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31.
We explored impacts of climate change on the geographic distribution of European beech by applying state of the art statistical and process-based models, and assessed possible climate change impacts on both adaptive capacity in the centre of its distribution and adaptive responses of functional traits at the leading and trailing edge of the current distribution. The species area models agree that beech has the potential to expand its northern edge and loose habitat at the southern edge of its distribution in a future climate. The change in local population size in the centre of the distribution of beech has a small effect on the genetic diversity of beech, which is projected to maintain its current population size or to increase in population size. Thus, an adaptive response of functional traits of small populations at the leading and trailing edges of the distribution is possible based on genetic diversity available in the local population, even within a period of 2–3 generations.  相似文献   
32.
Glycoprotein B (gB) of bovine herpesvirus 1 (BHV-1), a major component of the viral envelope, is essential for membrane fusion during entry and cell-to-cell spread. It is cleaved in the trans-Golgi network by the proprotein convertase furin. Integration of the open reading frame (ORF) encoding a mutated gB with a second furin cleavage site and mature boIFN-α as intervening peptide between the amino-terminal (NH2) and carboxy-terminal (COOH) gB subunits yielded recombinant BHV-1/gB2FuIFN-α which, unexpectedly, express gB with an enlarged NH2-subunit of 90 kDa. Here we show that boIFN-α-specific antibodies bind to the 90 kDa gB subunit and efficiently neutralize BHV-1/gB2FuIN-α infectivity. We also show that inactivated BHV-1/gB2FuIN-α virions induce an antiviral state in cells incubated with UV-inactivated particles. These results demonstrate that the 90 kDa protein is a NH2-subunit/boIFN-α fusion protein whose boIFN-α domain is biologically active. To verify that BHV-1 gB is suitable for the display of (glyco)proteins on the surface of virions we constructed BHV-1 recombinants expressing within gB the first 273 amino acids of the NH2-subunit (HA1) of avian influenza haemagglutinin, either flanked by two furin cleavage sites or with only one cleavage site between a gB/NH2_HA1 fusion protein and the COOH subunit. The resulting recombinant BHV-1/gB2FuHA1 expressed gB from which 55 kDa HA1 was excised and secreted. In contrast, gB from BHV-1/gB_NH2HA1 infected cells retained HA1 as fusion protein with the NH2-subunit. Immunoblotting and neutralization analyses revealed that HA1 is incorporated into the envelope BHV-1/gB/NH2_HA1 particles and exposed to the exterior of virions. Thus, this novel approach enables display of polypeptides and (glyco)proteins of at least 273 amino acids on viral particles which is of particular interest for development of novel diagnostics and vaccines as well as for, e.g. gene therapy applications especially when biologically active ligands need to be presented.  相似文献   
33.
Die Bewertung von Bodenfunktionen in Mooren ist derzeitig aufgrund fehlender Bewertungsmethoden als auch Bewertungsparameter nur unbefriedigend möglich. Das Ziel der Forschungsarbeit war die Erarbeitung einer Methode, vorhandene Altdaten für die Kennzeichnung von Flächenbodenformen in Bodenkarten so aufzubereiten, dass Idealprofile mit entsprechenden Datensätzen für die Bewertung von Bodenfunktionen bereitgestellt werden können. Zur Auswertung kamen folgende Materialien: Datensätze von verschiedenen hydrologisch‐genetischen Moortypen mit Informationen zur Stratigraphie, Art der Torfe und Mudden, Zersetzungsgrad, Tiefe der Substratwechsel, wesentliche physikalische und hydrologische Bodenkennwerte sowie digitalisierte Bodenkarten 1:25000. Die entwickelte Methode stellt eine Abfolgevorschrift mit Zuordnungsregeln dar. Informationen über den hydrologisch‐genetischen Moortyp und die Art der liegenden Schicht ermöglichen eine Vorhersage des Bodensubtyps. Zwei Stufen der Bodenentwicklung wurden beschrieben: vererdetes und vermulmtes Niedermoor. Unter Verwendung von Verknüpfungsregeln und Expertwissen ist es möglich, Idealprofile für Flächenbodenformen inhaltlich zu beschreiben. Durch Zuordnung von GIS‐Karten können dann Bodenfunktionen für definierte Flächen bewertet werden.  相似文献   
34.
Plant growth, reproduction, and biomass allocation may be affected differently by nitrogen availability depending on tree size and age. In this context, competition for limited N may be avoided by different strategies of N acquisition between different vegetation components (i.e., seedlings, mature trees, other woody and herbaceous understorey). This study investigated in a field experiment whether the competition for N between different vegetation components in beech forests was prevented via seasonal timing of N uptake and affected by microbial N use. For this purpose, a removal approach was used to study the seasonal effects on N uptake and N metabolites in adult beech trees and beech natural regeneration, as well as soil microbial processes of inorganic N production and utilisation. We found that the competition for N between beech natural regeneration and mature beech trees was reduced by seasonal avoidance strategies (“good parenting”) of N uptake regardless of the N sources used. In spring, organic and inorganic N uptake capacity was significantly higher in beech seedlings compared to adult beech trees, whereas in autumn mature beech trees showed the highest N uptake rates. Removal of vegetation components did not result in changes in soil microbial N processes in the course of the growing season. Thus, N resources released by the removal of vegetation components were marginal. This consistency in soil microbial N processes indicates that competition between plants and soil microorganisms for N was not avoided by timing of acquisition during the vegetation period, but existed during the entire growing season. In conclusion, N nutrition in the studied forest ecosystem seems to be optimally attuned to European beech.  相似文献   
35.
The goal of the present study was to investigate whether new PCR-methods would improve diagnostic of R. equi. In a first step, sensitivity and specificity of the PCR-methods in respect to the"gold standard" microbiological culture were determined. Secondly, sensitivity and specificity of both microbiological methods were evaluated in respect to the clinical diagnosis. The tracheobronchial secretions of 48 foals with pulmonary abscesses and of 37 healthy foals were evaluated by bacteriological culture as well as by four PCR-methods: aceA-, ideR-, vapA- and VP-PCR. In respect to the"gold standard" microbiological culture, the sensitivity of most PCR methods lay between 63.9 and 69.4 % except the vapA-PCR (27.8 %).The specificity of all PCR methods in this comparison was between 98 to 100 %. In this analysis, clinical diagnosis had a low sensitivity (66.7 %) and a low specificity (51.0 %). In respect to the clinical diagnosis, microbiological culture sensitivity was 50.0 % and specificity 67.7 9%. In this analysis, sensitivity rates of aceA-, ideR and VP-PCR methods lay between 33.3 and 37.5 %, sensitivity of the vapA-PCR was lower (10.4 %).The specificity of all PCR methods ranged from 78.4 to 86.5 %. In conclusion, these results show that the diagnostic potential of the microbiological methods"Culture" and "PCR" is different and that for the diagnosis of R. equi-pneumonia in foals the combination of microbiological culture with PCR should be used for examination of samples of the airways of foals.  相似文献   
36.
During a 6-year period, primary (idiopathic) immune-mediated thrombocytopenia was retrospectively evaluated in 30 dogs. Ages of the dogs ranged from 3 months to 10 years (median 4 years); female dogs were markedly overrepresented with 73%. Clinical examination revealed hemorrhages in 70% of the dogs. Platelet counts ranged from 0 to 111,000/microL (median 8000/microL); 77% of the dogs had platelet counts <30,000/microL. Seventeen dogs were anemic (hematocrit 9% to 36%; median 31%). Immunosuppressive therapy was performed in all but one dog. The recurrence rate of 19 dogs that were followed over an extended period (112 to 1684 days; median 340 days) was 26%. Twenty-nine (97%) dogs survived 14 days after initial presentation, and 27 (93%) dogs survived at least the following 15 to 1684 days (median 220 days).  相似文献   
37.
Isolation and molecular characterisation of equine rotaviruses from Germany   总被引:2,自引:0,他引:2  
A total of 26 rotavirus positive faecal samples of diarrhoeal foals, and 8 equine rotavirus isolates were examined. Viral RNA patterns were generated, G typing was performed by PCR, and a P[12]-specific DNA probe was developed for P typing. Furthermore, five equine rotavirus isolates were sequenced in the genomic regions coding for VP7 and part of VP4. Rotaviruses of genotype G3 P[12] were found in 22 faecal samples and G14 P[12] type could be found in 4 faecal samples. These findings confirm that in Germany G3 P[12] is the predominating type of equine rotaviruses.  相似文献   
38.
To help in the control of fowl plague caused by highly pathogenic avian influenza A viruses of hemagglutinin (HA) subtypes H5 and H7 several vaccines have been developed. A prophylactic immunization of poultry with inactivated influenza viruses in non-endemic situations is questionable, however, due to the impairment of serological identification of field virus-infected animals which hinders elimination of the infectious agent from the population. This problem might be overcome by the use of genetically engineered marker vaccines which contain only the protective influenza virus hemagglutinin. Infected animals could then be unambiguously identified by their serum antibodies against other influenza virus proteins, e.g. neuraminidase or nucleoprotein. For such a use, purified HA or HA-expressing DNA vaccines are conceivable. Economically advantageous and easier to apply are modified live virus vaccines in use against other poultry diseases, which have been modified to express influenza virus HA. So far, recombinant HA-expressing fowlpox virus (FPV) as well as infectious laryngotracheitis and Newcastle disease viruses have been asssessed in animal experiments. An H5-expressing FPV recombinant is already in use in Central America and Southeast Asia but without accompanying marker diagnostics. Advantages and disadvantages of the different viral vectors are discussed.  相似文献   
39.
BACKGROUND: Pinoxaden is a new cereal herbicide that provides outstanding levels of post‐emergence activity against a broad spectrum of grass weed species for worldwide selective use in both wheat and barley. RESULTS: Factors influencing activity and tolerance to pinoxaden were in part linked to distinct structural parts of the active ingredient. Three complementary contributions that decisively impact upon the herbicidal potency against grasses were identified: a preferred 2,6‐diethyl‐4‐methyl aromatic substitution pattern, a dione area suitable for proherbicide formation and beneficial adjuvant effects. The uptake and translocation pattern of pinoxaden when coapplied with its tailored adjuvant were analysed by autoradiography, indicating extensive and rapid penetration, followed by effective distribution throughout the plant. Crop injury reduction on incorporation of the [1,4,5]oxadiazepane ring into the aryldione template was reinforced with safener technology. Comparative studies on the behaviour of pinoxaden applied either alone or in combination with the safener cloquintocet‐mexyl demonstrated that addition of the safener resulted in significant enhancement of metabolic degradation in wheat and barley, providing excellent crop tolerance and a substantial selectivity margin without adverse effects on weed control. CONCLUSION: The biological potential of pinoxaden and its active principle pinoxaden dione in terms of grass weed control and tolerance in cereals was fully exploited by inclusion of the safener cloquintocet‐mexyl in the formulation in combination with a specific and tailor‐made tank‐mix adjuvant based on methylated rape seed oil. Copyright © 2011 Society of Chemical Industry  相似文献   
40.
Analysis for sixteen types of Polycyclic Aromatic hydrocarbons (PAHs)from samples of raw and treated wastewater, sediments, sludge andplants growing along treated wastewater way was performed inOctober 1997. The collection sites represent two wastewatertreatment plants (WWTP) receiving different types of wastewaterand one site from disposal of raw wastewater in the city ofKarak in southern Jordan.Wastewater treatment efficiency showed removal of PAHs throughsettling tanks and adsorption on sediments after treatment. Theremoval percentage ranged from 44–100% for individual PAH.PAHs were widely distributed at various levels in rawwastewater, treated wastewater, sludge, sediments and plants.The highest concentration was observed in sludge and the lowestin plants. There was a variation in PAHs concentration betweenthe three investigated sites which was attributed to theefficiency of treatment, period of contact with the wastewater,and the nature of activities. The WWTPs were capable or reducingPAHs contamination in water, up to 40% of the total PAHs byadsorption on sludge and sediments.  相似文献   
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