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721.
A 9-year-old, female spayed, Domestic Long-haired cat was presented with bilateral, progressive, pink-white corneal opacities. The referring veterinarian had diagnosed feline herpesvirus-1 (FHV-1) keratitis though diagnostics for FHV-1 had not been performed and treatment with antibiotics and antivirals did not improve the condition. Histopathology showed neutrophils, plasma cells and lymphocytes, but no eosinophils or mast cells. Routine diagnostics did not find an underlying cause, but Southern blot analysis for FHV-1 was positive. The cat responded to topical corticosteroids and cyclosporine when used consistently. 相似文献
722.
José A Orden Carmen Cortés José A Ruiz-Santa-quiteria Susana Martínez Ricardo de la Fuente 《Journal of veterinary diagnostic investigation》2005,17(1):65-67
A total of 163 verotoxin-producing Escherichia coli (VTEC) strains isolated from diarrheic and healthy cattle, sheep, and goats were analyzed for the presence of the saa gene by polymerase chain reaction. Seventeen (45.9%) and 5 (29.4%) of the VTEC isolated from healthy cattle and diarrheic calves, respectively, had the saa gene. None of the saa-positive strains carried the eae gene, but 20 of the 22 saa positive were ehxA positive. In contrast with cattle VTEC, none of the VTEC isolated from small ruminants were saa positive. These results show that the saa gene is commonly associated with bovine eae-negative VTEC strains but not with ovine or caprine VTEC strains. 相似文献
723.
Debora Tura Carmen Gigliotti Stefano Pedò Osvaldo Failla Daniele Bassi Arnaldo Serraiocco 《Scientia Horticulturae》2007
Oxidation stability is an important property of olive oil quality and is affected by different antioxidant compounds whose levels may be influenced by cultivar, year and place of production. Polyphenols, tocopherols, carotenoids, chlorophylls and fatty acids levels were correlated to oxidative stability in olive oils from three experiments: cultivar influence (18 cultivars assessed for 4 years in the same place); environmental influence by mesoclimatic (4 cultivars from 17 sites in a single region for 4 years) and macroclimate conditions (3 cultivars from 3 different regions for 3 years). Total polyphenols and saturated on polyunsaturated fatty acids ratio were shown to be the major factors in oil antioxidant stability, according to multivariate regression models. Among the surveyed cultivars, oils from ‘Leccino’ and from three ‘local’, minor cultivars (‘Miniol’, ‘Regina’ and ‘Rossanello’) resulted in higher oxidative stability and oils from cultivars grown in Tuscany (central Italy) showed the highest oxidative stability by comparison with northern and southern regions. 相似文献
724.
Juan Jesús Medina Isabel Clavero-Ramírez María Elena González-Benito Josefa Gálvez-Farfán José Manuel López-Aranda Carmen Soria 《Scientia Horticulturae》2007
This study compares agronomic traits of two cultivars of strawberry in plants derived from conventional propagation, micropropagation and cryopreserved apices. The agronomic traits evaluated were fruit production and fruit quality. Differences were found in some of the fruit production traits studied in the plants post-micropropagation and post-cryopreservation when compared to conventionally propagated plants of the cultivar ‘Andana’; showing the first two groups higher second class yield and smaller fruits. Plants of the cultivar ‘Camarosa’ post-cryopreservation showed differences in traits related to fruit quality when compared to the other two groups of plants (internal colour, firmness and soluble solids). No adverse effect on agronomic traits could be associated with the use of cryopreservation. Plants from in vitro and cryopreservation origin were phenotypically similar to the conventional propagated plants in production field. 相似文献
725.
Romalde JL Ravelo C Valdés I Magariños B de la Fuente E Martín CS Avendaño-Herrera R Toranzo AE 《Veterinary microbiology》2008,130(1-2):198-207
This work describes the characterization of the causal agent of disease outbreaks that, from 1999, occurred repeatedly during the summer months (temperatures higher than 15 degrees C) in Atlantic salmon (Salmo salar) cage-farmed in Chile affecting both smolts and adult fish cultured in estuary and marine waters, reaching in some occasions a cumulative mortality up to 25% of the affected population. Diseased fish showed exophthalmia with accumulation of purulent and haemorrhagic fluid around eyes, and ventral petechial haemorrhages. At necropsy, haemorrhage in the abdominal fat, pericarditis, and enlarged liver, spleen and kidney are common pathological changes. Gram-stained smears revealed the presence of Gram-positive cocci, beta-hemolytic, negative for oxidase and catalase tests. Although biochemical characterization of the isolates using the miniaturized system rapid ID 32 Strep suggested their assignation to genus Gemella, sequencing and RFLP analysis of the 16S rRNA revealed that bacteria associated with the mortalities belong to Streptococcus phocae. Serological studies demonstrated that all the salmon isolates are antigenically homogeneous, which can facilitate the development of preventive measures and, although sharing some antigenical determinants, they belong to a different Lancefield group than the type strain isolated from seals. On the basis of these facts, we conclude that the species S. phocae is an emerging pathogen for salmonid culture in Chile, and it should be included as a new member of the warm water streptococcosis. 相似文献
726.
727.
728.
Phenotypic and genotypic characterization of antimicrobial resistance in faecal enterococci from wild boars (Sus scrofa) 总被引:1,自引:0,他引:1
The objective was to study the prevalence of antimicrobial resistance and the mechanisms implicated in faecal enterococci of wild boars in Portugal. One hundred and thirty-four enterococci (67 E. faecium, 54 E. hirae, 2 E. faecalis, 2 E. durans and 9 Enterococcus spp.) were recovered from 67 wild boars (two isolates/sample), and were further analysed. High percentages of resistance were detected for erythromycin, tetracycline, and ciprofloxacin (48.5%, 44.8%, and 17.9%, respectively), and lower values were observed for high-level-kanamycin, -streptomycin, chloramphenicol, and ampicillin resistance (9%, 6.7%, 4.5%, and 3.7%, respectively). No isolates showed vancomycin or high-level-gentamicin resistance. The erm(B), tet(M), aph(3')-IIIa, and ant(6)-I genes were demonstrated in all erythromycin-, tetracycline-, kanamycin-, and streptomycin-resistant isolates, respectively. Specific genes of Tn916/Tn1545 and Tn5397 transposons were detected in 78% and 47% of our tet(M)-positive enterococci, respectively. The tet(S) and tet(K) genes were detected in one isolate of E. faecium and E. hirae, respectively. Three E. faecium isolates showed quinupristin-dalfopristin resistance and the vat(E) gene was found in all of them showing the erm(B)-vat(E) linkage. Four E. faecium isolates showed ampicillin-resistance and all of them presented seven amino acid substitutions in PBP5 protein (461Q-->K, 470H-->Q, 485M-->A, 496N-->K, 499A-->T, 525E-->D, and 629E-->V), in relation with the reference one; a serine insertion at 466' position was found in three of the isolates. Faecal enterococci from wild boars harbour a variety of antimicrobial resistance mechanisms and could be a reservoir of antimicrobial resistance genes and resistant bacteria that could eventually be transmitted to other animals or even to humans. 相似文献
729.
Carmen Sotelo Montes John C. Weber Dimas A. Silva Clarice Andrade Graciela I. B. Muñiz Rosilei A. Garcia Antoine Kalinganire 《New Forests》2014,45(2):179-197
In the Sahelian and Sudanian ecozones of West Africa, the rainy season lasts only 3–4 months per year, there are steep rainfall gradients with latitude and longitude, the climate is becoming increasingly hotter and drier with more variable rainfall, some fuelwood species are disappearing locally, demand for fuelwood is increasing, and we expect that fuelwood production will be increasingly limited to drier sites in the future. We need a methodology, therefore, to identify the best species for fuelwood production in drier sites. We used a methodology that could be used to identify the best fuelwood species for drier and wetter sites in regions where there are steep rainfall gradients. We investigated variation in growth and fuelwood properties of five species (Balanites aegyptiaca, Combretum glutinosum, Guiera senegalensis, Piliostigma reticulatum, Ziziphus mauritiana) along rainfall gradients. Growth parameters (tree height, stem diameter under bark, mean ring width) and fuelwood properties (basic density, volatile matter, fixed carbon, ash content, moisture content, gross calorific value, gross calorific value per cubic meter, fuel value index) were adjusted for tree age. For each species, linear regressions were used to determine the effects of mean annual rainfall and geographical coordinates, which were correlated with rainfall, on tree growth and fuelwood properties; and the effects of tree growth on fuelwood properties in lower, intermediate and higher rainfall zones. Geographical coordinates explained more variation than rainfall, and relationships with rainfall differed among species. Larger trees had wood with higher basic density, fixed carbon, ash content, moisture content, gross calorific value and/or gross calorific value per cubic meter, but lower volatile matter and/or fuel value index. Relationships between growth and fuelwood properties were not significant in all species and rainfall zones. Based on this study, we recommend producing fuelwood of C. glutinosum and G. senegalensis. 相似文献
730.
Pablo Casta?o Miguel Fuertes Ignacio Ferre Miguel Fernández Maria del Carmen Ferreras Javier Moreno-Gonzalo Camino González-Lanza Frank Katzer Javier Regidor-Cerrillo Luis Miguel Ortega-Mora Valentín Pérez Julio Benavides 《Veterinary research》2014,45(1):9
After oral administration of ewes during mid gestation with 2000 freshly prepared sporulated oocysts of T. gondii isolate M4, abortions occurred between days 7 and 11 in 91.6% of pregnant and infected ewes. Afterwards, a further infection was carried out at late gestation in another group of sheep with 500 sporulated oocysts. Abortions happened again between days 9 and 11 post infection (pi) in 58.3% of the infected ewes. Classically, abortions in natural and experimental ovine toxoplasmosis usually occur one month after infection. Few experimental studies have reported the so-called acute phase abortions as early as 7 to 14 days after oral inoculation of oocysts, and pyrexia was proposed to be responsible for abortion, although the underline mechanism was not elucidated. In the present study, all placentas analysed from ewes suffering acute phase abortions showed infarcts and thrombosis in the caruncullar villi of the placentomes and ischemic lesions (periventricular leukomalacia) in the brain of some foetuses. The parasite was identified by PCR in samples from some placentomes of only one sheep, and no antigen was detected by immunohistochemical labelling. These findings suggest that the vascular lesions found in the placenta, and the consequent hypoxic damage to the foetus, could be associated to the occurrence of acute phase abortions. Although the pathogenesis of these lesions remains to be determined, the infectious dose or virulence of the isolate may play a role in their development. 相似文献