全文获取类型
收费全文 | 203篇 |
免费 | 14篇 |
专业分类
林业 | 19篇 |
农学 | 5篇 |
基础科学 | 3篇 |
73篇 | |
综合类 | 7篇 |
农作物 | 4篇 |
水产渔业 | 24篇 |
畜牧兽医 | 62篇 |
园艺 | 2篇 |
植物保护 | 18篇 |
出版年
2023年 | 2篇 |
2022年 | 4篇 |
2021年 | 4篇 |
2020年 | 6篇 |
2019年 | 7篇 |
2018年 | 9篇 |
2017年 | 6篇 |
2016年 | 14篇 |
2015年 | 6篇 |
2014年 | 10篇 |
2013年 | 17篇 |
2012年 | 12篇 |
2011年 | 15篇 |
2010年 | 7篇 |
2009年 | 10篇 |
2008年 | 8篇 |
2007年 | 17篇 |
2006年 | 8篇 |
2005年 | 10篇 |
2004年 | 6篇 |
2003年 | 5篇 |
2002年 | 3篇 |
2001年 | 5篇 |
2000年 | 8篇 |
1999年 | 2篇 |
1995年 | 1篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1985年 | 1篇 |
1984年 | 2篇 |
1983年 | 1篇 |
1979年 | 2篇 |
1978年 | 1篇 |
1977年 | 2篇 |
1975年 | 1篇 |
1969年 | 1篇 |
1967年 | 1篇 |
1955年 | 1篇 |
排序方式: 共有217条查询结果,搜索用时 31 毫秒
101.
Cibanal Irene Laura Fernández Leticia Andrea Rodriguez Silvana Andrea Pellegrini Cecilia Noemí Gallez Liliana María 《European journal of plant pathology / European Foundation for Plant Pathology》2022,164(1):33-43
European Journal of Plant Pathology - In this study, propolis extract (EPE) and oregano essential oil (OEO), both natural products with different bioactive compounds, were evaluated in vitro and in... 相似文献
102.
Temperini Carolina Virginia Tudela Marisa Andrea Aluminé Gimenez Gustavo Nestor Di Masi Susana Noemí Pardo Alejandro Guillermo Pose Graciela Noemí 《European journal of plant pathology / European Foundation for Plant Pathology》2022,163(3):529-544
European Journal of Plant Pathology - Recently, a new plant disease was detected in the rural area of the High Valley of Río Negro, in Northern Patagonia, Argentina, called “Brown Spot... 相似文献
103.
104.
105.
ABSTRACT The effects of differential manganese (Mn) supply (0 to 355 μ M) and pH (4.8 and 6.0) on dry weight (DW), tissue concentrations of Mn, exudation of carboxylates, and the peroxidase activity were studied in ryegrass (Lolium perenne L.) and white clover (Trifolium repens L.) grown in nutrient solution. In both plant species, the increase in Mn supply caused a significant reduction in DW due to severe Mn toxicity, especially at pH 4.8. The critical toxicity concentration of Mn in shoots was 421 mg kg? 1 for ryegrass and 283 mg kg? 1 for white clover. For both plant species, an increase in Mn supply levels stimulated the exudation of carboxylates and the activity of peroxidase, which was related to stress conditions. The highest amount of carboxylates was exuded at pH 4.8. There was no clear effect of carboxylates on the complexation of Mn2 +. 相似文献
106.
? The objective of this study was to evaluate and compare nitrogen losses during the composting process developed at two facilities. Both are in Catalonia, which is located in northeast Spain. The research evaluated the effects of process, feedstock content, differences in compost maturity and other factors to explain differences in nitrogen levels. Separation methods and leachate problems were also compared. 相似文献
107.
Alejandro Cánepa Silvana B. Basack Norma B. Casabé Noemí R. Verrengia Guerrero 《Journal of Soils and Sediments》2013,13(4):775-782
Purpose
The relative sensitivity of two freshwater invertebrate organisms to the organophosphorus insecticide fenitrothion was assessed by measuring cholinesterase (ChE) activity, a well-known biomarker of both exposure and effect to organophosphorus pesticides. The influence of different concentrations of humic acids (HAs) and particulate matter on fenitrothion bioavailability was assessed in the more sensitive species.Materials and methods
The selected invertebrates were the dwelling feeding oligochaete Lumbriculus variegatus and the pulmonate gastropod Biomphalaria glabrata. Acute 48-h bioassays were performed exposing organisms to different fenitrothion concentrations. The concentrations that induced 50 % inhibition of enzyme activity (EC50) were calculated. Fenitrothion bioavailability was investigated using different concentrations of commercial HA or particulate matter. Sand and a diverse selection of chromatographic resins that have been proposed as analogues of natural sediments were selected. For these experiments, animals were exposed to a fenitrothion value similar to the EC50.Results and discussion
The 48-h EC50 values were 12?±?2 and 23?±?3 μg?l?1 for L. variegatus and B. glabrata, respectively. Depending on HA concentration and the characteristics of particles, ChE activity was similar or higher than the value recorded for animals exposed only to the pesticide in aqueous solution.Conclusion
The results indicated that L. variegatus was the more sensitive species of the two. In this species, fenitrothion bioavailability did not increase due to the presence of either different HA concentrations or particulate matter. The experimental approach may constitute a useful tool to predict the influence of dissolved organic matter and sediment particles on fenitrothion bioavailability and toxicity to non-target aquatic invertebrates. 相似文献108.
Maria Oliveira Cristian De La Fuente Martí Pumarola Sònia Añor 《Veterinary radiology & ultrasound》2014,55(3):300-304
A 3‐year‐old, intact female Golden Retriever was presented with acute tetraplegia. Neurologic examination was consistent with a C1–C5 myelopathy. On magnetic resonance (MR) imaging a well‐defined, extradural mass was detected within the spinal canal at the level of C1–C2. The mass was isointense to normal spinal cord gray matter on T1‐weighted (T1W) images, hyperintense on T2‐weighted (T2W), and gradient‐echo (GE) images, and enhanced homogeneously after intravenous contrast administration. MR imaging features were mainly consistent with a meningioma. Surgical treatment was refused by the owners, and the dog was euthanized. Postmortem examination demonstrated that the intraspinal mass was a schwannoma. 相似文献
109.
Cristian de la Fuente Martí Pumarola Sònia Añor 《Veterinary radiology & ultrasound》2014,55(4):424-427
An 8‐year‐old, male Boxer was examined for an acute onset of ambulatory paraparesis. Neurologic examination was consistent with a T3‐L3 myelopathy. Myelography revealed an extradural spinal cord compression in the region of the T10‐T13 vertebrae. On magnetic resonance (MR) imaging, a well‐defined epidural mass lesion was detected. The mass was mildly hyperintense on T1‐weighted, hyperintense on T2‐weighted and STIR images compared to normal spinal cord and enhanced strongly and homogenously. Postmortem examination confirmed a primary epidural hemangiosarcoma. Findings indicated that the MRI characteristics of spinal epidural hemangiosarcoma may mimic other lesions including meningioma and epidural hemorrhages/hematomas of non‐neoplastic etiology. 相似文献
110.
João B. Rodrigues Stéphane Araújo Fidel Sanroman-Llorens Estela Bastos Fidel San Roman Carlos Viegas 《Journal of Equine Veterinary Science》2013
Recent clinical and post-mortem studies documented a high prevalence of dental disorders in donkeys, but less information appears to be available specifically about incisor disorders in donkeys. A study to investigate the prevalence of oral and dental disorders affecting incisor teeth was performed, in two endangered breeds of donkeys: the Mirandês Donkey and the Zamorano-Leonés Donkey, through a prospective cross-sectional study in 800 donkeys, divided in 7 age groups (ranging 0-34 years), in 86 villages inside their geographic area of distribution, thinking on welfare and genetic preservation issues. The 74% of donkeys suffer from incisors disorders, ranging from 56.8% in the youngest group to 90.3% in group 7. Craniofacial abnormalities (49.25%), abnormalities in the occlusal surface (21.63%), fractures (17%), periodontal disease (16.13%) and diastemata (14.38%) were the main disorders recorded. Incisors disorders are significant, presenting at a much higher prevalence when compared to other studies involving the incisor teeth of equids, affecting all ages but particularly in older animals. This study provide essential information in dentistry applied to donkeys but also highlighted the importance of regular dental care in endangered breeds, improving their welfare and preserving a unique genetic heritage. 相似文献