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排序方式: 共有350条查询结果,搜索用时 578 毫秒
81.
Raquel Yvonne Arantes Baccarin Marco Antonio Pereira Neimar Vanderlei Roncati Rafael Ramalho Corso Bergamaschi Stefano Carlo Filippo Hagen 《The Canadian veterinary journal. La revue veterinaire canadienne》2012,53(10):1079-1084
This study aimed to detect, by radiographic examination, the evolution of osteochondral lesions in the tarsocrural and femoropatellar joints of Lusitano foals. Within 1 month of age, 76.08% of foals had radiographic signs of osteochondrosis, but only 16.20% had lesions at 18 months. The radiographic signs resolved by 5 mo of age in most foals, but some cases that involved either joint, were not resolved until 12 mo of age. It is thought that the “age of no return” is 5 mo for the tarsocrural and 8 mo for the femoropatellar joint but this study demonstrated regression of osteochondral lesions in both joints of Lusitano foals up to 12 months of age. 相似文献
82.
Objectives To describe and evaluate the use of equine amniotic membrane trans‐plantation after lamellar keratectomy for the treatment of corneal sequestrum in cats. Methods Six cats (seven eyes) of various breed and ages with corneal sequestra were treated surgically with lamellar keratectomy and amniotic membrane transplantation. All the sequestra and a small piece of the amniotic membranes used for each surgery were submitted for histopathologic examination. Results Five of the seven eyes showed minimal level of scarring in the cornea and good transparency. No recurrences of the sequestra have been noted during the follow‐up period (3–9 months). One eye had necrosis of the amniotic membrane 2 weeks after the surgery. The sequestrum of this eye showed a high level of bacterial contamination on histopathology. Three months later the same cat developed a descemetocele in the area where the necrotic amniotic membrane was rejected. A second eye developed a perforation under the amniotic membrane two weeks after the surgery. The sequestrum of this eye was deep and without vascularization. Conclusion Amniotic membrane transplantation after lamellar keratectomy was a valid procedure for surgical treatment of corneal sequestrum in cats. The procedure resulted in excellent cosmesis and functional vision in five of seven eyes; although case selection is important, particularly to exclude the very deep and non‐vascularized sequestra. 相似文献
83.
Schmidt Christoph Stephan Agostini Francesco Simon Ana-maria Whyte Jennifer Townend John Leifert Carlo Killham Ken Mullins Chris 《European journal of plant pathology / European Foundation for Plant Pathology》2004,110(10):1025-1046
In five different soils originating from Scotland (Craibstone and Cruden Bay), Germany (Magdeburg and Uelzen) and Greece (Tymbaki), Pseudomonas fluorescens B5 reached higher population sizes (4.7–5.7logCFU/plant) on 12-day-old sugar beet seedlings than Bacillus subtilis MBI 600 (4.1–4.8logCFU/plant). Total population size per plant was not affected by soil type. In all five soils, the antagonists reached highest population densities in the hypocotyl and the upper 2cm root section (P. fluorescensB5: 5.2–6.8log10CFU/g plant fresh weight, Bacillus subtilisMBI 600: 5.2–6.1log10CFU/g plant fresh weight) and declined to 0–3log10CFU below 4cm root depth. Colonisation by P.
fluorescens B5 down the root was slightly increased in the soils from Craibstone, Magdeburg, and Uelzen compared to the sandy clay loam from Tymbaki. In lux-marked P.
fluorescens B5, population density was positively correlated with light emission in all soils; the light emission indicated physiological activity of the strains. However, P.
fluorescens B5 reduced Pythium damping-off (measurement after 14 days plant growth) only in three of the five soils (Craibstone, Cruden Bay and Magdeburg). Co-inoculation of B.
subtilis MBI 600 increased downward colonisation of the root by P.
fluorescens B5, but not the total population ofP.
fluorescens B5 per plant. Bacillus
subtilisMBI 600 did not reduce Pythium damping-off in any of the soils nor did it influence the efficiency of co-inoculated P.
fluorescens B5; its population consisted mainly of physiologically inactive spores. In Craibstone soil, pH did not affect population density, distribution along the root or biocontrol activity against P. ultimum of P.
fluorescens B5 or B.
subtilis MBI 600. 相似文献
84.
Edyta Halupecki Carlo Bazzi Susanne Jock Klaus Geider Damir Đermić Bogdan Cvjetković 《European journal of plant pathology / European Foundation for Plant Pathology》2006,114(4):435-440
Erwinia amylovora is the causative agent of fire blight, a destructive disease of rosaceous plants. The European population can be divided
into several subtypes according to differences in restriction fragment length polymorphism of the XbaI genomic DNA digest analysed with pulsed-field gel electrophoresis. This technique was also used to determine the genetic
relatedness of six Croatian isolates to the E. amylovora types found in the countries surrounding Croatia. The isolates belong to the Pt2 pattern type that is characteristic of the
East Mediterranean basin. All tested isolates gave essentially the same total cell protein pattern in SDS-polyacrylamide gel
electrophoresis. The number of short-sequence DNA repeats in plasmid pEA29 of six isolates was determined by PCR assays and
ranged from four to seven. The isolates examined showed high pathogenicity in immature pear fruits. Differences were also
revealed in microbiological assays such as amylovoran synthesis, levan formation, siderophore production and colour on coliform
medium. 相似文献
85.
Photolysis of quinalphos, O,O-diethyl O-(quinoxalin-2-yl) phosphorothioate ( I ), in ethanolic solutions yields two products, O,O-diethyl O-(3-ethoxy-quinoxalin-2-yl) phosphorothioate ( II ) and O,O-diethyl O-(3-(1-hydroxyethyl)-quinoxalin-2-yl) phosphorothioate ( III ). Both products derive from the reaction of photo-excited quinalphos molecule with the solvent. The reactions follow first-order kinetics. A mechanism that accounts for the formation of the above mentioned products is proposed. 相似文献
86.
Gabriella Massolini Mikes Kitsos Carlo Gandini Gabriele Caccialanza 《Pest management science》1989,26(2):209-214
The free oximes and acetyl derivatives of a series of 4-substituted phenyl pyridyl ketones were prepared and tested in vitro and in vivo against fungal plant pathogens of different taxonomic classes. All compounds exhibited an interesting activity against some or all of the test fungi. The best results were given by the acetyl derivatives. 相似文献
87.
Marta Vascellari Silvia Tasca Tommaso Furlanello Erika Carli Carlo Patron Franco Mutinelli Marco Caldin 《Journal of veterinary diagnostic investigation》2007,19(2):205-208
An unusual clinical presentation of lymphoma with vertebral involvement in a dog is reported. A 20-month-old intact female Golden Retriever presented with progressive paraparesis and anorexia. Complete blood count and serum biochemistry profile demonstrated pancytopenia and hypercalcemia. Ventral fusion of the lumbar vertebrae by new bony tissue deposition was evident on X-ray and CT scan. Fine needle aspiration revealed neoplastic lymphoid cells in lymph nodes and bone marrow. Histologically, vertebral bone and osteophytes, liver, bone marrow, kidney, and lymph nodes were diffusely infiltrated by neoplastic, lymphoid cells, with scant cytoplasm and round hyperchromatic nuclei. Polyostotic and medullary T-cell lymphoma with spondylosis was diagnosed. Lymphoma mainly affecting bone is uncommon in the dog. The present case differs from previously described polyostotic lymphomas in clinical signs of the disease, mainly attributable to spondylarthrosis. In addition, lymphomatous proliferation was associated with osteoproductive lesions of the vertebrae. 相似文献
88.
Simazine biodegradation in soil: analysis of bacterial community structure by in situ hybridization 总被引:1,自引:0,他引:1
Pesticide and nitrate contamination of soil and groundwater from agriculture is an environmental and public health concern worldwide. Simazine, 6-chloro-N2,N4-diethyl-1,3,5-triazine-2,4-diamine, is a triazine herbicide used in agriculture for selective weed control with several types of crops and it is frequently applied to soils receiving N-fertilizers. Degradation experiments were performed in the laboratory to assess whether the biodegradation of simazine in soil may be influenced by the presence of urea. Simazine degradation rates under different experimental conditions (presence/absence of urea, microbiologically active/sterilized soil) were assessed together with the formation, degradation and transformation of its main metabolites in soil. Simazine degradation was affected by the presence of urea, in terms both of a smaller half-life (t(1/2)) and of a higher amount of desethyl-simazine formed. The soil bacterial community was also studied. Microbial abundances were determined by epifluorescence direct counting. Moreover in situ hybridization with rRNA-targeted fluorescent oligonucleotide probes was used to analyze the bacterial community structure. Fluorescent in situ hybridization (FISH) was used to detect specific groups of bacteria such as the alpha,beta,gamma-subdivisions of Proteobacteria, Gram-positive bacteria with a high G + C DNA content, Planctomycetes, Betaproteobacterial ammonia-oxidizing bacteria and nitrifying bacteria. The presence of the herbicide and/or urea affected the bacterial community structure, showing that FISH is a valuable tool for determining the response of bacterial populations to different environmental conditions. 相似文献
89.
Marta Mari Tiziano Cembali Lucia Casalini Gian Carlo Pratella 《European journal of plant pathology / European Foundation for Plant Pathology》2000,106(5):449-454
Strains of Mucor piriformis were isolated from orchard soils and from packinghouse dump-tank waters. Pathogen propagules were not found in fruit sample washings. M. piriformis was the most prevalent of the Mucor isolates, only one of 67 isolates was a different Mucor sp., possibly M. racemosus. The population of the pathogen propagules fluctuated in an annual cyclic pattern, declining in warm months and increasing after harvest. The viability of sporangiospores was markedly affected by rain. There was a good correlation (r=0.88) between the number of recovered propagules in the soil and the amount of rainfall. M. piriformis isolates caused decay on pear at 0°C after 14 days. 相似文献
90.
Increased nitrogen-use efficiency of a short-rotation poplar plantation in elevated CO(2) concentration 总被引:1,自引:0,他引:1
Calfapietra C Angelis Pd Gielen B Lukac M Moscatelli MC Avino G Lagomarsino A Polle A Ceulemans R Mugnozza GS Hoosbeek MR Cotrufo MF 《Tree physiology》2007,27(8):1153-1163
We estimated nitrogen (N) use by trees of three poplar species exposed for 3 years to free air CO(2) enrichment (FACE) and determined whether the CO(2) treatment affected the future N availability of the plantation. Trees were harvested at the end of the first 3-year rotation and N concentration and content of woody tissues determined. Nitrogen uptake of fine roots and litter was measured throughout the first crop rotation. The results were related to previously published variations in soil N content during the same period. We estimated retranslocation from green leaves and processes determining N mobilization and immobilization, such as mineralization and nitrification, and N immobilization in litter and microbial biomass. In all species, elevated CO(2) concentration ([CO(2)]) significantly increased nitrogen-use efficiency (NUE; net primary productivity per unit of annual N uptake), decreased N concentration in most plant tissues, but did not significantly change cumulative N uptake by trees over the rotation. Total soil N was depleted more in elevated [CO(2)] than in ambient [CO(2)], although not significantly for all soil layers. The effect of elevated [CO(2)] was usually similar for all species, although differences among species were sometimes significant. During the first 3-year rotation, productivity of the plantation remained high in the elevated [CO(2)] treatment. However, we observed a potential reduction in N availability in response to elevated [CO(2)]. 相似文献