demonstrated on solid media against porcine Salmonella and E. coli. The marine isolates were most active against the latter, had better activity than the commercial probiotics and Bacillus pumilus WIT 588 also reduced E. coli counts in broth. All of the marine Bacillus tolerated physiological concentrations of bile, with some as tolerant as one of the probiotics. Spore counts for all isolates remained almost constant during incubation in simulated gastric and ileum juices. All of the marine Bacillus grew anaerobically and the spores of all except one isolate germinated under anaerobic conditions. All were sensitive to a panel of antibiotics and none harbored Bacillus enterotoxin genes but all, except B. pumilus WIT 588, showed some degree of β-hemolysis. However, trypan blue dye exclusion and xCELLigence assays demonstrated a lack of toxicity in comparison to two pathogens; in fact, the commercial probiotics appeared more cytotoxic than the majority of the marine Bacillus. Overall, some of the marine-derived Bacillus, in particular B. pumilus WIT 588, demonstrate potential for use as livestock probiotics. 相似文献
144.
Carolyn R. Reider Wendy R. Herdman Laurie E. Drinkwater Rhonda Janke 《Compost science & utilization》2013,21(4):328-339
Composts made from rural and urban residues are increasingly available. Farmers wishing to use these materials need to know how they will perform as crop nutrient sources. The objectives of this field experiment were to evaluate compost as an N source, and to track the effects of compost application on NPK budgets. Four composts of various feedstocks, maturity, and nutrient content were compared to raw dairy manure (RDM) and conventional mineral fertilizer (CNV). A 3-year rotation of corn (Zea mays L.), bell pepper (Capsicum annum), and small grain was established, with all crops present every year. Treatments were applied on an N-equivalent basis, using a 40% availability factor for compost and 50% for RDM. Yields from compost-amended corn were comparable to RDM and CNV by the second year. Pepper, a less N-demanding crop, had no significant yield differences among treatments for the three years. The manure-based compost treatments had the highest P and K surplus after three years, showing that loading levels of these nutrients need consideration when using compost to satisfy crop N needs. Rotations can be designed to extract more P and K, but more practical for the long-term would be reducing compost additions and substituting an additional N source such as a legume. 相似文献
145.
Lynn M. Pezzanite Dean A. Hendrickson Steven Dow Jason Stoneback Lyndah Chow Danielle Krause Laurie Goodrich 《Equine veterinary journal》2022,54(1):24-38
Antibiotics have been injected intra-articularly by equine veterinarians for decades, either prophylactically when other drugs are administered for osteoarthritis or therapeutically to treat septic arthritis. This route of administration has also more recently gained attention in human orthopaedic clinical practice, particularly as an alternative to systemic antibiotic administration to treat infections following prosthetic arthroplasty. While the rationale for injecting antibiotics intra-articularly has been largely focused on achieving high local drug concentrations, there has been relatively little focus on pharmacokinetic parameters of antibiotics administered by this route, or on the potential for local toxicity. The increasing incidence of antibiotic resistance in veterinary and human medicine prompts reconsideration of off-label antibiotic usage and evaluation of evidence-based dosing strategies. The purpose of this review was to summarise the current literature describing intra-articular antibiotic usage, including specific studies where pharmacokinetics, potential safety and toxicity have been evaluated. This review will advance practitioners’ understanding of the use of intra-articularly administered antibiotics, including the overall pros and cons of the approach. 相似文献
146.
Comparative mapping and its use for the genetic analysis of agronomic characters in wheat 总被引:1,自引:0,他引:1
Summary The advent of molecular marker systems has made it possible to develop comparative genetic maps of the genomes of related species in the Triticeae. These maps are being applied to locate and evaluate allelic and homoeoallelic variation for major genes and quantitative trait loci within wheat, and to establish the pleiotropic effects of genes. Additionally, the known locations of genes in related species can direct searches for homoeologous variation in wheat and thus facilitate the identification of new genes. Examples of such analyses include the validation of the effects of Vrn1 on chromosome 5A on flowering time in different crosses within wheat; the indication of pleiotropic effects for stress responses by the Fr1 locus on chromosome 5A; the detection of homoeologous variation for protein content on the homoeologous Group 5 chromosomes; and the detection of a new photoperiod response gene Ppd-H1 in barley from homoeology with Ppd2 of wheat. 相似文献
147.
The 1990s represented a decade of immense changes in environmental management in New Zealand. This paper outlines the challenges of implementing the widespread reforms started in the 1980s. In terms of the environment, reforms came in the form of a large volume of new legislation and a new system of decentralised planning and management. This paper discusses these changes in the context of a shift toward a new environmental paradigm. Key issues and initiatives of the 1990s are discussed which address sustainability, integration, environmental leadership, and public involvement. Specific strategies are outlined in reference to biodiversity, which has been identified as New Zealand's most pervasive environmental issue. Ongoing challenges for the future include how to better involve stakeholders to incorporate alternative values in decision making. 相似文献
148.
Franke AA Cooney RV Henning SM Custer LJ 《Journal of agricultural and food chemistry》2005,53(13):5170-5178
Seven healthy females and six males consumed daily 256 mg of vitamin C, 271 mg of flavanones (mainly as glycosides), 6 mg of carotenoids (mainly xanthophylls and cryptoxanthins), and 0.16 mg of folate by incorporation of daily three times 236 mL of not from concentrate orange juice (OJ) into their habitual diet. At the end of 3 weeks, mean vitamin C, folate, carotenoid, and flavanone plasma concentrations increased significantly relative to baseline by 59% (p < 0.001), 46% (p = 0.018), and 22% (p < 0.001), and 8-fold (p = 0.045), respectively. Flavanones were excreted in urine 9-fold more at the end of the intervention (p = 0.01) but returned to baseline 2 days after study completion. After the 3 week intervention, plasma concentrations of vitamins A and E did not change. 8-Hydroxydeoxyguanosine in white blood cells declined by 16% (p = 0.38; n = 11), and in individuals with high baseline concentrations by 29% (p = 0.36; n = 7), respectively. Low-density lipoprotein (LDL)-/high-density lipoprotein (HDL)-cholesterol ratios decreased but cholesterol (HDL, LDL, total) and thiobarbituric acid reactive substance plasma concentrations did not change significantly. We conclude from this pilot study that OJ is an excellent food source to enhance circulating concentrations of valuable hydrophilic as well as lipophilic phytochemicals. 相似文献
149.
150.
J E Collins D A Benfield W T Christianson L Harris J C Hennings D P Shaw S M Goyal S McCullough R B Morrison H S Joo 《Journal of veterinary diagnostic investigation》1992,4(2):117-126
A recent epizootic of swine infertility and respiratory syndrome (SIRS) in a Minnesota swine herd was investigated. Examination of a sow, neonatal piglets, and stillborn fetuses obtained during the epizootic from the affected herd revealed interstitial pneumonitis, lymphomononuclear encephalitis, and lymphomononuclear myocarditis in the piglets and focal vasculitis in the brain of the sow. Fetuses did not have microscopic lesions. No cause for the infertility and respiratory syndrome was determined. Therefore, attempts were made to experimentally reproduce the disease. Eleven 3-day-old gnotobiotic piglets exposed intranasally to tissue homogenates of piglets from the epizootic became inappetent and febrile by 2-4 days postexposure and had interstitial pneumonitis and encephalitis similar to that seen in the field outbreak. After 2 blind passages in gnotobiotic piglets, tissue homogenates were cultured on continuous cell line CL2621, and a cytopathic virus (ATCC VR-2332), provisionally named SIRS virus, was isolated. Gnotobiotic piglets exposed intranasally to the SIRS virus developed clinical signs and microscopic lesions that were the same as those in piglets exposed to the tissue homogenates, and the virus was reisolated from their lungs. This is the first isolate of SIRS virus in the United States that fulfills Koch's postulates in producing the respiratory form of the disease in gnotobiotic piglets and the first report of isolation and propagation of the virus on a continuous cell line (CL2621). The virus is designated as American Type Culture Collection VR-2332. 相似文献