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排序方式: 共有280条查询结果,搜索用时 15 毫秒
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Altman S Bassler BL Beckwith J Belfort M Berg HC Bloom B Brenchley JE Campbell A Collier RJ Connell N Cozzarelli NR Craig NL Darst S Ebright RH Elledge SJ Falkow S Galan JE Gottesman M Gourse R Grindley ND Gross CA Grossman A Hochschild A Howe M Hurwitz J Isberg RR Kaplan S Kornberg A Kustu SG Landick RC Landy A Levy SB Losick R Long SR Maloy SR Mekalanos JJ Neidhardt FC Pace NR Ptashne M Roberts JW Roth JR Rothman-Denes LB Salyers A Schaechter M Shapiro L Silhavy TJ Simon MI Walker G 《Science (New York, N.Y.)》2005,307(5714):1409-1410
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Miller C Bielefeldt-Ohmann H MacMillan M Huitron-Resendiz S Henriksen S Elder J VandeWoude S 《Veterinary immunology and immunopathology》2011,143(3-4):282-291
Feline immunodeficiency virus (FIV) is a naturally occurring lentivirus of domestic cats, and is the causative agent of feline AIDS. Similar to human immunodeficiency virus (HIV), the pathogenesis of FIV involves infection of lymphocytes and macrophages, and results in chronic progressive immune system collapse and death. Neuropathologic correlates of FIV infection have not yet been elucidated, and may be relevant to understanding HIV-associated neurologic disease (neuroAIDS). As in HIV, FIV strains have been shown to express differential tendencies towards development of clinical neuroAIDS. To interrogate viral genetic determinants that might contribute to neuropathogenicity, cats were exposed to two well-characterized FIV strains with divergent clinical phenotypes and a chimeric strain as follows: FIV(PPR) (PPR, relatively apathogenic but associated with neurologic manifestations), FIV(C36) (C36, immunopathogenic but without associated neurologic disease), and Pcenv (a chimeric virus consisting of a PPR backbone with substituted C36 env region). A sham inoculum control group was also included. Peripheral nerve conduction velocity, CNS imaging studies, viral loads and hematologic analysis were performed over a 12 month period. At termination of the study (350 days post-inoculation), brain sections were obtained from four anatomic locations known to be involved in human and primate lentiviral neuroAIDS. Histological and immunohistochemical evaluation with seven markers of inflammation revealed that Pcenv infection resulted in mild inflammation of the CNS, microglial activation, neuronal degeneration and apoptosis, while C36 and PPR strains induced minimal neuropathologic changes. Conduction velocity aberrations were noted peripherally in all three groups at 63 weeks post-infection. Pcenv viral load in this study was intermediate to the parental strains (C36 demonstrating the highest viral load and PPR the lowest). These results collectively suggest that (i) 3' C36 genomic elements contribute to viral replication characteristics, and (ii) 5' PPR genomic elements contribute to CNS manifestations. This study illustrates the potential for FIV to provide valuable information about neuroAIDS pathogenesis related to genotype and viral kinetics, as well as to identify strains useful to evaluation of therapeutic intervention. 相似文献
135.
Diack AB Gladney CD Mellencamp MA Stear MJ Eckersall PD 《Veterinary immunology and immunopathology》2011,139(2-4):107-112
Acute phase proteins (APP) are used as markers of inflammation and sub-clinical disease and are considered potential biomarkers for pig health and welfare. However, reference ranges for their baseline concentrations are necessary before their use can be considered in routine herd health. In this study, C-reactive protein (CRP), haptoglobin (Hp), pig-major acute-phase protein (Pig-MAP) and transthyretin (TTR) baseline concentrations were determined in boars from a high health commercial herd and differences between seven commercial breeding lines within the herd were investigated. Reference ranges of 3.6-183 mg/L for CRP, 0.01-1.31 g/L for Hp, 0.32-2.9 g/L for Pig-MAP and 174-610 mg/L for TTR were found. Correlations were determined between Hp and CRP, Hp and Pig-MAP and CRP and Pig-MAP. Additionally, significant differences were found among the concentrations of CRP, Pig-MAP and TTR in seven commercial breeding lines. 相似文献
136.
Ponce-Macotela M Rodríguez-Caballero A Peralta-Abarca GE Martínez-Gordillo MN 《Veterinary parasitology》2011,175(3-4):382-385
Human toxocariasis causes several dangerous syndromes that can involve the viscera, vision and central nervous system. Diagnosing toxocariasis requires the identification of antibodies against Toxocara canis or Toxocara cati excretions and secretions (ES). To obtain ES it is necessary to collect a large number of larvae. However, since the earliest work describing the culture of Toxocara larvae, few advances in the method have been made. It has been suggested that carbon dioxide triggers molecular mechanisms that enable nematode hatching. A similar hypothesis has been made regarding Giardia excystation. To test the hypothesis we used the Giardia excystation HBSS method to hatch embryonated T. canis eggs. We found that the HBSS method was more effective than the original De Savigny method. Our results suggest that both parasites require stimulation in an acidic environment, and the abrupt change to a basic milieu in duodenum. This physiological adaptation is successful to exploit the intestinal habitat. 相似文献
137.
A B cell-based sensor for rapid identification of pathogens 总被引:1,自引:0,他引:1
Rider TH Petrovick MS Nargi FE Harper JD Schwoebel ED Mathews RH Blanchard DJ Bortolin LT Young AM Chen J Hollis MA 《Science (New York, N.Y.)》2003,301(5630):213-215
We report the use of genetically engineered cells in a pathogen identification sensor. This sensor uses B lymphocytes that have been engineered to emit light within seconds of exposure to specific bacteria and viruses. We demonstrated rapid screening of relevant samples and identification of a variety of pathogens at very low levels. Because of its speed, sensitivity, and specificity, this pathogen identification technology could prove useful for medical diagnostics, biowarfare defense, food- and water-quality monitoring, and other applications. 相似文献
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Sánchez-Andica Rubén Albeiro Chamorro-Rengifo Andrés Felipe Páez-Melo Martha Isabel 《Water, air, and soil pollution》2021,232(10):1-11
Water, Air, & Soil Pollution - The article presents the results of the study of sulfur-containing gases (carbon disulfide, CS2, and dimethyl sulfide, C2H6S) in the air above the sulfide... 相似文献