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31.
32.
Egyptian geese (Alopochen aegypticus), a duck species endemic to sub-Saharan Africa and occasionally implicated in the transmission of avian influenza viruses (AIV) to farmed ostriches, were experimentally infected with low pathogenicity H7N1 and H6N8 viruses to assess viral shedding and immune profiles. Following the first infection with H7N1 virus, high titers of virus were shed from both the tracheae and cloacae for at least 7 days postinfection, and tracheal shedding lasting until day 14. All detectable shedding from both tracheae and cloacae had ceased within 28 days of infection. Antibody titers peaked at day 7 postinfection, but the initial immune response was short-lived. Birds that received a second challenge with the homologous H7N1 virus mounted a more robust response that lasted beyond 66 days postchallenge, and H7N1 virus was detected, albeit at much lower levels, until day 28 post secondary infection (psi) in the cloaca and beyond day 28 psi in the trachea. Birds that received an initial infection with H7N1 virus were also challenged with H6N8 virus, and because a comparable shedding pattern to the H7N1 challenge group was observed, we concluded that the effect of any nonspecific immunity was negligible. 相似文献
33.
Davenport-Goodall CL Boston RC Richardson DW 《American journal of veterinary research》2004,65(2):238-244
OBJECTIVE: To investigate the effects of insulin-like growth factor-II (IGF-II) on DNA and glycosaminoglycan (GAG) synthesis and the expression of matrix-related genes in equine articular cartilage explants and chondrocytes, respectively, with and without interleukin 1-beta (IL1-beta). SAMPLE POPULATION: Articular cartilage from 12 adult horses. PROCEDURE: Articular cartilage was incubated in standard media with and without equine IL1-beta (10 ng/mL) containing various concentrations of IGF-II for 72 hours. Synthesis of DNA and GAG was determined by incorporation of thymidine labeled with radioactive hydrogen (3H) and sulfate labeled with radioactive sulfur (35S), respectively. Total GAG content of the explants and spent media was determined by use of the 1,9-dimethylmethylene blue assay. Northern blots of RNA from cultured equine articular cartilage chondrocytes were hybridized with cDNA of major matrix molecules. RESULTS: Insulin-like growth factor-II stimulated DNA and GAG synthesis at concentrations of 25 and 50 ng/mL, respectively. In cartilage explants conditioned with IL1-beta, IGF-II stimulated DNA and GAG synthesis at concentrations of 500 and 50 ng/mL, respectively. Insulin-like growth factor-II had no effect on total GAG content as determined by the 1,9-dimethylmethylene blue assay. No specific effects on steady-state levels of messenger RNAs were observed. CONCLUSIONS AND CLINICAL RELEVANCE: Insulin-like growth factor-II stimulated DNA and GAG synthesis in equine adult cartilage and may have potential application in vivo. 相似文献
34.
AORTO-CARDIAC FISTULAS IN SEVEN HORSES 总被引:1,自引:0,他引:1
Celia M. Marr BVMS MVM PhD MRCVS Virginia B. Reef DVM T.J. Brazil BVSc Cert. EM MRCVS W.P. Thomas DVM D.C. Knottenbelt BVM&S DVM&S MRCVS D.F. Kelly BVSc MA FRCPath MRCVS J.R. BAKER BVSc Ph D MRCVS Johanna M. Reimer VMD Abby D. Maxson VMD J.S. Crowhurst BA B Vet Med MRCVS 《Veterinary radiology & ultrasound》1998,39(1):22-31
This report describes the history, clinical, electrocardiographic and echocardiographic findings, treatment, outcome, and post-mortem findings in seven horses with aorto-cardiac fistula. Affected horses included 5 stallions, one gelding and one mare; 2 each of the Thoroughbred, Arabian and Standardbred breeds and one Thoroughbred-cross with a mean ± s.d. age of 12 ± 4 years, range 6–18 years. The presenting sings were acute distress (four horses), exercise intolerance (two horses) and the lesion was detected during a routine examination in one horse. Five horses had monomorphic ventricular tachycardia on admission and one other had a history of this arrhythmia. Five horses had a characteristic continuous murmur loudes in the right fourth intercostal space. Echocardiography (six horuses) and/or post-mortem examination (four horses) revealed the horses had aorto-cardiac fistulas arising from the right aortic sinus in all five horses in which the site was recorded. Two horses had ruptured aneurysmall dilatations of the aortic wall at this site. Fistulas extended into the right ventricle in four horses; the right atrium in two horses, the left ventricle in one horse, and five horses had dissecting tracts in the septal myocardium. Horses survived for periods ranging from 24th to 4 years. Aorto-cardiac fistula should be considered in the differential diagnosis for horses presenting with acute distress, bounding arterial pulse, a right-sided continuous murmur and/or monomorphic ventricular tachycardia, particularly in middle-aged or older stallions. Echocardiography is the technique of choice for confirming the diagnosis and demonstrating accompanying cardiac changes. 相似文献
35.
Suarez Luz Angelica Robson Andrew McPhee John O’Halloran Julie van Sprang Celia 《Precision Agriculture》2020,21(6):1304-1326
Precision Agriculture - Proximal and remote sensors have proved their effectiveness for the estimation of several biophysical and biochemical variables, including yield, in many different crops.... 相似文献
36.
Celia Abolnik Christine Strydom Debbie Landman Rene Pieterse 《Journal of veterinary diagnostic investigation》2021,33(6):1089
Avian influenza surveillance is a requirement for commercial trade in ostrich products, but influenza A viruses (IAVs) have proven difficult to isolate from ostrich tracheal swabs that test positive using molecular methods. We hypothesized that microbes unique to the ostrich trachea propagate in the transport medium after sampling and affect viral viability. We cultured tracheal swabs from 50 ostriches on 4 farms in South Africa, and recovered and identified 13 bacterial, 1 yeast, and 2 fungal species. Dietzia sp. had not been identified previously in the oropharyngeal tract of a bird, to our knowledge. The bacteria were tested for antimicrobial susceptibility, and most aerobic species, except for Streptococcus sp. and Pseudomonas sp., were sensitive to enrofloxacin; all were susceptible to sulfonamide. Virus inhibition experiments determined that ostrich-source Streptococcus sp., Pantoea sp., and Citrobacter freundii produced extracellular metabolites that caused a substantial reduction in the IAV titers of 99.9%. Streptomyces, Corynebacterium, Staphylococcus, Arthrobacter gandavensis, Pseudomonas putida, and Acinetobacter spp. similarly reduced the viability of IAV from 77.6% to 24.1%. Dietzia appeared to have no effect, but Rothia dentocariosa, Rhodotorula spp., and Clostridium spp. slightly increased the viability of IAV by 25.9, 34.9, and 58.5%, respectively. 相似文献
37.
With the expectation of adverse climate change impacts, some (often majority) Indigenous populations of the Pacific are expressing a preference to remain on Indigenous lands for cultural and spiritual reasons. In some cases, Indigenous people express preparedness to die on traditional territory rather than relocate, representing a new type of agency and resistance to dispossession. This is a prominent politics of place of relevance to emerging debates and decision‐making around retreat and relocation. If climate change is experienced by populations as an existential threat to culture, identity and place‐based connections, voluntary immobility can be an important adaptation strategy that helps to strengthen cultural and spiritual resilience among those facing the prospect of a lost homeland. This paper argues that voluntary immobility decisions need ethically robust and culturally appropriate policies and practices, particularly when a site is deemed by external experts to be no longer fit for human settlement. National governments, civil society groups, international organisations and donors will need to: engage in culturally meaningful dialogue with communities about relocation and immobility; respect, protect and fulfil the rights of ‘immobile’ people and those on the move; and confirm that in situ adaptation options have been exhausted. 相似文献
38.
Guillem Segarra Eva Casanova Celia Borrero Manuel Avilés Isabel Trillas 《European journal of plant pathology / European Foundation for Plant Pathology》2007,117(4):393-402
The incidence/severity of soil-borne plant diseases is often reduced when composts are used as growth media. However, much
less information is available about the effects of composts on the development of foliar diseases. Here we studied the suppressive
capacity of five composts (from olive marc-cotton gin trash, grape marc, cork, spent mushroom and municipal organic and yard
wastes) as growth media against Botrytis cinerea disease in cucumber plants. We also examined the putative correlations of several biotic and abiotic factors involved in
disease suppression. The suppressive capacity of the growth media was studied by comparing disease incidence/severity in plants
grown in composts with that occurring in plants grown in commercial peats, which are conducive to most soilborne diseases.
Correlations were made between the occurrence of disease and leaf nutrient status, as well as electrical conductivity (EC)
and microbial activity (measured as β-glucosidase activity) in the growth media. Cucumber plants grown in the peats showed
greater severity of B. cinerea during the bioassay than those grown in composts. Mo, Ca and Si content in leaves showed negative correlations with this
disease. A negative correlation with disease severity was observed for EC and microbial activity in the growth media. The
noticeable reduction in B. cinerea in plants grown in composts was related to the supply of specific chemical elements, a certain degree of salt stress, and
the high microbial activity of composts. 相似文献
39.
Marcelo Carvalho Santos Chiara Milani Paolo Zucchini Celia Raquel Quirino Stefano Romagnoli Isabel Candia Nunes da Cunha 《Reproduction in domestic animals》2021,56(3):476-483
The administration of fish oils is known to cause changes in several reproductive parameters of domestic animals. The ingestion of polyunsaturated fatty acids (PUFAs) of the omega-3 family, such as docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), has been described and correlated with changes in the semen quality, testosterone levels and male fertility. Nevertheless, few studies monitored and registered effects after ceasing supplementation. In the present study, we monitored the Doppler velocimetric and ultrasonographic parameters of nine dogs' testis for 90 days (D90) checking the effect of salmon oil supplementation, and monitoring continued for 60 days more, after ceasing supplementation (D150). Ultrasonographic evaluations comprised determining the Doppler velocimetric parameters, testicular and epididymal volume, and testicular echotexture. Peak systolic velocity (PSV) as well as final diastolic velocity (EDV) in the supratesticular arteries (STA), and marginal artery (MA) increased during the period of treatment and kept that level up to D150. There was no difference between the fish-oil supplementation period and the unsupplemented one regarding the testicular and epididymal volume and echogenicity and heterogeneity characteristics. A negative correlation was found between heterogeneity of testis and sperm production (r = −.41, p = .008). Doppler velocimetry indices were affected by the supplementation, leading to an increase in testicular blood flow. 相似文献
40.
Morillo E Undabeytia T Cabrera A Villaverde J Maqueda C 《Journal of agricultural and food chemistry》2004,52(4):884-890
Adsorption-desorption studies of norflurazon on 17 soils of very different characteristics have been performed using a batch equilibration method and correlated to its mobility, activity, and persistence in soils. The influence of different soil properties and components on norflurazon adsorption was determined. The significant variables were organic matter (OM) content and iron and aluminum oxides, which accounted for 85 and 11% of the variability, respectively. Norflurazon desorption from soils was hysteretic in all cases, being more irreversible at the lowest herbicide concentrations adsorbed. The percentage of norflurazon eluted from columns of selected soils reached almost 100% in soils with sand content >80% and OM <1%, but in the soil which gave the highest sorption, herbicide residues were not detected at depths >16 cm. The herbicidal activity of norflurazon was followed by measuring its bleaching effect on soybean plants, and the herbicide concentration required to give 50% chlorophyll inhibition (CI(50)) was calculated. CI(50) was achieved on a sandy soil with 0.08 mg x kg(-)(1), whereas 1.98 mg x kg(-)(1) was necessary for the soil that presented maximum norflurazon adsorption. 相似文献