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121.
Three foals aged between 21 and 44 days were presented for evaluation of pyrexia and lameness. Each had subcutaneous abscessation associated with osteomyelitis of a rib at the costochondral junction and pathological fracture of the affected rib; one foal had more than one rib affected. Other localised sites of infection included other sites of osteomyelitis, omphalophlebitis, uveitis, enterocolitis, and calcaneal bursitis. The subcutaneous abscessation and rib osteomyelitis was treated surgically in two foals. Salmonella typhimurium was isolated from the subcutaneous abscess in one foal and from the faeces of another. Two of the three foals were euthanased. Ultrasonography was a more useful modality than radiography for establishing the diagnosis of costal osteomyelitis. 相似文献
122.
Most crop models simulate the crop canopy as an homogeneous medium. This approach enables modelling of mass and energy transfer through relatively simple equations, and is useful for understanding crop production. However, schematisation of an homogeneous medium cannot address the heterogeneous nature of canopies and interactions between plants or plant organs, and errors in calculation of light interception may occur. Moreover, conventional crop models do not describe plant organs before they are visible externally e.g. young leaves of grasses. The conditions during early growth of individual organs are important determinants of final organ size, causing difficulties in incorporating effects of environmental stresses in such models. Limited accuracy in describing temporal source-sink relationships also contributes to difficulty in modelling dry matter distribution and paramaterisation of harvest indices. Functional-architectural modelling aims to overcome these limitations by (i) representing crops as populations of individual plants specified in three dimensions and (ii) by modelling whole plant growth and development from the behaviour of individual organs, based on models of organs such as leaves and internodes. Since individual plants consist of numerous organs, generic models of organ growth applicable across species are desirable. Consequently, we are studying the development of individual organs, and parameterising it in terms of environmental variables and plant characteristics. Models incorporating plant architecture are currently applied in education, using dynamic visual representation for teaching growth and development. In research, the 3D representation of plants addresses issues presented above and new applications including modelling of pesticide distribution, fungal spore dispersal through splashing and plant to plant heterogeneity. 相似文献
123.
花生体细胞胚胎诱导和植株再生研究 总被引:6,自引:2,他引:4
以花生成熟种胚为外植体,在MS附加不同激素(20mg/L2,4-D或5mg/L Picloram)的培养基上黑暗培养,胚性愈伤组织发生率和产胚量无明显差异,在MS+5mg/L Picloram培养基上,胚性愈伤组织发生率和产胚量和品种类型有关,珍珠豆型花生品种胚性愈伤组织发生率和产胚量高于普通型花生品种。体胚在MS+10mg/L BA培养基上苗再生达36.3%-77.8%,再生小苗在MS+0.3m 相似文献
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Del Rio Vilas VJ Ancelet S Abellan JJ Birch CP Richardson S 《Preventive veterinary medicine》2011,98(1):29-38
We describe the application of Bayesian hierarchical models (BHM) to the analysis of risk of sheep scrapie using data from multiple surveillance sources. More specifically, we analysed data from the test results of three surveillance sources on classical and atypical scrapie in Wales for the period 2002-2006. For each form of scrapie, a BHM was fitted to assess the occurrence of spatial patterns of risk shared by the multiple surveillance sources and the association between covariates and disease. We defined a shared-component model whereby the two types of data sources: exhaustive lists (e.g. reports of clinical cases) and sample-based data sources (e.g. abattoir survey) shared a common spatial pattern of risks at parish level. This shared component was adjusted by a risk-gradient parameter that moderated the individual contribution of the datasets. For both forms of scrapie, the risk-gradient was not significantly different indicating that the sensitivity of the two types of dataset was similar for the two diseases. The spatial patterns of the combinations of data sources appeared similar within disease. However, our results suggest that classical and atypical scrapie differ in their spatial patterns and disease determinants. The joint approach permitted inference from all the available evidence and resulted in robust and less biased estimates of risk, particularly for atypical scrapie where the number of observations was very limited. 相似文献
128.
Gavin F. Birch 《Journal of Soils and Sediments》2011,11(1):194-208
Purpose
The objective of the current research was to provide a strategy to remediate stormwater from an old, high-developed catchment dominated (94%) by diffuse sources. Contaminated catchment soils, a dense road network and extensive residential development have resulted in degraded sediments in the receiving basin. Retrofitting stormwater remedial devices in such catchment-estuarine systems is difficult, costly and long term. 相似文献129.
The Nature and Distribution of Metals in Soils of the Sydney Estuary Catchment, Australia 总被引:1,自引:0,他引:1
Gavin F. Birch Matthew Vanderhayden Marco Olmos 《Water, air, and soil pollution》2011,216(1-4):581-604
Total topsoil 50th percentile Cu, Pb and Zn concentrations (n?=?491) in the Sydney estuary catchment were 23 ??g?g?1, 60 ??g?g?1 and 108 ??g?g?1, respectively. Nine percent, 6% and 25% of samples were above soil quality guidelines, respectively and mean enrichment was 14, 35 and 29 times above background, respectively. Soils in the south-eastern region of the catchment exhibited highest metal concentrations. The close relationship between soil metal and road network distributions and outcomes of vehicular emissions modelling, strongly suggested vehicular traffic was the primary source of metals to catchment soils. Catchment soil and road dust probably make an important contribution to contamination of the adjacent estuary. The concentration of soil metals followed the land use trend: industrial?>?urban?>?undeveloped areas. A high proportion (mean 45%, 62% and 42%, for Cu, Pb and Zn, respectively) of metals in the soils may be bioavailable. 相似文献
130.
YASMINDA MALIK DVM DAVID SPRENG DVM Diplomate ECVS & ACVECC MARTIN KONAR DVM Diplomate ECVDI MARCUS G. DOHERR DVM PhD Diplomate ECVPH RE JAGGY PhD Diplomate ECVN JUDITH HOWARD DVM Diplomate ACVIM FRANCK FORTERRE DVM Diplomate ECVS 《Veterinary surgery : VS》2009,38(4):457-462
Objectives— (1) To assess spinal cord blood flow (SCBF) during surgical treatment of disk extrusion in dogs and (2) to investigate associations between SCBF, clinical signs, presurgical MRI images, and 24-hour surgical outcome.
Study Design— Cohort study.
Animals— Chondrodystrophic dogs with thoracolumbar disk extrusion (n=12).
Methods— Diagnosis was based on clinical signs and MRI findings, and confirmed at surgery. Regional SCBF was measured intraoperatively by laser-Doppler flowmetry before, immediately after surgical spinal cord decompression, and after 15 minutes of lavaging the lesion. Care was taken to ensure a standardized surgical procedure to minimize factors that could influence measurement readings.
Results— A significant increase in intraoperative SCBF was found in all dogs (Wilcoxon's signed-rank test; P =.05) immediately after spinal cord decompression and after 15 minutes. Changes in SCBF were not associated with duration of clinical signs; initial or 24-hour neurologic status; or degree of spinal cord compression assessed by MRI.
Conclusion— SCBF increases immediately after spinal cord decompression in dogs with disk herniation; however, increased SCBF was not associated with a diminished 24-hour neurologic status.
Clinical Relevance— An increase in SCBF does not appear to be either associated with the degree of spinal cord compression or of a magnitude sufficient to outweigh the benefit of surgical decompression by resulting in clinically relevant changes in 24-hour outcome. 相似文献
Study Design— Cohort study.
Animals— Chondrodystrophic dogs with thoracolumbar disk extrusion (n=12).
Methods— Diagnosis was based on clinical signs and MRI findings, and confirmed at surgery. Regional SCBF was measured intraoperatively by laser-Doppler flowmetry before, immediately after surgical spinal cord decompression, and after 15 minutes of lavaging the lesion. Care was taken to ensure a standardized surgical procedure to minimize factors that could influence measurement readings.
Results— A significant increase in intraoperative SCBF was found in all dogs (Wilcoxon's signed-rank test; P =.05) immediately after spinal cord decompression and after 15 minutes. Changes in SCBF were not associated with duration of clinical signs; initial or 24-hour neurologic status; or degree of spinal cord compression assessed by MRI.
Conclusion— SCBF increases immediately after spinal cord decompression in dogs with disk herniation; however, increased SCBF was not associated with a diminished 24-hour neurologic status.
Clinical Relevance— An increase in SCBF does not appear to be either associated with the degree of spinal cord compression or of a magnitude sufficient to outweigh the benefit of surgical decompression by resulting in clinically relevant changes in 24-hour outcome. 相似文献