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91.
Two synthetic routes to 2-aryl-1,2,3-triazoles are outlined. These have been used to synthesise a wide range of compounds of this structural type. Their insecticidal activities were evaluated against a number of veterinary and public health pests. The activity of these compounds is especially good against the housefly (Musca domestica). Structure–activity relationships are discussed particularly in relation to the physical properties of the compounds.  相似文献   
92.
Deodorization of swine manure using minced horseradish roots and peroxides   总被引:1,自引:0,他引:1  
Public concerns about offensive odors from livestock manures are on the rise and so is the pressure to develop practical ways to reduce the odors. The use of minced horseradish (Armoracia rusticanaL) roots (1:10 w/v plant tissue to swine slurry ratio), with calcium peroxide (CaO2 at 26 or 34 mM) or hydrogen peroxide (H2O2 at 34, 52, or 68 mM) for the deodorization of swine manure, was evaluated through a series of laboratory experiments. The principle underlying this deodorization method is the oxidation of odorants by the concerted action of horseradish peroxidase (present in the plant tissue) and peroxide that serves as an electron acceptor, followed by polymerization of phenolic odorants with a possible copolymerization or adsorption of other odorant compounds. The deodorization effect was assessed by a human panel and gas chromatography (GC). In the case of the GC method, 12 compounds commonly associated with malodor (7 volatile fatty acids or VFAs, 3 phenolic compounds, and 2 indolic compounds) were used as odor indicators. Malodor assessment of the treated slurry by a human panel indicated a 50% reduction in odor intensity. GC results showed 100% removal of all phenolic odorants without reoccurrence for at least 72 h. In view of these data, using plant materials as enzyme carriers and peroxides as electron acceptors emerges as an effective approach to phenolic odor control in animal manure.  相似文献   
93.
Pastoral herders in Madagascar have limited access to animal health workers and veterinary medicines, and more information on their livestock diseases is needed, so that effective animal health programmes can be implemented. In this study, participatory epidemiology methods were used to gather such information in the Mandrare Valley. These included pair-wise ranking and matrix scoring. Eleven diseases were deemed to be priorities by pair-wise ranking. Matrix scoring and characterisation showed that the informant groups associated many disease syndromes with the same diseases, indicating agreement and understanding of the key diseases. The Malagasy-named syndromes, Soko, Besorko and Mamany lio, which are gastrointestinal parasitism, clostridial disease and babesiosis, respectively, were identified by every informant group. A greater sample size may be needed to characterise the diseases precisely with matrix scoring because, in this study, the matrices’ scores had wide confidence intervals.  相似文献   
94.
95.
Foy E  Li K  Wang C  Sumpter R  Ikeda M  Lemon SM  Gale M 《Science (New York, N.Y.)》2003,300(5622):1145-1148
Persistent infections with hepatitis C virus (HCV) are likely to depend on viral inhibition of host defenses. We show that the HCV NS3/4A serine protease blocks the phosphorylation and effector action of interferon regulatory factor-3 (IRF-3), a key cellular antiviral signaling molecule. Disruption of NS3/4A protease function by mutation or a ketoamide peptidomimetic inhibitor relieved this blockade and restored IRF-3 phosphorylation after cellular challenge with an unrelated virus. Furthermore, dominant-negative or constitutively active IRF-3 mutants, respectively, enhanced or suppressed HCV RNA replication in hepatoma cells. Thus, the NS3/4A protease represents a dual therapeutic target, the inhibition of which may both block viral replication and restore IRF-3 control of HCV infection.  相似文献   
96.
Most explanations of the increase in life expectancy at older ages over history emphasize the importance of medical and public health factors of a particular historical period. We propose that the reduction in lifetime exposure to infectious diseases and other sources of inflammation--a cohort mechanism--has also made an important contribution to the historical decline in old-age mortality. Analysis of birth cohorts across the life-span since 1751 in Sweden reveals strong associations between early-age mortality and subsequent mortality in the same cohorts. We propose that a "cohort morbidity phenotype" represents inflammatory processes that persist from early age into adult life.  相似文献   
97.
The vapors of citral, its isomers geranial and neral, and its related compounds were examined for their effect on Penicillium digitatum, Penicillium italicum, and Geotrichum candidum, the major fungi responsible for postharvest spoilage of citrus. Vapor of citral and its two isomers generated from 15 microL L(-1) aqueous solutions in Petri dishes inhibited development of the three pathogens, with concentrations of 2-6 microL L(-1) also being effective against P. italicum. Vapors of citral and geranial from 15 microL L(-1) solutions were fungicidal to P. digitatum and G. candidum, while neral was fungicidal to G. candidum. Citral-related compounds were much less effective, with effectiveness decreasing from citronellal to citronellol and citronellic acid. R and S isomers of these three citral-related compounds generally had similar effects on the fungi tested.  相似文献   
98.
Objective: To identify and describe the physical, historical, and clinicopathologic characteristics of diseases requiring emergency treatment in postpartum mares, and to evaluate the utility of these characteristics in making an accurate diagnosis in these mares. Design: Retrospective study. Setting: University large animal hospital. Animals: One hundred and sixty‐three mares admitted for emergency treatment within 30 days following parturition between the years 1992 and 2002. Interventions: None. Measurements and main results: Information obtained from the medical records included age, breed, date of admission, sex of the foal from this parturition, time from parturition to admission, duration of clinical signs prior to admission, and any report of dystocia or normal attended delivery, physical examination and clinicopathologic findings and diagnosis. Urogenital hemorrhage and large colon volvulus were the most common diagnoses, comprising 16.6% and 15.9% of total cases, respectively. Older mares were more likely to have a diagnosis of urogenital hemorrhage than younger mares. Mares with urogenital hemorrhage had a median age of 13 years and were admitted to the hospital significantly closer to parturition than mares with other diagnoses. Anemia, hypoproteinemia, and hypofibrinogenemia were significantly associated with a diagnosis of urogenital hemorrhage and occurred in 32%, 36%, and 26% of the mares with urogenital hemorrhage, respectively. Dystocia was more commonly reported (70%) in mares with metritis. Leukopenia was more common (88%) in mares with uterine tears. Conclusions: Careful evaluation of clinicopathologic data can aid the emergency clinician in making a correct diagnosis in postpartum mares with emergent problems.  相似文献   
99.
Acute toxicity of chelated copper to juvenile red drum (x?= 3.1 g) was determined in a static test at 25 C and 8 ppt salinity. The 12, 24, 48, 72, and 96 h LC50s were 1.90, 0.84, 0.75, 0.64, and 0.52 mg/L copper, respectively. Effects of temperature and salinity on the 96 h LC50 (0.5 mg/L copper) for juvenile red drum (x?= 5.0 g) were tested at two temperatures, 25 and 30 C, and three salinities, 0.5, 8, and 30 ppt. Temperature significantly affected mortality; mortality in 0.5 and 8 ppt salinities was significantly higher at 30 C than at 25 C. An increase in salinity significantly reduced the mortality of juvenile red drum. Total mortality occurred in 0.5 ppt salinity within 48 h at 25 C and within 12 h at 30 C. Total mortality occurred in 8 ppt salinity within 72 h at 25 C and within 48 h at 30 C. No mortality occurred during 96 h in 30 ppt salinity at 25 C or 30 C.  相似文献   
100.
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