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591.
Identification of parasites in Puffinus puffinus (Birds, Procellariiformes) from Northeastern Brazil
Cristiane Maria Fernandes de Melo Jaqueline Bianque de Oliveira Ana Célia Rodrigues Athayde Ant?nio Flávio Medeiros Dantas Thais Ferreira Feitosa Vinícius Longo Ribeiro Vilela Danilo José Ayres de Menezes Paulo Guilherme Carniel Wagner 《Veterinary research communications》2012,36(4):235-238
Studies on the parasitic fauna of migratory sea birds of the Puffinus genus are scarce. Therefore, the aim of this study was to identify parasites of 16 specimens of Puffinus puffinus (Procellariiformes, Procellariidae) that died during the period of June 2011 to December 2011 at the Wildlife Screening Center (CETAS) of the Brazilian Institute of Environment and Natural Resources (IBAMA) in Cabedelo, Paraíba. During necropsy, biting lice and/or gastrointestinal helminths were collected in seven (43.7?%) birds. Lice were collected in five (31.2?%) birds, and the species identified were Halipeurus diversus, Trabeculus aviator, Austromenopon paululum), Saemundssonia sp. and Naubates sp. The prevalence of helminths was also 31.2?%. The nematodes species were Seuratia shipleyi and Contracaecum sp., and cestodes were Tetrabothrius sp. This is the first record in Brazil of Naubates sp., Seuratia shipleyi, Contracaecum sp., and Tetrabothrius sp. in Puffinus puffinus. 相似文献
592.
Veríssimo CJ Niciura SC Alberti AL Rodrigues CF Barbosa CM Chiebao DP Cardoso D da Silva GS Pereira JR Margatho LF da Costa RL Nardon RF Ueno TE Curci VC Molento MB 《Veterinary parasitology》2012,187(1-2):209-216
The economic importance of sheep production is increasing worldwide simultaneously with the emergence of parasitic resistance. This study aimed to survey the current situation of management practices and parasite resistance in sheep flocks in S?o Paulo state, Brazil. A questionnaire was given to 35 sheep farmers to obtain information related to flock management practices. Of these flocks, 30 were submitted to the fecal egg count reduction test (FECRT) with at least one of the five following anthelmintics: albendazole, closantel, ivermectin, levamisole, and moxidectin, for comparison against an untreated control group. In the survey, the median number animals per flock was 301, mainly of the Santa Ines breed (in 75.8% of the flocks) and crossbred animals (in 54.5% of the flocks). The predominant farming system was semi-intensive (82.9%), using rotational grazing (80%). Selective treatment was based on FAMACHA grade (47.1%) and in clinical signs (41.2%). The most often applied anthelmintics were macrocyclic lactones (42.9-54.2% in the last three applications). Considering the anthelmintics employed in this study, 10.7% of the farms' flocks were resistant to three, 35.7% to four, and 53.6% to all five anthelmintics. The main helminth genera observed before and after treatments were Haemonchus sp. (75.8%) and Trichostrongylus sp. (19.1%), but all observed genera (Cooperia sp., Oesophagostomum sp., and Strongyloides sp.) were detected by the FECRT. Considering efficacy values less than or equal to 90% in the FECRT as resistant, 100% of flocks were resistant to albendazole and ivermectin, 96.6% to moxidectin, 92.9% to closantel, and 53.6% to levamisole. It is thus possible to conclude that multidrug resistance is widespread in sheep flocks in S?o Paulo state, Brazil, and this involves all prevalent helminth genera. 相似文献
593.
Chlamydophila psittaci (C. psittaci) infection was evaluated in 77 free-living nestlings of Blue-fronted Amazon parrots (Amazona aestiva) and Hyacinth macaws (Anodorhynchus hyacinthinus) in the Pantanal of Mato Grosso do Sul, Brazil. Tracheal and cloacal swab samples from 32 wild parrot and 45 macaw nestlings were submitted to semi-nested PCR, while serum samples were submitted to complement fixation test (CFT). Although all 32 Amazon parrot serum samples were negative by CFT, cloacal swabs from two birds were positive for Chlamydophila DNA by semi-nested PCR (6.3%); these positive birds were 32 and 45 days old. In macaws, tracheal and cloacal swabs were positive in 8.9% and 26.7% of the samples, respectively. Complement-fixing antibodies were detected in 4.8% of the macaw nestlings; macaw nestlings with positive findings were between 33 and 88 days old. These results indicate widespread dissemination of this pathogen in the two evaluated psittacine populations. No birds had clinical signs suggestive of chlamydiosis. To the best of our knowledge, this is the first report on C. psittaci in free-living Blue-fronted Amazon parrots and Hyacinth macaws in Brazil. 相似文献
594.
Biological and molecular properties of Tomato rugose mosaic virus (ToRMV), a new tomato-infecting begomovirus from Brazil 总被引:1,自引:0,他引:1
J. J. Fernandes † M. G. Carvalho E. C. Andrade S. H. Brommonschenkel E. P. B. Fontes F. M. Zerbini 《Plant pathology》2006,55(4):513-522
A viral complex causing golden mosaic and leaf distortion (rugosity) in tomato plants was obtained from viruliferous whiteflies, and named TGV-Ub1. This complex was sap-transmitted from tomato to Nicotiana benthamiana . PCR amplification using universal begomovirus primers yielded two distinct fragments for DNA-A, suggesting that the TGV-Ub1 complex comprised at least two distinct viruses. Clones corresponding to full-length viral genomes were obtained from tomato plants infected with TGV-Ub1. Comparisons of the complete sequences of clones pUb1-49 (DNA-A), pUb1-62 and pUb1-81 (both DNA-B) indicated that they constitute novel western hemisphere begomoviruses. Clones pUb1-49 and pUB1-81 have identical common regions, thus representing the cognate DNA-A and -B of a novel begomovirus, named Tomato rugose mosaic virus (ToRMV). Clone pUb1-62 has a distinct common region from ToRMV and all other geminiviruses. A cognate DNA-A for pUb1-62 was not found. Clones containing 1·8 copies of the genomic components were constructed. Infectivity assays of these clones in tomato and N. benthamiana demonstrated that the clones corresponding to ToRMV systemically infected both hosts. Symptoms were analogous to those observed when using the pure isolates obtained in this study. The combination of pUb1-49 and -62 did not result in systemic infection, indicating that these components do not form a viable virus. ToRMV was sap-transmitted from N. benthamiana to N. benthamiana , and by grafting to Solanum tuberosum and Datura stramonium . ToRMV-A and ToRMV-B were detected in plants of Nicandra physaloides and Phaseolus vulgaris , respectively, growing in nearby tomato fields, in association with distinct DNA components. 相似文献
595.
M. Luisa Valdeira Catarina Bernardes B. Cruz A. Geraldes 《Veterinary microbiology》1998,60(2-4):131-140
African swine fever virus (ASFV) enters Vero cells by adsorptive endocytosis [Valdeira, M.L., Geraldes, A., 1985. Morphological study on the entry of African swine fever virus into cells, Biol. Cell. 55, 35–40]. Electron microscopy of a lysosomotropic drug-controlled penetration indicated that this step takes place in the endosomes, after fusion between the viral envelope and the limiting membrane of the endosome. Inhibition studies with colcemid, cytochalasin B, sodium azide, dinitrophenol, lysosomotropic weak bases, and the ionophore monensin, showed that the virus uptake is largely independent of cytoskeletal and lysosomal function, but dependent on oxidative phosphorylation. Some protease inhibitors inhibited viral replication at an early step, indicating that the initiation of infection depends on a viral proteolytic cleavage. 相似文献
596.
Diego Souza Buarque Patrícia Fernandes Castro Fábio Marcel Silva Santos Daniel Lemos Luiz Bezerra Carvalho Júnior & Ranilson Souza Bezerra 《Aquaculture Research》2009,40(7):861-870
Proteases from the midgut gland of the Farfantepenaeus paulensis juveniles were assessed. Enzyme activity was determined using protease substrates and inhibitors. The effect of pH, temperature and calcium on proteolytic activity was assayed. Caseinolytic activity was analysed in substrate-sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). Trypsin, chymotrypsin and leucine aminopeptidase activity was detected. Proteolytic activity was strongly inhibited by the specific trypsin inhibitors. Tosyl-phenylalanine chloromethyl ketone inhibited 59.3% of chymotrypsin activity. The greatest trypsin-like activity occurred at pH 8.0 and 45 °C. Chymotrypsin-like activity reached maximal values at alkaline pH (7.2–9.0) and 55 °C. CaCl2 did not increase trypsin-like activity, but rather inhibited it at concentrations of 30 (20%), 50 (30%) and 100 mM (50%). The substrate-SDS-PAGE zymogram revealed eight proteinase bands. Two possibly thermal-resistant (85 °C, 30 min) chymotrypsin isoforms were found, which were inhibited by phenyl-methyl-sulphonyl-fluoride. Aminopeptidase activity of enzyme extracts (Arg, Leu, Lys, Phe and Val) and the recommended concentrations of these essential amino acids in penaeid shrimp diets were positively correlated ( P <0.05). Beause protein digestion involves the combined action of different enzymes, adequate knowledge of shrimp digestion and enzyme characteristics is required for the assessment of the digestive potential of different feed sources and development of in vitro digestibility protocols. 相似文献
597.
Fabiano A. PETTER Tamara S. FERREIRA Adilson P. SINHORIN Larissa B. LIMA Fernandes A. ALMEIDA Leandro P. PACHECO Alexandre F. SILVA 《土壤圈》2019,29(6):801-809
The herbicide diuron is widely used in agricultural areas in Brazil, whereas it has high potential for subsurface water contamination due to its physicochemical characteristics. Recent studies have demonstrated the potential of biochar as a sorbent and possible pesticide leaching mitigation. The objective of this study was to investigate the long-term effect of biochar application on the kinetics of sorption and desorption of diuron in a Cerrado Haplic Plinthosol. Samples were collected in an experiment conducted in the field in a randomized block design consisting of the combination of two levels of fertilizer application (0 and 300 kg ha-1 of 5-25-15 formula of NPK fertilizers) and three doses of biochar (0, 16, and 32 Mg ha-1). The Freundlich isotherm accurately described the sorption of diuron in all treatments. Biochar application increased the sorption and reduced the desorption of diuron. This effect was attributed to the contribution of biochar to total organic carbon (C) and C in the humin fraction and to the increase in the reactivity of the humic acid and humin fractions, which was significantly highly correlated with the sorption coefficient (Kf). A positive correlation between the partition coefficient of organic C and Kf confirmed the importance of the soil organic compartment for the sorption of diuron. The higher diuron sorption and lower diuron desorption capacities of sandy soils after biochar application could reduce the potential risk of diuron leaching and contamination of subsurface water. 相似文献
598.
Caio Fábio Stoffel Efrom Luiza Rodrigues RedaelliRafael Narciso Meirelles Cláudia Bernardes Ourique 《Crop Protection》2011,30(9):1162-1167
The South American fruit fly, Anastrepha fraterculus (Wied.), is one of the principal pests of fruit crops in Brazil. While organic farms use several compounds to control fruit flies, such as oils, plant extracts and soaps, there is little scientific evidence of their effectiveness. Our main goal was to evaluate the phytosanitary products used in organic orchards on A. fraterculus under laboratory conditions. Four multiples (0.25×, 0.5×, 1× and 2×) of the manufacturer-recommended concentrations of Rotenat CE® (extract of Derris spp. with rotenone 5%) (600 ml 100 l−1), Pironat® (pyroligneous extract) (250 ml 100 l−1), Biopirol 7M® (pyroligneous extract) (200 ml 100 l−1), Organic neem® (neem oil 80%) (500 ml 100 l−1), Natuneem® (neem oil - 1500 ppm of azadirachtin) (500 ml 100 l−1) and lime sulfur (20% S + 9% Ca) (5000 ml 100 l−1) were tested on A. fraterculus via ingestion and direct contact, topical application and residual application. We subsequently tested deterrence effects of the same products on oviposition. Organic Neem®, Natuneem®, lime sulfur, Pironat®, and Biopirol 7M® showed no insecticidal effect on the South American fruit fly. Only Rotenat CE® (1200 ml 100 l−1) showed an effect (71.6% mortality) following ingestion/contact. Lime sulfur, Pironat® and Biopirol 7M® did not prevent oviposition of A. fraterculus on artificial fruits. 相似文献
599.
Gilberto Fernandes Marchioro Cécile Cornou Anders Ringgaard Kristensen Jan Madsen 《Computers and Electronics in Agriculture》2011,77(1):110-117
This paper discusses the main architectural alternatives and design decisions in order to implement a sows’ activity classification model on electronic devices. The different possibilities are analyzed in practical and technical aspects, focusing on the implementation metrics, like cost, performance, complexity and reliability. The target architectures are divided into: server based, where the main processing element is a central computer; and embedded based, where the processing is distributed on devices attached to the animals. The initial classification model identifies the activities performed by the sows using a multi-process Kalman filter having, as input, 3-axes data from accelerometers. However, the power demanding hardware resources to run the filters require frequent battery recharges, making its use unsuitable in the current state-of-the-art. It motivated the development of a heuristic classification approach, focusing on the resource constrained characteristics of embedded systems. The new approach classifies the activities performed by the sows with accuracy close to 90%. It was implemented as a hardware module that can easily be instantiated to provide preprocessed information to models in order to detect important situations in the sows’ life, e.g. the onset of farrowing. 相似文献
600.
BACKGROUND: In Brazil, dengue vector control is hampered by the resistance of Aedes aegypti L. populations to organophosphates (OPs). Insect growth regulators (IGRs) are a promising alternative, as their mechanisms of action are different from those of conventional insecticides. The authors analysed the effect of the IGR triflumuron, a chitin synthesis inhibitor, on the Ae. aegypti insecticide-susceptible strain Rockefeller, as well as on field populations both susceptible (TemS) and resistant (TemR) to the OP temephos. RESULTS: Triflumuron arrested development and inhibited adult emergence of the Rockefeller strain in a dose-dependent way (EI(50) and EI(90) of 0.8 and 1.8 microg L(-1) respectively). A direct relationship between triflumuron concentration and the precocity of its effects was evident. TemS and TemR temephos resistance ratios (RR(90)) were 4.5 and 13.8, triflumuron RR(90) being 1.0 and 1.3 respectively. CONCLUSION: The IGR triflumuron exhibited a dose-dependent effect against the reference Ae. aegypti Rockefeller strain. It was also effective against two field populations, regardless of their OP resistance status. The present results are discussed in the context of utilization of chitin synthesis inhibitors as potential alternatives in the control of Ae. aegypti in Brazil. 相似文献