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Objective— To report clinical and diagnostic imaging features, and outcome after surgical treatment of ventral intraspinal cysts in dogs.
Study Design— Retrospective study.
Animals— Dogs (n=7) with ventral intraspinal cysts.
Methods— Clinical signs, magnetic resonance imaging (MRI) findings and surgical findings of 7 dogs and histologic findings (1 dog) with intraspinal cysts associated with the intervertebral disc were reviewed.
Results— Ventral intraspinal cyst is characterized by: (1) clinical signs indistinguishable from those of typical disc herniation; (2) an extradural, round to oval, mass lesion with low T1 and high T2 signal intensity on MRI, compatible with a liquid-containing cyst; (3) cyst is in close proximity to the intervertebral disc; and (4) MRI signs of disc degeneration. Although the exact cause is unknown, underlying minor disc injury may predispose to cyst formation.
Conclusion— Intraspinal cysts have clinical signs identical to those of disc herniation. Given the close proximity of the cyst to the corresponding disc and the similarity of MRI findings to discal cysts in humans, we propose the term "canine discal cyst" to describe this observation.
Clinical Relevance— Discal cysts should be considered in the differential choices for cystic extradural compressing lesions. 相似文献
Study Design— Retrospective study.
Animals— Dogs (n=7) with ventral intraspinal cysts.
Methods— Clinical signs, magnetic resonance imaging (MRI) findings and surgical findings of 7 dogs and histologic findings (1 dog) with intraspinal cysts associated with the intervertebral disc were reviewed.
Results— Ventral intraspinal cyst is characterized by: (1) clinical signs indistinguishable from those of typical disc herniation; (2) an extradural, round to oval, mass lesion with low T1 and high T2 signal intensity on MRI, compatible with a liquid-containing cyst; (3) cyst is in close proximity to the intervertebral disc; and (4) MRI signs of disc degeneration. Although the exact cause is unknown, underlying minor disc injury may predispose to cyst formation.
Conclusion— Intraspinal cysts have clinical signs identical to those of disc herniation. Given the close proximity of the cyst to the corresponding disc and the similarity of MRI findings to discal cysts in humans, we propose the term "canine discal cyst" to describe this observation.
Clinical Relevance— Discal cysts should be considered in the differential choices for cystic extradural compressing lesions. 相似文献
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Benninger MI Seiler GS Robinson LE Ferguson SJ Bonél HM Busato AR Lang J 《American journal of veterinary research》2006,67(1):43-50
OBJECTIVE: To determine the association between the 3-dimensional (3-D) motion pattern of the caudal lumbar and lumbosacral portions of the canine vertebral column and the morphology of vertebrae, facet joints, and intervertebral disks. SAMPLE POPULATION: Vertebral columns of 9 German Shepherd Dogs and 16 dogs of other breeds with similar body weights and body conditions. PROCEDURE: Different morphometric parameters of the vertebral column were assessed by computed tomography (CT) and magnetic resonance imaging. Anatomic conformation and the 3-D motion pattern were compared, and correlation coefficients were calculated. RESULTS: Total range of motion for flexion and extension was mainly associated with the facet joint angle, the facet joint angle difference between levels of the vertebral column in the transverse plane on CT images, disk height, and lever arm length. CONCLUSIONS AND CLINICAL RELEVANCE: Motion is a complex process that is influenced by the entire 3-D conformation of the lumbar portion of the vertebral column. In vivo dynamic measurements of the 3-D motion pattern of the lumbar and lumbosacral portions of the vertebral column will be necessary to further assess biomechanics that could lead to disk degeneration in dogs. 相似文献
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Photolysis on soil surfaces of the organophosphorus insecticides diazinon, methidathion and profenofos was studied under artificial sunlight conditions. All three compounds were readily degraded under the conditions used. The rate of degradation decreased in the order diazinon, profenofos, methidathion and was always greater in moist than in dry soil. The same order of stability was also observed from photolysis studies in aqueous solution. The major photolysis products identified were 2-isopropyl-6-methylpyrimidin-4-ol from diazinon, 5-methoxy-3H-1,3,4-thiadiazol-2-one from methidathion and 4-bromo-2-chlorophenol and 4-bromo-2-chlorophenyl ethyl hydrogen phosphate from profenofos. The same compounds were formed in hydrolysis studies and also upon photodecomposition in aqueous solutions of diazinon and methidathion. Profenofos, however, showed a different photolytic reaction in aqueous systems, forming O-(2-chlorophenyl) O-ethyl S-propyl phosphorothioate. Soil photolysis studies together with hydrolysis experiments could be a useful quick method for obtaining early information on the chemical breakdown products which are to be expected in the soil environment. 相似文献
108.
Piotr Nowicki Vladimir Vrabec Birgit Binzenhöfer Johann Feil Barbara Zakšek Thomas Hovestadt Josef Settele 《Landscape Ecology》2014,29(3):401-412
Metapopulation models typically assume that suitable habitats occupied by local populations and unsuitable matrix separating them form a ‘black-and-white’ landscape mosaic, in which dispersal is primarily determined by the spatial configuration of habitat patches. In reality, however, the matrix composition is also likely to influence dispersal. Using intensive mark-recapture surveys we investigated inter-patch movements in Maculinea (Phengaris) nausithous and M. teleius occurring sympatrically in six metapopulations. Three of these metapopulations had the matrix dominated by forest, an inhospitable environment for grassland butterflies, whereas in the remaining three the matrix was mostly composed of open environments. Dispersal parameters derived with the Virtual Migration model revealed significant differences between both groups of metapopulations. Both species had a lower propensity to emigrate from their natal habitat patches, and they suffered substantially higher dispersal mortality in the metapopulations with forest matrix. On the other hand, mean dispersal distances were roughly an order of magnitude longer in forest matrix as compared with open landscapes (ca. 500–1,500 vs. 100–200 m). Our results suggest that inhospitable forest matrix induces strong selection against dispersal, leading to a reduced emigration rate. At the same time, the selection may promote emigrants with good dispersal abilities, which are able to perform long-distance movements. Thus, while it is generally believed that a matrix structurally similar to the habitat of a species should improve the functional connectivity of habitat patches, our findings imply that this may not necessarily be the case. 相似文献
109.
Minh Luan Nguyen Johann Glaes Stijn Spaepen Bernard Bodson Patrick du Jardin Pierre Delaplace 《植物养料与土壤学杂志》2019,182(3):325-334
Bacillus velezensis strains, belonging to plant growth‐promoting rhizobacteria (PGPR), are increasingly used as microbial biostimulant. However, their field application to winter wheat under temperate climate remains poorly documented. Therefore, three B. velezensis strains IT45, FZB24 and FZB42 were tested for their efficacy under these conditions. Two biological interaction systems were firstly developed under gnotobiotic and greenhouse conditions combined with sterile or non‐sterile soil, respectively, and finally assayed in the field during two years coupled with different N fertilization rates. Under gnotobiotic conditions, all three strains significantly increased root growth of 14 d‐old spring and winter wheat seedlings. In the greenhouse using non‐sterile soil, only FZB24 significantly increased root biomass of spring wheat (+31%). The three strains were able to improve nutrient uptake of the spring wheat grown in the greenhouse, particularly for the micronutrients Fe, Mn, Zn, and Cu, but the observed increases in nutrient uptake were dependent on the organs and the elements. The root biomass increases in inoculated plants coincided with lowered nutrient concentrations of P and K. In 2014, under field conditions and absence of any N fertilizer supply, FZB24 significantly increased grain yields by 983 kg ha?1, or 14.9%, in relation to non‐inoculated controls. The three strains in the 2015 field trial failed to confirm the previous positive results, likely due to the low temperatures occurring during and after inoculations. The Zeleny sedimentation value, indicative of flour quality, was unaffected by the inoculants. The results are discussed in the perspective of bacterial application to wheat under temperate agricultural practices. 相似文献
110.
对蛋氨酸添加剂生物学效价的研究 总被引:1,自引:0,他引:1
蛋氨酸添加剂有两种:蛋氨酸和蛋氨酸羟基类似物(DL-MethionineHydroxyAnalogue-FreeAcid,MHA-FA)。从MHA-FA分子结构看,α位碳原子上为羟基而非氨基,故MHA-FA不是蛋氨酸。MHA-FA在动物体内须经转氨酶的作用才能形成蛋氨酸。不论蛋氨酸还是蛋氨酸羟基类似物,两者都有液体和固体产品,目前市场上常见的是固体蛋氨酸和液体蛋氨酸羟基类似物。固体蛋氨酸含99%的蛋氨酸,液体MHA-FA含88%的羟基类似物,其中包括65%的单体和23%的二聚体和多聚体羟基类似物。目前对液体MHA-FA的生物… 相似文献