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921.
Atypical myopathy is highly fatal, but about a quarter of affected horses survive. This highlights the need for provision of supportive treatment for these cases. This review is a practical guideline for equine practitioners and includes suggestions for close monitoring of involved organ systems and discusses options of supportive treatment based on current knowledge of the condition.  相似文献   
922.
OBJECTIVES: To assess participants' acquaintance with and willingness to try healthful food alternatives, and to test the psychometric properties of an adapted Dutch version of the Food Neophobia Scale (FNS) in order to study the role of food neophobia in this context. DESIGN: A cross-sectional study incorporating two web-based questionnaires, including a retest of the FNS one week later. Measures included acquaintance with and willingness to try 15 healthful food alternatives, level of food neophobia, level of education, gender and age. Multiple linear regression analyses were used to study associations between demographics and level of food neophobia as well as associations between level of food neophobia and acquaintance with and willingness to try the healthful alternatives. SETTING: The study was conducted in The Netherlands using a representative Internet panel. PARTICIPANTS: A total of 326 participants aged 18-50 years participated. RESULTS: Internal consistency and test-retest reliability of the FNS version used were sufficient. On average participants were acquainted with 7.9 of the products and modestly willing to try the products. Lowly educated participants had significantly higher FNS scores than highly educated participants (beta = -0.23, P < 0.01). FNS score was significantly associated with acquaintance with (beta = -0.21, P < 0.001) and willingness to try the healthful alternatives (beta = -0.26, P < 0.001).CONCLUSION: Further research into the role of food neophobia is warranted when wanting to stimulate the integration of healthful alternative products in the daily diet, especially among persons with low education.  相似文献   
923.
Alkylpyrazines are a very important class of Maillard flavor compounds, but their mechanism of formation is complex and consists of different pathways. The model reaction of 20 different amino acids with 1,3-dihydroxyacetone, as a precursor of 2-oxopropanal, was studied by means of SPME-GC-MS to investigate the involvement of the amino acid side chain in the substitution pattern of the resulting pyrazines. 2,5-Dimethylpyrazine was quantitatively the most important pyrazine formed from all of the amino acids. The amino acid side chain is not involved in its formation. The substituents of other less abundant pyrazines resulted mainly from the incorporation of the Strecker aldehyde or aldol condensation products in the intermediate dihydropyrazine. The importance of different reaction mechanisms was evaluated, taking into account the pattern of pyrazines identified. In the solvent extracts of aqueous model reactions of 2-oxopropanal with amino acids, the main reaction product was not a pyrazine but a novel pyrrole. This pyrrole was identified as 2,5-diacetyl-3-methyl-1 H-pyrrole by means of spectral analysis, secured by chemical synthesis. A reaction mechanism for its formation was proposed and evaluated. The influence of various reaction conditions on the formation of 2,5-diacetyl-3-methyl-1 H-pyrrole and 2,5-dimethylpyrazine in the model reaction of alanine with 2-oxopropanal was studied. These results underscore the importance of the ratio of the different reagents and the presence of water in the resulting flavor formation in the Maillard reaction.  相似文献   
924.
Over a 2-year study, we investigated the effect of environmental change on the diversity and abundance of soil arthropod communities (Acari and Collembola) in the Maritime Antarctic and the Falkland Islands. Open Top Chambers (OTCs), as used extensively in the framework of the northern boreal International Tundra Experiment (ITEX), were used to increase the temperature in contrasting communities on three islands along a latitudinal temperature gradient, ranging from the Falkland Islands (51°S, mean annual temperature 7.5 °C) to Signy Island (60°S, ?2.3 °C) and Anchorage Island (67°S, ?3.8 °C). At each island an open and a closed plant community were studied: lichen vs. moss at the Antarctic sites, and grass vs. dwarf shrub at the Falkland Islands. The OTCs raised the soil surface temperature during most months of the year. During the summer the level of warming achieved was 1.7 °C at the Falkland Islands, 0.7 °C at Signy Island, and 1.1 °C at Anchorage Island.The native arthropod community diversity decreased with increasing latitude. In contrast with this pattern, Collembola abundance in the closed vegetation (dwarf shrub or moss) communities increased by at least an order of magnitude from the Falkland Islands (9.0 ± 2 × 103 ind. m?2) to Signy (3.3 ± 8.0 × 104 ind. m?2) and Anchorage Island (3.1 ± 0.82 × 105 ind. m?2). The abundance of Acari did not show a latitudinal trend.Abundance and diversity of Acari and Collembola were unaffected by the warming treatment on the Falkland Islands and Anchorage Island. However, after two seasons of experimental warming, the total abundance of Collembola decreased (p < 0.05) in the lichen community on Signy Island as a result of the population decline of the isotomid Cryptopygus antarcticus. In the same lichen community there was also a decline (p < 0.05) of the mesostigmatid predatory mite Gamasellus racovitzai, and a significant increase in the total number of Prostigmata.Overall, our data suggest that the consequences of an experimental temperature increase of 1–2 °C, comparable to the magnitude currently seen through recent climate change in the Antarctic Peninsula region, on soil arthropod communities in this region may not be similar for each location but is most likely to be small and initially slow to develop.  相似文献   
925.
One of the major limitations to enhance sustainability of crop production systems is the inability to control root-feeding nematodes without using chemical biocides. In soils under wild vegetation, however, root-feeding nematodes affect plant performance and plant community composition varying from substantially to insignificantly. Previous studies in natural ecosystems have already shown that mutualistic symbionts, such as arbuscular mycorrhizal fungi and endophytes, may influence plant exposure to root-feeding nematodes. In order to learn more from natural systems, we examined nematode control in the root zone of a wild coastal foredune grass by microorganisms, other nematodes and microarthropods. We cultured all eight root-feeding nematode species that occur in the root zone of marram grass (Ammophila arenaria) in coastal foredunes of the Netherlands. Then, in an indoor growth experiment we exposed each nematode species to the potential natural antagonists collected from the same dune soil. Most of the eight dominant root-feeding nematode species could be controlled to some extent by more than one group of soil organisms added. The effectiveness of control varied among nematode species, which seemed to be controlled in a species-specific way. We conclude that in a natural soil the effectiveness of control by microorganisms, other nematodes or microarthropods varies among root-feeding nematode species. Most are controlled, at least to some extent, by soil microbes. However, some root-feeding nematode species are controlled only by microarthropods. Our results strongly suggest that sustainable agriculture will benefit from using a range of biological control mechanisms when controlling root-feeding nematodes, rather than relying on single control agents. Our suggestion also implies that conserving soil biodiversity is crucial in order to enhance the reliability of biological crop protection against soil-borne pests and diseases.  相似文献   
926.
When a field or a small watershed is repeatedly surveyed for soil water content, locations can often be identified where soil water contents are either consistently larger or consistently less than the study area average. This phenomenon has been called temporal stability, time stability, temporal persistence, or rank stability in spatial patterns of soil water contents. Temporal stability is of considerable interest in terms of facilitating upscaling of observed soil water contents to obtain average values across the observation area, improving soil water monitoring strategies, and correcting the monitoring results for missing data. The objective of this work was to contribute to the existing knowledge base on temporal stability in soil water patterns using frequent multi-depth measurements with Multisensor Capacitance Probes (MCPs) installed in a coarse-texture soil under multi-year corn production. Water contents at 10, 30, 50, and 80 cm depths were measured every 10 min for 20 months of continuous observation from May 2001 to December 2002. The MCPs revealed temporal stability in soil water content patterns. Temporal stability was found to increase with depth. The statistical hypothesis could not be rejected (P < 0.0001) that data collected each 10 min, each 2 h, each day, and each week had the same temporal stability. The locations that were best for estimating the average water contents were different for different depths. The best three locations for the whole observation period were the same as the best locations for a month of observations in about 60% of the cases. Temporal stability for a specific location and depth could serve as a good predictor of the utility of this location for estimating the area-average soil water content for that depth. Temporal stability could be efficiently used to correct area-average water contents for missing data. Soil water contents can be upscaled and efficiently monitored using the temporal stability of soil water content patterns.  相似文献   
927.
Cultivar development of cowpea with increased grain yield depends on evaluation and selection of genetically unique and complementary breeding lines. The objective of this study was to evaluate cowpea collections using agronomic traits to select promising parents to develop breeding population. Twenty-two cowpea genotypes were field evaluated using a randomised complete block design with three replications in two locations in South Africa. Analysis of variance revealed significant genotypic (G) and locations (L) differences for all agronomic traits evaluated. Significant differences were also observed for most of the traits due to G X L, G X Year (Y), L X Y and G X L X Y interactions effects. The genotypes tested at two locations showed considerable genetic variation for the following agronomic traits that varied for number of leaves (NL) (20.08–179.78), leaf length (LL) (12.36–67.72 cm), leaf width (LW) (4.78–22.02 cm), number of branches (NB) (6.81–13.85), number of pods per plant (NPPP) (14.33–54.04), number of seeds per pod (NSPP) (11.7286.28), pod diameter (PD) (5.75–22.73 mm), plant height (PH) (6.57–233.71 cm), pod length (PL) (3.94–100.92 mm), hundred seed weight (HSWt) (8.11–49.52 g) and grain yield (GY) (0.10-1.48 t ha?1). Grain yield was significant and positively correlated with all of the traits except leaf length. The principal component analysis (PCA) identified four principal components (PCs) contributing to 73.62% of the total explained variation amongst the tested genotypes. The selected cowpea genotypes for most of agronomic characteristics are useful and candidate genetic resources for the development of breeding population in cowpea breeding and enhanced production and productivity for food and nutrition in the country.  相似文献   
928.
The main objective of the present study was to investigate if different kinds of pig farms, like farrowing farms and rearing farms, play a role in the transmission of methicillin-resistant Staphylococcus aureus (MRSA) to Dutch finishing farms. Twelve farrowing farms, 11 finishing farms, 6 farrow-to finish farms, 1 rearing farm and 1 centre for artificial insemination were included. Screening of 310 pigs from these 31 farms showed 35 pigs (11%) to carry MRSA in their nares. On 7 of the 31 (23%) investigated farms colonized pigs were found, including 3 finishing farms, 3 farrowing farms and 1 farrow-to-finish farm. The use of standard antimicrobial medication of the pigs seemed to be a risk factor for MRSA carriage. Screening of the pigs on six farms supplying pigs for the MRSA positive farms revealed that the pigs on all but one farm were MRSA positive. Genotyping revealed that all MRSA strains were non-typeable by PFGE using the SmaI restriction enzyme and had multilocus sequence type (MLST) ST398. Different spa-types were found including t011, t108, t567, t899 and t1939, but the spa-types on epidemiologically related farms were identical indicating that MRSA are transmitted between farms through the purchase of colonized pigs. Two SCCmec types were found among the MRSA: type IV and type V. SCCmec type V was predominant. On two farms MRSA isolates with ST398, the same spa-type but with different SCCmec types (IV and V) were found, suggesting that different SCCmec elements have been inserted into MSSA with the same genotype. All MRSA strains were resistant to tetracycline, but additional resistances to erythromycin, lincomycin, kanamycin and gentamicin were also found. All MRSA isolates were negative for the exfoliative toxin genes (eta and etb), PVL toxin genes (lukF and lukS), toxic shock syndrome gene (tst-1), and the leukotoxin genes (lukE, lukD, lukM, lukF').  相似文献   
929.
Clostridium perfringens which is a causative agent of several diseases in animals and humans is capable of producing a variety of toxins. Isolates are typed into five types on the basis of the presence of one or more of the four major toxins genes, i.e. cpa, cpb, etx, and iap. A decade ago another toxin termed beta2 (beta2) and its gene (cpb2) were identified. Two alleles of cpb2 are known and a possible link between differences in gene expression and allelic variation has been reported. A correlation between the level of expression and the origin of the isolates has also been suggested. The demonstration and typing of the cpb2 gene in the genome of isolates can be seen as a vital part of research on the role of the beta2 toxin in the pathogenesis of disease. This study describes a PCR with a single primer set which in contrast to published primer sets recognizes both alleles. Subsequent restriction enzyme analysis of the PCR product enables typing of the alleles. Applying this protocol on a total of 102 isolates, a sub-variant was found which occurred only in C. perfringens isolates from pigs and appeared to be the predominant variant found in C. perfringens isolates from this species.  相似文献   
930.
Polyneuritis equi (PNE) is a rare neurological disease in the horse. Because of the suspicion in PNE of a T-lymphocyte mediated immune response against the myelin, the objective of this study was to determine the composition of the inflammatory infiltrate in the involved nerves of 3 horses with PNE, studied retrospectively. T-lymphocytes were demonstrated in the lesions, which suggests a T-lymphocyte mediated immune response against myelin. In addition, the presence of B-lymphocytes indicated a local production of antibodies. More research, involving a prospective study, is needed to determine whether the T-lymphocytes are cytotoxic or T-helper lymphocytes.  相似文献   
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