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121.
Nadia Ruocco Roberta Esposito Marco Bertolino Gianluca Zazo Michele Sonnessa Federico Andreani Daniela Coppola Daniela Giordano Genoveffa Nuzzo Chiara Lauritano Angelo Fontana Adrianna Ianora Cinzia Verde Maria Costantini 《Marine drugs》2021,19(3)
Marine sponges commonly host a repertoire of bacterial-associated organisms, which significantly contribute to their health and survival by producing several anti-predatory molecules. Many of these compounds are produced by sponge-associated bacteria and represent an incredible source of novel bioactive metabolites with biotechnological relevance. Although most investigations are focused on tropical and temperate species, to date, few studies have described the composition of microbiota hosted by Antarctic sponges and the secondary metabolites that they produce. The investigation was conducted on four sponges collected from two different sites in the framework of the XXXIV Italian National Antarctic Research Program (PNRA) in November–December 2018. Collected species were characterized as Mycale (Oxymycale) acerata, Haliclona (Rhizoniera) dancoi, Hemigellius pilosus and Microxina sarai by morphological analysis of spicules and amplification of four molecular markers. Metataxonomic analysis of these four Antarctic sponges revealed a considerable abundance of Amplicon Sequence Variants (ASVs) belonging to the phyla Proteobacteria, Bacteroidetes, Actinobacteria and Verrucomicrobia. In particular, M. (Oxymycale) acerata, displayed several genera of great interest, such as Endozoicomonas, Rubritalea, Ulvibacter, Fulvivirga and Colwellia. On the other hand, the sponges H. pilosus and H. (Rhizoniera) dancoi hosted bacteria belonging to the genera Pseudhongella, Roseobacter and Bdellovibrio, whereas M. sarai was the sole species showing some strains affiliated to the genus Polaribacter. Considering that most of the bacteria identified in the present study are known to produce valuable secondary metabolites, the four Antarctic sponges could be proposed as potential tools for the discovery of novel pharmacologically active compounds. 相似文献
122.
Claudio Zucca Nadia Vignozzi Salvatore Madrau Mahmut Dingil Franco Previtali Selim Kapur 《植物养料与土壤学杂志》2013,176(4):529-539
The clearing of Mediterranean maquis along with the creation of new pasture land has been an important factor of soil and land degradation in the Mediterranean region. The present research compared soil aggregates and their intraporosity in paired pasture/maquis plots in central E Sardinia (Italy), to study the impact of land use change on soil structure. Undisturbed surface horizons were sampled for thin‐section analysis. Aggregate shape was compared and intraporosity was studied for representative aggregates at different depths. Furthermore, the interaction of root activity and grazing under pasture and maquis cover was discussed. The outcomes revealed a complex interplay of trampling and root activity effects. A decrease (–44%) in total voids (regular pores), along with higher aggregate regularity, was observed under pasture in the 0–2 cm layer, and an increase (+261%) in 50–100 μm planar (elongated) pores was determined in the 2–4 cm layer, suggesting a possible surface compaction due to trampling and an increased subsurface fine root activity by the grassland vegetation. 相似文献
123.
Meibom KL Blokesch M Dolganov NA Wu CY Schoolnik GK 《Science (New York, N.Y.)》2005,310(5755):1824-1827
The mosaic-structured Vibrio cholerae genome points to the importance of horizontal gene transfer (HGT) in the evolution of this human pathogen. We showed that V. cholerae can acquire new genetic material by natural transformation during growth on chitin, a biopolymer that is abundant in aquatic habitats (e.g., from crustacean exoskeletons), where it lives as an autochthonous microbe. Transformation competence was found to require a type IV pilus assembly complex, a putative DNA binding protein, and three convergent regulatory cascades, which are activated by chitin, increasing cell density, and nutrient limitation, a decline in growth rate, or stress. 相似文献
124.
Munir Iqbal Tahir Yaqub Nadia Mukhtar Muhammad Z Shabbir John W McCauley 《Veterinary research》2013,44(1):100
Genetic changes in avian influenza viruses influence their infectivity, virulence and transmission. Recently we identified a novel genotype of H9N2 viruses in widespread circulation in poultry in Pakistan that contained polymerases (PB2, PB1 and PA) and non-structural (NS) gene segments identical to highly pathogenic H7N3 viruses. Here, we investigated the potential of these viruses to cause disease and assessed the transmission capability of the virus within and between poultry and wild terrestrial avian species. Groups of broilers, layers, jungle fowl, quail, sparrows or crows were infected with a representative strain (A/chicken/UDL-01/08) of this H9N2 virus and then mixed with naïve birds of the same breed or species, or different species to examine transmission. With the exception of crows, all directly inoculated and contact birds showed clinical signs, varying in severity with quail showing the most pronounced clinical signs. Virus shedding was detected in all infected birds, with quail showing the greatest levels of virus secretion, but only very low levels of virus were found in directly infected crow samples. Efficient virus intra-species transmission was observed within each group with the exception of crows in which no evidence of transmission was seen. Interspecies transmission was examined between chickens and sparrows and vice versa and efficient transmission was seen in either direction. These results highlight the ease of spread of this group of H9N2 viruses between domesticated poultry and sparrows and show that sparrows need to be considered as a high risk species for transmitting H9N2 viruses between premises. 相似文献
125.
Arafa NM 《Pakistan journal of biological sciences: PJBS》2010,13(20):966-976
The study aimed to evaluate the effect Echinacea extract (E) on the testicular antioxidants function in normal rats or that subjected to anti-androgenic compound, cyproterone acetate (CA). Rats were divided into 5 groups treated daily via an oral tube for two intervals 2 and 4 weeks, 1st control, 2nd E (Echinacea treated group in dose 63 mg kg(-1)), 3rd CA (cyproterone acetate treated group in dose 25 mg kg(-1)), 4th E+CA and 5th E as prophylactic one week before E+CA treatment with the same aforementioned E or CA doses. The body, testes, epididymis and vas deferens weights were recorded. Sperm count, Nitric Oxide (NO), calcium ion (Ca2+) and malondialdhyde (MDA) contents in addition to superoxide dismutase (SOD), glutathione S-transferase (GST) activities were determined in testicular tissues. CA exhibited direct negative effect on reproductive organs weight and significant reducing effect on sperm count and Ca2+ contents. SOD and GST activities significantly decreased in addition to significant increase in NO, MDA contents reflecting the oxidative status of testis in CA treated rats. The prophylactic effect of E treatment, in time related manner, showed significant improvement in the antioxidant status of the testicular tissue which is more pronounced as compared to E+CA treatment. 相似文献
126.
Nadia Bertazzon Michele Borgo Stefano Vanin Elisa Angelini 《European journal of plant pathology / European Foundation for Plant Pathology》2010,127(2):185-197
The genetic variability among Grapevine leafroll-associated virus 2 (GLRaV-2) isolates was investigated in several grapevine accessions from various geographic origins in three genomic fragments,
which encode the 70 kDa heat-shock protein homologue, the coat protein and the ∼60 kDa protein. The majority of the isolates
were identical or only slightly different from one another and formed a monophyletic group. Several other variants were found
which differed greatly from the main cluster and were mostly present in autochthonous or specific vine cultivars. Phylogenetic
analyses on the CP gene sequences, including the isolates analyzed in this work and some others from related literature, allowed
five clades to be identified (PN, H4, RG, BD and PV20). Biological trials for graft incompatibility and leafroll symptoms
revealed that GLRaV-2 divergent variants had different pathological properties, mainly according to their phylogenetic grouping.
The BD isolate seemed to be a mild variant of the virus, because it was unable to induce graft incompatibility and it rarely
caused leafroll symptoms. The RG isolate appeared to be a more virulent variant, given the strong decrease in rooted grafted
grapevines obtained in nursery, in particular with the use of certain rootstocks; however, it does not induce leafroll symptoms.
The variants belonging to the PN group, which were the most widespread, caused both graft incompatibility and leafroll symptoms,
according to the viral variant. Graft incompatibility also proved to depend strongly on the rootstock used. 相似文献
127.
Guangling Jiao Joseph P. M. Hui Ian W. Burton Marie-Hélène Thibault Claude Pelletier Josée Boudreau Nadia Tchoukanova Balaji Subramanian Yahia Djaoued Stephen Ewart Jacques Gagnon Kathryn Vanya Ewart Junzeng Zhang 《Marine drugs》2015,13(6):3849-3876
Northern shrimp (Pandalus borealis) oil, which is rich in omega-3 fatty acids, was recovered from the cooking water of shrimp processing facilities. The oil contains significant amounts of omega-3 fatty acids in triglyceride form, along with substantial long-chain monounsaturated fatty acids (MUFAs). It also features natural isomeric forms of astaxanthin, a nutritional carotenoid, which gives the oil a brilliant red color. As part of our efforts in developing value added products from waste streams of the seafood processing industry, we present in this paper a comprehensive characterization of the triacylglycerols (TAGs) and astaxanthin esters that predominate in the shrimp oil by using HPLC-HRMS and MS/MS, as well as 13C-NMR. This approach, in combination with FAME analysis, offers direct characterization of fatty acid molecules in their intact forms, including the distribution of regioisomers in TAGs. The information is important for the standardization and quality control, as well as for differentiation of composition features of shrimp oil, which could be sold as an ingredient in health supplements and functional foods. 相似文献
128.
Foliar application of microdoses of sucrose to reduce codling moth Cydia pomonella L. (Lepidoptera: Tortricidae) damage to apple trees 下载免费PDF全文
129.
de Almeida NR Danelli MG da Silva LH Hagiwara MK Mazur C 《Journal of Feline Medicine and Surgery》2012,14(8):583-586
Peripheral blood smears of 1094 domestic cats were collected and tested by indirect immunofluorescence antibody assay for p27 antigen in cells to study the prevalence and risk factors for feline leukemia virus (FeLV) in the state of Rio de Janeiro. Sex, age, breed, outdoor access, neutering status, type of habitation (household, shelter, veterinary clinics and other places), number of household cats and clinical signs were registered on a form. Among the tested samples, 11.52% were positive. Risk factors for FeLV infection included outdoor access, age range between 1 and 5 years old, and cohabitation with numerous cats. 相似文献
130.