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71.
Marcelo Mieres Marcelo A. Gómez Carla Lillo Marcela A. Rojas Manuel Moroni Pamela Muñoz Gerardo Acosta‐Jamett Ricardo Wiegand 《Veterinary radiology & ultrasound》2013,54(3):237-244
Gurltia paralysans is a rare metastrongylid nematode of domestic cats that is found mainly in the veins of the spinal cord subarachnoid space and parenchyma. Endemic regions for G. paralysans mainly include Chile and Argentina. The ante mortem diagnosis of gurltiosis is difficult and based primarily on neurological signs, epidemiological factors, and the exclusion of other causes of feline myelopathies. The purpose of this retrospective case series was to describe clinical, imaging, and pathologic characteristics in nine domestic cats naturally infected with G. paralysans. Imaging tests included radiography, myelography, computed tomographic myelography (myelo‐CT), and magnetic resonance imaging (MRI). Neurological signs included paraparesis, paraplegia, pelvic limb ataxia and proprioceptive deficits, pelvic limb tremors, lumbosacral hyperesthesia, and tail trembling or atony. Complete blood count findings included a decrease in the mean corpuscular hemoglobin concentration value in eight cats. Eosinophilia in peripheral blood was observed in three cats, and thrombocytopenia was observed in three cats. Cerebrospinal fluid analysis revealed mononuclear pleocytosis in five cases. Myelo‐CT showed diffuse enlargement of the spinal cord at the midthoracic, lumbar, and sacral regions in all cats. Magnetic resonance image findings in the thoracic and lumbar region demonstrated multiple small nodular areas of T2 hyperintensity in the periphery of the spinal cord parenchyma. Localized intraparenchymal areas of increased T2 intensity were also observed in the thoracolumbar spinal cord and lumbosacral conus medullaris. In conclusion, G. paralysans should be considered as a differential diagnosis for domestic cats in endemic regions that have this combination of clinical and imaging characteristics. 相似文献
72.
Alejandro Solla Lorena García Andrea Pérez Ana Cordero Elena Cubera Gerardo Moreno 《Phytoparasitica》2009,37(4):303-316
The Iberian forests are suffering severe disease and mortality as a result of decline, with Quercus ilex the major species at risk. Trunk injections with potassium phosphonate, which have been used successfully to control Phytophthora cinnamomi, were tested against decline. In an area in which P. cinnamomi was isolated, Q. ilex trees showing different degrees of decline were trunk-injected. Soil properties, and measurements of soil water content (θ)
and depth to soil water table were assessed at three sites with markedly different decline incidences. Over the 5 years following
the initiation of the experiment, mean symptoms among spring-treated trees and autumn-treated trees, or among trees injected
twice a year (spring and autumn), once a year, and non-injected, were not significantly different. No effects of the treatments
on shoot growth and acorn production were observed. However, θ values under trees which recovered from decline were higher
than θ values under trees which did not recover from decline. At the site with the highest incidence of decline and tree mortality,
P. cinnamomi was rarely isolated, and the presence of gravel, soil infiltration capacities and water table depth values were significantly
higher than at the other sites, water stress being more likely to contribute to decline than P. cinnamomi. In areas in which θ is low, the distribution of phosphonate on the tree would be limited. Since the thresholds for phytotoxicity
of potassium phosphonate in Q. ilex trees at the site studied would be higher than the amounts used, rates of the chemical slightly less than those that cause
phytotoxicity should be tested. 相似文献
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76.
Brownlee D Tsou P Aléon J Alexander CM Araki T Bajt S Baratta GA Bastien R Bland P Bleuet P Borg J Bradley JP Brearley A Brenker F Brennan S Bridges JC Browning ND Brucato JR Bullock E Burchell MJ Busemann H Butterworth A Chaussidon M Cheuvront A Chi M Cintala MJ Clark BC Clemett SJ Cody G Colangeli L Cooper G Cordier P Daghlian C Dai Z D'Hendecourt L Djouadi Z Dominguez G Duxbury T Dworkin JP Ebel DS Economou TE Fakra S Fairey SA Fallon S Ferrini G Ferroir T Fleckenstein H Floss C Flynn G 《Science (New York, N.Y.)》2006,314(5806):1711-1716
The Stardust spacecraft collected thousands of particles from comet 81P/Wild 2 and returned them to Earth for laboratory study. The preliminary examination of these samples shows that the nonvolatile portion of the comet is an unequilibrated assortment of materials that have both presolar and solar system origin. The comet contains an abundance of silicate grains that are much larger than predictions of interstellar grain models, and many of these are high-temperature minerals that appear to have formed in the inner regions of the solar nebula. Their presence in a comet proves that the formation of the solar system included mixing on the grandest scales. 相似文献
77.
Characterization of a Potential Nutraceutical Ingredient: Pomegranate (Punica granatum L.) Seed Oil Unsaponifiable Fraction 总被引:1,自引:1,他引:0
Augusta Caligiani Francesca Bonzanini Gerardo Palla Martina Cirlini Renato Bruni 《Plant foods for human nutrition (Dordrecht, Netherlands)》2010,65(3):277-283
The chemical fingerprinting of the unsaponifiable fraction of different Punica granatum seed oils was performed in order to evaluate their potential as a functional food ingredient. Qualitative and quantitative
determinations of tocopherol, aliphatic alcohol (including policosanol), squalene, phytosterols and triterpene contents were
performed by GC-MS. A high yield (3.1–4.2%) of unsaponifiable matter was obtained and consistent levels of squalene (up to
800 mg/kg) and policosanol (118–185 mg/kg) were noticed. β-sitosterol (up to 8069 mg/kg) and cycloartenol (5916–7766 mg/kg)
were predominant in phytosterol and triterpene fractions, while β- and δ-tocopherol were the most abundant vitamin E forms.
Some minor variations were noticed between samples. From the results obtained, it can be suggested that the seed oil of P. granatum can be considered an interesting alimentary source of substances of nutraceutical value involved in the modulation of cholesterol
metabolism. 相似文献
78.
José Martínez-Calvo Ana Delia Gisbert M. Carmen Alamar Rosa Hernandorena Carlos Romero Gerardo Llácer María L. Badenes 《Genetic Resources and Crop Evolution》2008,55(5):695-703
Loquat species (Eriobotrya japonica Lindl.) originated in China, later was introduced in Japan. However, introduction in Europe occurred much later, in 18th
century, it was introduced as an ornamental tree. Since then, the species was very well adapted to the Mediterranean climate,
mainly in South East of Spain, where is located more than 50% of total European crop production. A European Project titled
‘Conservation, evaluation and collection of underutilized fruit species’ supported surveys and collection of plant material
from these species in the Mediterranean basin countries. One of these surveys resulted in a germplasm collection of loquat
established at IVIA, Valencia, Spain. This collection is being extended with new accessions collected across the world, currently
the collection have 123 accessions under study. Germplasm management needs first a characterization of the plant material
introduced and second diversity studies into the collection that could point out the variability pattern, to establish groups
of accessions with similar traits and the most significant variables. These results allow organizing the information gathered
for further uses. In this paper, 62 accessions from the IVIA germplasm collection were studied. Results from 43 variables
were gathered and data studied by multivariate analysis. The analysis allowed summarizing the data tables with new variables
containing most of the information. These results along with those obtained in the coming years will allow define a nuclear
collection (minimum number of accessions that contained all the variability present in the collection). 相似文献
79.
Effect of light limitation on the water quality,bacterial counts and performance of Litopenaeus vannamei postlarvae reared with biofloc at low salinity
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Héctor M Esparza‐Leal Ely S López‐Álvarez Jesús T Ponce‐Palafox Josué A Melendrez‐Soto Marco A Medina‐Astorga Antonio Luna‐González Wenceslao Valenzuela‐Quiñónez Píndaro Álvarez‐Ruiz Gerardo Rodríguez‐Quiroz 《Aquaculture Research》2017,48(8):4371-4379
The aim of this study was to evaluate the effect of light limitation on the water quality, bacterial counts and performance of Litopenaeus vannamei postlarvae reared with biofloc at low salinity (≈9 g L?1). Two treatments were designed: T1 = culture with natural sunlight and T2 = culture in darkness. After 28 days, in both treatments, the final weight of shrimp was over 0.6 g with a specific growth rate over 7.4% d?1, and a survival rate over 70%. In both treatments, Vibrio sp. concentration presented low values (culture with natural sunlight = 0.1 to 9.9 × 102 CFU mL?1, culture in darkness = 0.4 to 11.7 × 102 CFU mL?1) and Bacillus sp. had high values (culture with natural sunlight = 0.7 to 66.0 × 104 CFU mL?1, culture in darkness = 0.7 to 65.8 × 104 CFU mL?1). All water quality parameters remained within the ranges suitable for shrimp culture, except for alkalinity during the first stage of the study. Although in some sampling periods some significant differences were found in bacterial counts and water quality parameters, shrimp productive performance under culture with biofloc at low salinity was not affected significantly by light limitation. 相似文献
80.
Predicting the distribution of harmful species and their natural enemies in agricultural,livestock and forestry systems: an overview 总被引:1,自引:0,他引:1
AbstractPredicting the potential distribution of harmful species to agriculture, livestock and forestry is decisive to prevent their impacts, especially when these are expanding their range due to global change. Recent advances in species distribution modelling (SDM) have made these tools widely used for biosecurity studies. We reviewed the available literature of SDM for pest, weeds, pathogen species and biological-control agents, with the aims of synthesizing and quantifying the available information, and identifying gaps in the knowledge and future perspectives. SDMs for 420 species were collected from 220 publications. Insect pests were the most frequently studied organisms. CLIMEX and MaxEnt were the most commonly used modelling tools, while pure mechanistic approaches were rarely applied. Most studies covered broad scales, and focused on predicting the distribution of invasive species and/or the effects of climate change. The challenge remains for models to include disturbance, resource availability, and biotic factors, as well as to better quantify uncertainty. This future directions will be fundamental to improve the predictive power of SDMs for productive systems in the context of a rapidly changing World. 相似文献