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71.
Afonso SM Vaz Y Neves L Pondja A Dias G Willingham AL Vilhena M Duarte PC Jost CC Noormahomed EV 《Animal health research reviews / Conference of Research Workers in Animal Diseases》2011,12(1):123-129
The objective of this paper is to critically review and summarize available scientific and lay literature, and ongoing studies on human and porcine cysticercosis in Mozambique to identify knowledge gaps and direct immediate and long-term research efforts. Data on the spatial distribution and prevalence of the disease in human and swine populations are scarce and fragmented. Human serological studies have shown that 15-21% of apparently healthy adults were positive for cysticercosis antibodies or antigen, while in neuropsychiatric patients seroprevalence was as high as 51%. Slaughterhouse records indicate a countrywide occurrence of porcine cysticercosis, while studies have shown that 10-35% of pigs tested were seropositive for cysticercosis antibodies or antigen. Current research in Mozambique includes studies on the epidemiology, molecular biology, diagnosis and control of the disease. Future research efforts should be directed at better understanding the epidemiology of the disease in Mozambique, particularly risk factors for its occurrence and spread in human and swine populations, documenting the socio-economic impact of the disease, identifying critical control points and evaluating the feasibility and epidemiological impact of control measures and development of local level diagnostic tools for use in humans and swine. 相似文献
72.
73.
Fafetine JM Tijhaar E Paweska JT Neves LC Hendriks J Swanepoel R Coetzer JA Egberink HF Rutten VP 《Veterinary microbiology》2007,121(1-2):29-38
Serodiagnosis of Rift Valley fever (RVF) currently relies on the use of live or inactivated whole virus as antigens. The recombinant nucleocapsid (N) protein of RVF virus was tested for diagnostic applicability in an indirect enzyme-linked immunosorbent assay (I-ELISA), using sera from experimentally infected sheep (n=128), vaccinated sheep (n=240), and field-collected sera from sheep (n=251), goats (n=362) and cattle (n=100). The N-protein based I-ELISA performed at least as good as VN and HI tests. In goat the diagnostic sensitivity (D-Sn) and specificity (D-Sp) of the I-ELISA was 100% when using the anti-species IgG conjugate. Using protein G as a detection system, the D-Sn and D-Sp in goats were 99.4% and 99.5%, in sheep field sera both 100%, in cattle 100% and 98.3%, respectively. The I-ELISA based on recombinant N-protein has the potential to complement the traditional assays for serodiagnosis of RVF. Advantages of the N-protein are its safety, stability and cost-effectiveness in use and production. 相似文献
74.
Almeida FB Rodrigues-Silva R Neves RH Romani EL Machado-Silva JR 《Veterinary parasitology》2007,143(1):50-58
Echinococcus granulosus infection is a problem of public health in livestock-rearing regions of Latin America, like in Peru. This species is characterized by the morphometry of the large and small rostellar hooks in both metacestodes and adult worms. The aim of this work was to study biometrical characteristics of rostellar hooks in hydatid cysts (lung and liver) from some Peruvian provinces (Arequipa, Cuzco, Huancavelica, Junin and Puno). The biometrical analysis was obtained in a digital system for image analysis. The following parameters were studied: area, perimeter, length and width total of the handle, the blade and the distance between the blade and the guard of large and small hooks. For statistical analysis Student's t-test and Analysis of Variance (ANOVA) with Pos-test of Tukey were used, considering the values of p< or =0.05 as of statistic significance. All morphometric characters of large and small hooks were highly significant (p<0.000), when data were compared among the samples from the different provinces. Rostellar hooks in specimens from Huancavelica presented smallest measurements, whereas hooks in specimens from Junin were bigger in relation to the total and blade measurements. Generally, samples from Arequipa presented the biggest large hooks in relation to the handle parameters. The rostellar hooks of cattle and sheep hosts varied depending on the geographic localization, host and organ. Hooks recovered from the lungs were larger than those collected in the liver. It was concluded that morphometry using computer image analysis allows the characterization of E. granulosus. The rostellar hooks presented morphometric polymorphism. 相似文献
75.
A genomewide association mapping study using ultrasound‐scanned information identifies potential genomic regions and candidate genes affecting carcass traits in Nellore cattle 下载免费PDF全文
M.H.A. Santana R.V. Ventura Y.T. Utsunomiya H.H.R. Neves P.A. Alexandre G.A. Oliveira Junior R.C. Gomes M.N. Bonin L.L. Coutinho J.F. Garcia S.L. Silva H. Fukumasu P.R. Leme J.B.S. Ferraz 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2015,132(6):420-427
The aim of this study was to identify candidate genes and genomic regions associated with ultrasound‐derived measurements of the rib‐eye area (REA), backfat thickness (BFT) and rumpfat thickness (RFT) in Nellore cattle. Data from 640 Nellore steers and young bulls with genotypes for 290 863 single nucleotide polymorphisms (SNPs) were used for genomewide association mapping. Significant SNP associations were explored to find possible candidate genes related to physiological processes. Several of the significant markers detected were mapped onto functional candidate genes including ARFGAP3, CLSTN2 and DPYD for REA; OSBPL3 and SUDS3 for BFT; and RARRES1 and VEPH1 for RFT. The physiological pathway related to lipid metabolism (CLSTN2, OSBPL3, RARRES1 and VEPH1) was identified. The significant markers within previously reported QTLs reinforce the importance of the genomic regions, and the other loci offer candidate genes that have not been related to carcass traits in previous investigations. 相似文献
76.
Suppression of Saprolegnia infections in rainbow trout (Oncorhynchus mykiss) eggs using protective bacteria and ultraviolet irradiation of the hatchery water 下载免费PDF全文
Jouni Heikkinen Marja Tiirola Satu Maarit Mustonen Päivi Eskelinen Dina Navia‐Paldanius Atte von Wright 《Aquaculture Research》2016,47(3):925-939
Since formalin is widely used in prevention of Saprolegnia infections in salmonid fish hatcheries, there is a need for more environmentally safe treatment methods. Therefore, we screened 360 bacterial isolates against their ability to antagonize the growth of Saprolegnia parasitica hyphae in vitro, and best strains were selected according to their antagonistic properties and colonization capability on rainbow trout egg surface. Protective bacterial cultures of Pseudomonas sp. M162, Pseudomonas sp. M174 and Janthinobacterium M169 were tested for prevention of Saprolegnia sp. infections during incubation trials of rainbow trout (Oncorhynchus mykiss) eggs with UV irradiated (400 mWs cm?2) and non‐treated inlet water. UV irradiation of inlet water significantly decreased mortality during the incubation. Lowest mortalities were observed in protective culture treated groups incubated with UV‐irradiated inlet water. UV irradiation increased the dominance of the main bacterial colonizers and variation in the bacterial species diversity between the experimental units. 相似文献
77.
Sofia Cavaco Matthew K. Williamson Joana Rosa Vânia Roberto Odete Cordeiro Paul A. Price M. Leonor Cancela Vincent Laizé Dina C. Simes 《Fish physiology and biochemistry》2014,40(3):731-738
The occurrence of a second osteocalcin (OC2) has been reported in teleost fish, where it coexists with OC1 in some species. While it has been proposed that OC2 gene originated from OC1 through the fish whole-genome duplication event, little information is available on its molecular function and physiological role. The present study brings biological data supporting the presence of OC2 in the mineral phase of teleost fish bone and its association with the mineral phase together with OC1. The occurrence of OC2 forms with different levels of phosphorylation or γ-carboxylation, and with amino acid substitutions was observed. Comparative analysis of mature peptide sequences revealed the high conservation existing between OC1 and OC2, in particular within the core γ-carboxyglutamic acid domain, and suggests that both protein forms may have the same function, i.e., binding of calcium ions or hydroxyapatite crystals. 相似文献
78.
Eduardo Neves Costa Zulene Antônio Ribeiro Bruno Henrique Sardinha de Souza Arlindo Leal Boiça Júnior 《国际虫害防治杂志》2014,60(1):52-58
This study assessed current research methods and applied them to tests of oviposition preference by Diabrotica speciosa (Germar) for different soybean genotypes; the correlation between the number of eggs per plant and leaf intake was evaluated. The experiments were divided into four parts: (i) assessing the preferred oviposition substrate; (ii) standardizing the number of D. speciosa pairs, (iii) evaluating the preferred soybean plant age, and (iv) testing the preference for oviposition on different soybean genotypes, and evaluating its correlation with leaf intake under laboratory conditions. Females of D. speciosa preferred to lay eggs in the soil, with the highest number of eggs laid in the presence of a growing soybean plant. The genotypes PI 227687, DM 339, and PI 274454 were the least preferred varieties for oviposition, while BRSGO 8360 was the most preferred genotype. Egg counts were not correlated with leaf intake, except for the variety IGRA RA 626 RR, which showed positive correlation. Our discoveries may be helpful for second-crop use of resistant genotypes in areas where different crops are cultivated, by reducing the pest density off-season. 相似文献
79.
Mauricio Quesada G. Arturo Sanchez-Azofeifa Mariana Alvarez-Añorve Kathryn E. Stoner Luis Avila-Cabadilla Julio Calvo-Alvarado Alicia Castillo Mario M. Espírito-Santo Marcilio Fagundes Geraldo W. Fernandes John Gamon Martha Lopezaraiza-Mikel Deborah Lawrence Leonor Patricia Cerdeira Morellato Jennifer S. Powers Frederico de S. Neves Victor Rosas-Guerrero Roberto Sayago Gumersindo Sanchez-Montoya 《Forest Ecology and Management》2009
Understanding tropical forest succession is critical for the development of tropical forest conservation strategies worldwide, given that tropical secondary forests can be considered the forests of the future. Tropical dry forests (TDF) are among the most threatened tropical ecosystems, there are more secondary forests and forest restoration efforts that require a better understanding of successional processes. The main goal of this synthesis for this special issue on the ecology and management of tropical dry forests in the Americas is to present a summarized review of the current knowledge of the ecology and management implications associated to TDF succession. We explore specific issues associated to tropical dry forest succession with emphasis on the use of chronosequences, plant diversity and composition, plant phenology and remote sensing, pollination, and animal–plant interactions; all under the integrating umbrella of ecosystem succession. We also emphasize the need to conduct socio-ecological research to understand changes in land-use history and its effects on succession and forest regeneration of TDF. We close this paper with some thoughts and ideas associated with the strong need for an integrating dimension not considered until today: the role of cyberinfrastructure and eco-informatics as a tool to support sound conservation, management and understanding of TDF in the Americas. 相似文献
80.
Sarah Giovanna Montenegro Lima Marjorie Caroline Liberato Cavalcanti Freire Vernica da Silva Oliveira Carlo Solisio Attilio Converti dley Antonini Neves de Lima 《Marine drugs》2021,19(9)
Astaxanthin (AST) is a biomolecule known for its powerful antioxidant effect, which is considered of great importance in biochemical research and has great potential for application in cosmetics, as well as food products that are beneficial to human health and medicines. Unfortunately, its poor solubility in water, chemical instability, and low oral bioavailability make its applications in the cosmetic and pharmaceutical field a major challenge for the development of new products. To favor the search for alternatives to enhance and make possible the use of AST in formulations, this article aimed to review the scientific data on its application in delivery systems. The search was made in databases without time restriction, using keywords such as astaxanthin, delivery systems, skin, cosmetic, topical, and dermal. All delivery systems found, such as liposomes, particulate systems, inclusion complexes, emulsions, and films, presented peculiar advantages able to enhance AST properties, among which are stability, antioxidant potential, biological activities, and drug release. This survey showed that further studies are needed for the industrial development of new AST-containing cosmetics and topical formulations. 相似文献