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ABSTRACT Disturbances, including natural phenomena and forest management activities such as thinning, reforestation, rehabilitation seeding, and livestock grazing, are often associated with changes that make systems more susceptible to invasion by nonindigenous species (NIS). However, the susceptibility of a landscape to any particular species is not uniform. To prevent and manage (NIS) effectively we need to understand the effect of different types of disturbance on such species and understand how these effects vary on the landscape. Such an understanding is required in a general way for different nonindigenous taxa, but also for specific species or species associations in order to be able to develop comprehensive management plans. We performed three reviews, one each for nonindigenous plants, pathogens, and insects concerning the effect of a range of different forest management activities on their occurrence, spread, and spatial distribution in the United States of America. Much remains to be understood about the processes and patterns of invasion at the finer spatial landscape scales (e.g., < 50 m) that are most relevant to management decisions for a specific area. 相似文献
123.
Olga Rubilar Gonzalo R. Tortella Raphael Cuevas Mara Cea Susana Rodríguez-Couto María Cristina Diez 《Water, air, and soil pollution》2012,223(5):2463-2472
This study investigates pentachlorophenol (PCP) adsorption by the white-rot fungus Anthracophyllum discolor in a fixed-bed column reactor. PCP adsorption at different concentrations (20, 30, and 50?mg?L?1) and pH values (5.0, 5.5, and 6.0) was determined and modeled using the Thomas model. Fourier transform infrared spectroscopy (FTIR) was used to identify functional groups of biomass that may participate in the interaction of PCP. The biosorption capacity of A. discolor was pH-dependent, and the PCP adsorbed increased with the decrease in the pH solution. Acid pH values of the influent gave an increase in saturation time in all PCP concentrations. By contrast, the increase in PCP concentration caused that the binding sites were filled quickly, resulting in a decrease in saturation time. The Thomas model was found suitable for describing the entire dynamic of the column with respect to the PCP concentration and pH of the solution. FTIR results showed that amines, carboxylates, alkanes, and C?CO groups might participate in the PCP adsorption on the biomass surface. It was concluded that A. discolor biomass was a good adsorbent for PCP removal from influent with mainly acidic pH. 相似文献
124.
Mara H. Saalfeld Daniela I. B. Pereira Jessica L. Borchardt Regis T. Sturbelle Matheus C. Rosa Marcio C. Guedes Marcia A. Gularte Fábio P. Leivas Leite 《Animal Science Journal》2014,85(11):963-967
Colostrum silage is an anaerobic fermentation methodology of excess farm colostrum used to conserve and provide as milk replacement for calves. The present study aimed to evaluate the levels of immunoglobulins present in bovine colostrum silage and its absorption by newborn calves. The concentration of immunoglobulins was determined in fresh colostrum and colostrum silage stored for 12 months. The absorption of immunoglobulins by calves was assessed immediately after birth and 24 h after colostrum silage intake. The immunoglobulin levels were evaluated by ELISA. The results highlighted that colostrum silage kept similar levels of immunoglobulins as the ones in colostrum in natura, and can be transferred to newborn calves with similar amounts to calves fed with colostrum in natura. It is concluded that colostrum silage keeps viable immunoglobulins, and is able to transfer passive immunity to newborn calves. 相似文献
125.
Germán J Cantón Frank Katzer Stephen W Maley Paul M Bartley Julio Benavides-Silván Javier Palarea-Albaladejo Yvonne Pang Sionagh H Smith Mara S Rocchi David Buxton Elisabeth A Innes Francesca Chianini 《Veterinary research》2014,45(1):11
Infection with Neospora caninum stimulates host cell-mediated immune responses, which may be responsible for placental damage leading to bovine abortion. The aim of this study was to compare immune responses in the bovine placenta, following experimental infection in different stages of pregnancy. Placentomes were examined by immunohistochemistry and inflammation in early gestation was generally moderate to severe, particularly in the placentas carrying non-viable foetuses, whereas it was milder in later stages, mainly characterised by the presence of CD3+, CD4+ and γδ T-cells. This distinctive cellular immune response may explain the milder clinical outcome observed when animals are infected in later gestation. 相似文献
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127.
Enrico Bigliardi Laura Denti Valeria De Cesaris Mara Bertocchi Francesco Di Ianni Enrico Parmigiani Carla Bresciani Anna Maria Cantoni 《Reproduction in domestic animals》2019,54(1):63-71
Testicular tumours are the most common neoplasms in male dogs accounting for approximately 90% of all tumours affecting the genitourinary tract. Gray‐scale ultrasonography in combination with colour and power Doppler imaging has been well accepted as an accurate technique for assessing scrotal lesions and vascularization of the testis. Colour Doppler sensitivity for low blood flows appears promising in the study of testicular disorders. The aim of this study was to assess if colour and power Doppler ultrasound is a good tool for the investigation of testicular lesions in dogs, to report the sonographic features of lesions and to measure colour and power Doppler parameters such as resistive index (RI), pulsatility index (PI), hypovascularization and hypervascularization (VI) determining if they can be used to distinguish testicular neoplasms from the wide spectrum of non‐neoplastic pathological findings. In this study, 50 male dogs of various breeds, aged between 7 and 14 years, presented with testicular disorders were selected. RI and PI were calculated. Mean RI values for neoplastic, inflammatory and degenerative lesions were 0.54, 0.45 and 0.58, respectively. Mean PI values were 0.62, 0.55 and 0.63, respectively. Hypovascularization and hypervascularization of the lesion were evaluated throughout the vascularity index (VI). Vascular signals in neoplasms were significantly intensified around and inside the mass if compared with those measured during inflammatory and degenerative lesions. VI markedly increased in solid tumours. Pathological testes were removed; macroscopical, histological and immunoistochemical evaluations were carried out. Colour Doppler showed increased intralesional and peripheral flows in all neoplastic lesions analysed. No flows were detected around cysts. 相似文献
128.
129.
Griebel PJ Entrican G Rocchi M Beskorwayne T Davis WC 《Veterinary immunology and immunopathology》2007,119(1-2):115-122
A panel of 377 commercially available mAbs was submitted to the animal homologue section of the Eighth International Workshop on Human Leukocyte Differentiation Antigens (HLDA8, Adelaide, Australia) for cross-reactivity studies in a range of vertebrate species. Eight commercial suppliers participated by providing isotype controls and mAbs specific for a total of 144 CD antigens. In this study, we describe the results of flow cytometric testing of the reactivity of these mAbs with leukocyte populations isolated from blood, bronchoalveolar lavage, and ileal Peyer's patches of sheep. A total of 52 mAbs were identified as potentially reacting with sheep blood leukocytes in the first round of screening with blood leukocytes. In the second phase, reactivity of selected mAbs was further analyzed by repeating the screening with blood leukocytes at an independent facility. Screening of selected mAbs for reactivity with myeloid antigens was completed with alveolar macrophages and screening for reactivity with B cell antigens was completed with ileal Peyer's patch B cells. This screening identified mAbs that consistently reacted with both putative myeloid (CD10, CD22, CD23, CD27, CD29, CD32, CD49d, CD81, CD86, CD88, CD163, CD165) and B cell (CD10, CD22, CD23, CD27, CD29, CD32, CD49d, CD81, CD86, CD88, CD165) activation or differentiation antigens. Further studies will be required to determine if each mAb cross-reacts with an orthologous leukocyte antigen. 相似文献