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11.
12.
Zimmerman AD Buterbaugh RE Herbert JM Hass JM Frank NE Luempert Iii LG Chase CC 《Journal of the American Veterinary Medical Association》2007,231(9):1386-1389
OBJECTIVE: To evaluate the efficacy of an inactivated bovine herpesvirus-1 (BHV-1) vaccine to protect against BHV-1 challenge-induced abortion and stillbirth. DESIGN: Prospective study. ANIMALS: 35 beef heifers. PROCEDURES: Before breeding, heifers were vaccinated with a commercially available BHV-1 inactivated vaccine SC or IM. The estrous cycle was then synchronized, and heifers were artificially inseminated 30 to 60 days after vaccination. Heifers (n = 21) were challenge inoculated IV at approximately 180 days of gestation with virulent BHV-1. Fourteen control heifers were not vaccinated. Clinical signs of BHV-1 infection were monitored for 10 days following challenge; serologic status and occurrence of abortion or stillbirth were evaluated until time of calving. RESULTS: 18 of 21 (85.7%) heifers that received vaccine were protected from abortion following challenge, whereas all 14 control heifers aborted. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that an inactivated BHV-1 vaccine can protect against abortion resulting from a substantial challenge infection, with efficacy similar to that of modified-live BHV-1 vaccines. 相似文献
13.
Cholera toxin promotes the generation of semi-mature porcine monocyte-derived dendritic cells that are unable to stimulate T cells 总被引:2,自引:0,他引:2
Bimczok D Rau H Wundrack N Naumann M Rothkötter HJ McCullough K Summerfield A 《Veterinary research》2007,38(4):597-612
Cholera toxin (Ctx) is a powerful mucosal adjuvant with potential applications for oral vaccination of swine. Dendritic cells (DC) play a key role in the decision between immunity and tolerance, and are likely target cells for mediating Ctx functions in vivo. Therefore, we examined the capacity of Ctx to enhance stimulatory activity of porcine monocyte-derived DC (MoDC). Ctx promoted the development of a semi-mature DC phenotype, with decreased levels of MHC class II and CD40, but increased CD80/86 expression. These changes were associated with activation of extracellular signal-regulated kinase (ERK), but not NFkappaB or c-Jun N-terminal kinase (JNK). Functionally, Ctx-priming greatly diminished T cell stimulatory capacity both in antigen-specific and superantigen-induced proliferation assays. The lower proliferation rate was not due to increased apoptosis of either DC or T cells. Ctx suppressed TNFalpha secretion by MoDC, but induced IL-10 production. The observed effects on T cell proliferation could only be partially mimicked by IL-10 alone. However, addition of recombinant TNFalpha to co-cultures of Ctx-primed MoDC and lymphocytes restored lymphocyte proliferation in a concentration-dependent manner. Ctx-primed DC were not actively tolerogenic, since they could not suppress proliferative T cell reactions induced by untreated DC. 相似文献
14.
Landscape Ecology - Pollinator declines and functional homogenization of farmland insect communities have been reported. Mass-flowering crops (MFC) can support pollinators by providing floral... 相似文献
15.
Dynamic oxygen mapping in the root zone by fluorescence dye imaging combined with neutron radiography 总被引:1,自引:0,他引:1
Nicole Rudolph Hanna G. Esser Andrea Carminati Ahmad B. Moradi André Hilger Nikolay Kardjilov Stefan Nagl Sascha E. Oswald 《Journal of Soils and Sediments》2012,12(1):63-74
Purpose
The rooted zone of a soil, more precisely the rhizosphere, is a very dynamic system. Some of the key processes are water uptake and root respiration. We have developed a novel method for measuring the real-time distribution of water and oxygen concentration in the rhizosphere as a biogeochemical interface in soil. This enables understanding where and when roots are active in respect to root respiration and water uptake and how the soil responds to it. 相似文献16.
García-González DL Barie N Rapp M Aparicio R 《Journal of agricultural and food chemistry》2004,52(25):7475-7479
A novel electronic nose based on solid-phase microextraction (SPME) coupled with a surface acoustic wave (SAW) sensor array has been used to analyze different quality virgin olive oils. A mathematical model was designed with 37 samples to distinguish lampante from the other virgin olive oils categories (extra-virgin and virgin), because lampante-virgin olive oils cannot be consumed without a previous refining process. The model, successfully validated with a test set of 16 samples, was able to classify 90% of the samples correctly. Misclassifications were explained by SPME-HRGC analyses and a second sensory evaluation. 相似文献
17.
Jégou S Douliez JP Mollé D Boivin P Marion D 《Journal of agricultural and food chemistry》2001,49(10):4942-4949
The influence of malting and brewing processes on the chemical and structural modifications occurring on LTP1 was investigated by mass spectrometry and circular dichroism. Proteins were first purified from malt, and samples were collected at various steps of beer processing performed on two barley cultivars. The levels of LTP1 found in malt were not significantly different from the amounts in barley seed. However, in malt, both LTP1b, a post-translational form of LTP1, and a third isoform named LTP1c were isolated. Moreover, both of these proteins were found to be heterogeneously glycated but still exhibited an alpha-helix structure. Both glycated LTP1 and LTP1b were recovered during mashing. It was also shown that glycated LTP1 was unfolded during heat treatment of wort boiling, which is in agreement with the denatured form previously isolated from beer. 相似文献
18.
Nicole?WellbrockEmail author Winfried?Riek Barbara?Wolff 《European Journal of Forest Research》2005,124(4):261-271
Based on the results of the atmospheric deposition classification of the year 1989, a methodical approach should be introduced,
which—based on the modelled total deposition rates—enables us to characterise the input situation of forest monitoring plots
and to delimit load areas in Germany. In 1989, the deposition situation in nearly 1,800 forest monitoring sites (BZE/extensive
Soil Condition Inventory) in Germany could be explained by four factors (or three, excluding sea salt impact) with the help
of a factor analysis. The factor values were grouped into six deposition types with typical compounds and regional patterns.
The classified input rates of the soil inventory plots adequately represent the stress situation and deposition changes in
Germany. The application of the statistical approach on the level of Brandenburg clarifies the special local input situation.
Due to the special combination of deposed elements, the sources of emissions can be characterised as well. When the soil inventory
is repeated, a project planned for 2006, this approach can be used in order to determine homogenous areas for stratified data
evaluation. 相似文献
19.
Sabine Augustin Jan Evers Hans-Peter Dietrich Johannes Eichhorn Thomas Haussmann Regina Icke Ansgar Isenberg Wolfgang Lux Monica Musio Hans Pretzsch Winfried Riek Thomas Rötzer Bernd Schultze Andreas Schulze Jörg Schröder Walter Seidling Nicole Wellbrock Klaus von Wilpert Barbara Wolff 《European Journal of Forest Research》2005,124(4):251-260
In the 1970s unexpected forest damages, called “new type of forest damage” or “forest decline”, were observed in Germany and
other European countries. The Federal Republic of Germany and the German Federal States implemented a forest monitoring system
in the early 1980s, in order to monitor and assess the forest condition. Due to the growing public awareness of possible adverse
effects of air pollution on forests, in 1985 the ICP Forests was launched under the convention on long-range transboundary
air pollution (CLRTAP) of the United Nations Economic Commission for Europe (UN-ECE). The German experience in forest monitoring
was a base for the implementation of the European monitoring system. In 2001 the interdisciplinary case study “concept and
feasibility study for the integrated evaluation of environmental monitoring data in forests”, funded by the German Federal
Ministry of Education and Research, concentrated on in-depths evaluations of the German data of forest monitoring. The objectives
of the study were: (a) a reliable assessment of the vitality and functioning of forest ecosystems, (b) the identification
and quantification of factors influencing forest vitality, and (c) the clarification of cause-effect-relationships leading
to leaf/needle loss. For these purposes additional data from external sources were acquired: climate and deposition, for selected
level I plots tree growth data, as well as data on groundwater quality. The results show that in particular time series analysis
(crown condition, tree growth, and tree ring analysis), in combination with climate and deposition are valuable and informative,
as well as integrated evaluation of soil, tree nutrition and crown condition data. Methods to combine information from the
extensive and the intensive monitoring, and to transfer process information to the large scale should be elaborated in future.
相似文献
Sabine AugustinEmail: |
20.
Adeljean L. F. C. Ho Nicole M. Orlando Bertran Junda Lin 《Journal of the World Aquaculture Society》2013,44(1):76-85
Anemonefishes dominate the marine ornamental aquaculture production and coloration plays an important role in market price of the product. This study examined the effect of dietary esterified astaxanthin concentration and duration on skin coloration in spinecheek anemonefish, Premnas biaculeatus. The chromatophore physiology parameters examined were color, density, and diameter of carotenoid granules. Juveniles of 30 days post hatch (d.p.h.) were fed diets consisting of 23, 214, or 2350 ppm esterified astaxanthin for 115 d and the fish were sampled at 45, 120, and 145 d.p.h. Hue was significantly reduced with increasing time and astaxanthin concentration. Saturation fluctuated over time while luminosity was only affected by time. Carotenoid granule density was similar across the treatments: approximately 0.3 granules/µm2. Significant difference in carotenoid granule size was detected, with larger diameters at the higher astaxanthin treatment. Carotenoid granules showed significantly lower hues, higher saturation, and lower luminosity values for the higher astaxanthin concentration diets. This is indicative of higher concentration of carotenoids in the granules. Diets explicitly imparted different coloration in P. biaculeatus and the manifested color differences in the fish are result of increased carotenoid granule size and increased carotenoid concentration within granules. Astaxanthin concentration of 214 ppm imparts adequate coloration for high market value. 相似文献