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101.
102.
Lisa Scott Paula Menzies Richard J. Reid-Smith Brent P. Avery Scott A. McEwen Catherine S. Moon Olaf Berke 《Canadian journal of veterinary research》2012,76(2):109-119
The purpose of this study was to examine the prevalence and patterns of antimicrobial resistance (AMR) in enteric bacteria obtained from Ontario sheep flocks, and associations between antimicrobial use (AMU) and AMR. Forty-nine sheep producers participated for a 1-year interval between 2006 and 2008. Two-hundred and eighty-three pooled fecal samples were collected from the flocks during initial and final visits. Up to 3 isolates of Salmonella spp. and generic E. coli per pooled fecal sample were tested for susceptibility to 15 antimicrobials. Resistance was infrequent among Salmonella (0%, n = 7 isolates) and low among E. coli (13.1%; n = 849) isolates. A small number of isolates were resistant to antimicrobials classified as being of very high importance to human health. Tetracycline resistance was most frequently observed (12.0%). Logistic regression was used to model potential AMU (qualitative and quantitative) risk factors for tetracycline resistance in generic E. coli from final visits. Qualitative analysis indicated that the use of injectable sulfonamides [including trimethoprim-sulfonamide combinations (TMS)] and tetracycline in the feed and water were significantly associated with tetracycline resistance (OR = 2.6, P = 0.01; and OR = 4.8, P ≤ 0.01, respectively). Quantitative analysis also indicated that TMS exposure rate was significantly associated with tetracycline resistance, which varied depending on the exposure rate. The exposure rate of tetracycline in the feed and water was only significant after the removal of one influential flock, warranting further research examining flocks with higher tetracycline exposure rates. Although the prevalence of AMR in participating flocks was relatively low, risk factors for resistance were identified. 相似文献
103.
This is a report from a workshop on canine cancer registration hosted at the Norwegian School of Veterinary Science in Oslo in August 2010. The aim is to present a summary of the current efforts to gather data on canine (and feline) cancer based on information from participants at the workshop. A definition and classification of cancer registries is provided together with an inventory of the databases presented. Particular focus is placed on the distinction between population-based and hospital-based cancer registries. Future challenges are discussed and issues relating to harmonization of diagnostic coding, defining the population-at-risk, individual animal identification and data quality are included. Finally, other groups working within the field of cancer registration in companion animals are encouraged to contact the authors for future collaboration. 相似文献
104.
Journal of Soils and Sediments - This study assessed the efficacy of selected silicon-rich soil amendments in terms of their ability to provide dissolved silicon (Si) to soil solutions during a... 相似文献
105.
Clinical and histologic findings of conjunctival dermoids in two unrelated guinea pigs are described. The dermoids were treated surgically by resection with superficial lamellar keratectomy and corneal epithelial debridement. Histologically the dermis underneath a stratified squamous keratinized and variably pigmented epithelium consisted of multiple hair follicles, with clearly visible arrectores pilorum muscles, sebaceous glands and loose vascularized fatty tissue. 相似文献
106.
Olaf Zimmermann 《Gesunde Pflanzen》2004,56(6):151-156
Zusammenfassung Die Anwendung von Nutzarthropoden und entomopathogenen Nematoden hat in den letzten Jahren stetig zugenommen. Die Anfänge des biologischen Pflanzenschutzes mit Nützlingen in Deutschland liegen schon einige Jahrzehnte zurück. Im Freiland werden Trichogramma-Schlupfwespen seit über 25 Jahren gegen den Maiszünsler eingesetzt. Der Einsatz von Nützlingen unter Glas geht in die beginnenden 1970er zurück. Seit Anfang der 1980er werden in Deutschland Nützlinge produziert und kommerziell angeboten.Die etwa 60 eingesetzten Nützlinge sind zu mehr als 50% heimische Arten. Die von deutschen Firmen angebotenen nichtheimischen Arten sind nur an das Gewächshausklima angepasst und können dadurch nicht zur Gefahr in heimischen Ökosystemen werden. In Gewächshauskulturen, besonders in Tomaten und Gurken, ist zu fast 100% Pflanzenschutz durch Nützlinge möglich. In anderen Kulturen, wie Zierpflanzen, ist ein integrierter Schutz mit nützlingsschonenden Pflanzenschutzmitteln notwendig. Besonders Imidacloprid und verwandte, systemisch wirkende Pflanzenschutzmittel zeigen starke Nebenwirkungen auf Nützlinge.Der biologische Vorratsschutz mit Nützlingen ist seit über 6 Jahren in der Praxis erfolgreich. Biologische Bekämpfungskonzepte ermöglichen vom Getreidelager bis zum Haushalt einen verbraucherfreundlichen Schutz der Lebensmittel.In 2001 wurde der Verein der Nützlingsanbieter in Deutschland e. V. gegründet, um gemeinsame Interessen der Firmen zu vertreten. Eine Homepage soll als Informationsplattform der interessierten Öffentlichkeit die Möglichkeiten der biologischen Schädlingsbekämpfung mit Nützlingen näher bringen. 相似文献
107.
108.
S. Craig DeLong Glenn D. Sutherland Lori D. Daniels Ben H. Heemskerk Ken Olaf Storaunet 《Forest Ecology and Management》2008,255(10):3613-3620
Patterns of tree mortality, rates and type of tree and snag fall, and relationships between snag characteristics and potential wildlife habitat value were estimated for hybrid spruce (Picea glauca (Moench) Voss × engelmannii Parry ex Engelm.) and subalpine fir (Abies lasiocarpa (Hook.) Nutt.) in east-central British Columbia in order to provide important parameters for deadwood modelling. We sampled 172 snags (52 spruce and 120 fir) for species, size, morphological, and habitat attributes, and used dendroecological techniques on a subsample of these (n = 158) to estimate year of death. Input of snags appeared to occur at a nearly constant rate in these stands. Estimated annual tree fall, including live trees and snags, was 5.3% for hybrid spruce and 6.1% for subalpine fir and stem breakage was more frequent than uprooting. Long-term annual snag fall rates were 4.6% for hybrid spruce and 2.9% for subalpine fir. Discriminant analysis based on time since death correctly classified snags into three decay classes for 85% and 72% of spruce and fir, respectively. Snags that potentially could provide important functions for wildlife habitat were more prevalent in fresh and intermediate classes for hybrid spruce and in intermediate and old classes for subalpine fir. The results provide valuable parameters for further development of deadwood models, which are an important tool for development of best practices for deadwood management. 相似文献
109.
Cathrine Trangerud Håvard Bjørgen Erling Olaf Koppang Randi Nygaard Grøntvedt Hege Kippenes Skogmo Nina Ottesen Agnar Kvellestad 《Journal of fish diseases》2020,43(3):379-389
Pathological changes in the vertebral column of farmed Atlantic salmon in Norway have been reported since the 1990s. Based on the characteristic radiographic findings, we here present a vertebral column deformity named “curved cross-stitch vertebrae” that mainly affects the middle aspect of the vertebral column. Sixty fish, from the west/northwest coast of mid-Norway, were sampled at slaughter and examined by radiography, computed tomography (CT), necropsy, macrophotography, and histology. The vertebral deformities were radiographically graded as mild, moderate, or marked. The main differences between these grades of changes were defined by increased curving of the peripheries of endplates, reduced intervertebral spaces, and vertical displacement of the vertebrae. The curved rims of endplates were located peripheral to a continuous and approximately circular borderline. The CT studies revealed small, multifocal, hypo-attenuating, round to crescent-shaped areas in the notochord, compatible with the presence of gas. Additionally, histology revealed that the axial parts of endplates had circular zones with perforations, through which either notochordal tissue prolapsed into the vertebrae or vascularized fibrochondroid proliferations extended from the vertebrae into the notochord. Inflammation was present in many vertebral bodies. To the best of our knowledge, this is the first report of gas in the notochord of fish. 相似文献
110.
- Many conservation efforts for freshwater fishes have been undertaken; however, continuing the monitoring of both the distribution and the abundance of species to determine the effectiveness of these actions can be difficult. As species increase in rarity, they are more difficult to detect in the field, making inferences on occupancy less reliable.
- Conventional sampling methods, such as electrofishing and seining, require the physical handling of rare fishes, which may cause stress and mortality and, consequently, compromise conservation goals and limit monitoring programmes. Non‐invasive surveillance methods, including underwater video, are playing an increasingly important role.
- In this study, occupancy models were used to estimate the detection probability of underwater cameras as an alternative to the conventional sampling methods for rare stream fishes. Redside dace (Clinostomus elongatus), a small minnow listed as Endangered, was used as a model organism for rarity. A total of 69 historical redside dace sites were sampled using three sampling methods to determine the effect of gear type on detecting and identifying the habitat preferences of this rare minnow.
- On average, using multiple underwater cameras is as effective at detecting a rare minnow as conventional sampling methods (backpack electrofisher and seine) and causes no harm.
- The detection probability of both underwater cameras and backpack electrofishing were adversely affected by turbidity, whereas seining was positively affected by stream velocity. The probability of occupancy of redside dace is driven by open channels and sediment size, and this provides a strong basis for informing stream restoration projects.
- The use of multiple underwater cameras over conventional sampling methods is recommended when sampling for rare and endangered minnows in systems with low turbidity.