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81.
In the present study 20 staphylococci isolated from lymph node abscesses of 19 goats of two herds in Western Poland could be identified as Staphylococcus aureus subsp. anaerobius. All 20 strains grew under microaerobic conditions, were negative in the catalase test, showed the typical phenotypic properties of 5. aureus and could genotypically be identified by a positive sa442, 235 rDNA, nuc, coa and spa PCR reaction. The variable regions of the coa and spa gene of the 20 strains appeared with uniform amplicon sizes, respectively. All 20 strains were negative for 12 additionally investigated enterotoxin encoding genes, tst and ssl7 and positive for the gene cap8. Identical properties could be observed for S. aureus subsp. anaerobius DSM 20714. Amplification and sequencing of kat gene of a single Staphylococcus aureus subsp. anaerobius strain of the present study and S. aureus subsp. anaerobius DSM 20714 revealed a complete identity of the kat sequences of both strains and a katB sequence obtained from GenBank (AJ000471). The bacteria were additionally investigated for relatedness by macrorestriction analysis of chromosomal DNA with subsequent pulsed-field gel electrophoresis (PFGE), yielding, corresponding to the above mentioned PCR results, identical PFGE patterns for all 20 Staphylococcus aureus subsp. anaerobius strains isolated in Western Poland and the S. aureus subsp. anaerobius reference strain DSM 20714.This indicates the clonal identity of the strains isolated in Western Poland and the S. aureus subsp. anaerobius reference strain. The route of infection of the two herds in Western Poland with a bacterial clone originally isolated in Spain remains unclear.  相似文献   
82.
Molecularly imprinted solid phase extraction (MISPE) has been employed to isolate and concentrate bioactive polyphenols from peanut press waste. To this end, a molecularly imprinted polymer (MIP) templated with the phytoalexin (E)-resveratrol has been prepared via self-assembly with the functional monomer 4-vinylpyridine (4VP) in a 1:3 molar ratio. Subsequent molecular interrogation of the MIP binding sites demonstrated preferential structural selectivity for (E)-resveratrol with respect to other structurally related naturally occurring compounds. This selectivity was subsequently exploited to achieve substantial sample cleanup of peanut press waste under aqueous conditions with significant enrichment of (E)-resveratrol (>60 fold) requiring minimal sample preparation.  相似文献   
83.
The present study determined the influence of initial moisture conditions on the production and consumption of nitrous oxide (N2O) during denitrification and on the isotopic fingerprint of soil-emitted N2O. Sieved arable soil was pre-incubated at two different moisture contents: pre-wet at 75% and pre-dry at 20% water-filled pore space. After wetting to 90% water-filled pore space the soils were amended with glucose (400 kg C ha−1) and KNO3 (80 kg N ha−1) and incubated for 10 days under a He/O2-atmosphere. Antecedent moisture conditions affected denitrification. N2 + N2O fluxes and the N2O-to-N2 ratio were higher in soils which were pre-incubated under dry conditions, probably because mobilization of organic C during the pre-treatment enhanced denitrification. Gaseous N fluxes showed similar time patterns of production and reduction of N2O in both treatments, where N2O fluxes were initially increasing and maximised 3-4 days after fertilizer application, and N2 fluxes were delayed by 1-2 days. Time courses of δ15Nbulk-N2O and δ18O-N2O exhibited in both treatments increasing trends until maximum N2 fluxes occurred, reflecting isotope fractionation during intense NO3 reduction. Later this trend slowed down in the pre-dry treatment, while δ18O-N2O was constant and δ15Nbulk-N2O decreased in the pre-wet treatment. We explain these time patterns by non-homogenous distribution of NO3 and denitrification activity, resulting from application of NO3 and glucose to the surface of the soil. We assume that several process zones were thus created, which affected differently the isotopic signature of N2O and the N2O and N2 fluxes during the different stages of the process. We modelled the δ15Nbulk-N2O using process rates and associated fractionation factors for the pre-treated soils, which confirmed our hypothesis. The site preference (SP) initially decreased while N2O reduction was absent, which we could not explain by the N-flux pattern. During the subsequent increase in N2 flux, SP and δ18O-N2O increased concurrently, confirming that this isotope pattern is indicative for N2O reduction to N2. The possible effect of the antecedent moisture conditions of the soil on N2O emissions was shown to be important.  相似文献   
84.
Marasmin, which is especially known from the two South African species Tulbaghia alliacea and Tulbaghia violacea , but was also described for the garlic mushroom Marasmius alliaceus , is the precursor of the thiosulfinate marasmicin. Marasmicin has attracted considerable attention because of its antifungal and tuberculostatic activities. However, many Allium species of the subgenus Melanocrommyum, especially Allium suworowii , are also very rich in marasmin. A. suworowii revealed concentrations of marasmin up to 1.6%, related to the fresh weight of bulbs, and up to 3.0%, related to air-dried fruiting bodies, of the corresponding γ-glutamylmarsmin was found in M. alliaceus. Both species show much higher amounts of marasmin as Tulbaghia and could be considered as natural sources for the isolation of this compound. Further promising Allium species with considerable amounts of marasmin besides other cysteine sulfoxides are Allium stipitatum and Allium altissimum . (R(S),R(C))-Marasmin is typical for the investigated species of the subgenus Melanocrommyum, whereas γ-glutamyl-(S(S),R(C))-marasmin is the only cysteine sulfoxide for the genus Marasmius known until now. Both cysteine sulfoxides were isolated and described as o-phthaldialdehyde (OPA) derivatives. Furthermore, the cysteine sulfoxides methiin, propiin, S-(2-pyrrolyl)-cysteine sulfoxide, eventually S-(2-pyridyl)-cysteine sulfoxide and S-(2-pyridyl)-L-cysteine N-oxide were found.  相似文献   
85.
86.
Allergic contact dermatitis affects about 5% of men and 11% of women in industrialized countries and is one of the leading causes for occupational diseases. In an animal model for cutaneous contact hypersensitivity, we show that mice lacking both known cannabinoid receptors display exacerbated allergic inflammation. In contrast, fatty acid amide hydrolase-deficient mice, which have increased levels of the endocannabinoid anandamide, displayed reduced allergic responses in the skin. Cannabinoid receptor antagonists exacerbated allergic inflammation, whereas receptor agonists attenuated inflammation. These results demonstrate a protective role of the endocannabinoid system in contact allergy in the skin and suggest a target for therapeutic intervention.  相似文献   
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89.
People suffering from food allergies are dependent on accurate food labeling, as an avoidance diet is the only effective countermeasure. Even a small amount of allergenic protein can trigger severe reactions in highly sensitized patients. Therefore, sensitive and reliable tests are needed to detect potential cross-contamination. In this paper two fast sandwich immunoassays are described for the determination of peanut (Arachis hypogaea) and hazelnut (Corylus avellana) traces in complex food matrices. Mouse monoclonal antibodies were used as capture antibodies, and labeled rabbit polyclonal antibodies were used as detection antibodies in both assays. The assay time was 30 min in total, and cross-reactivities against a variety of fruits and seeds were found to be in the low 10(-4)% (ppm) level or in some cases not detectable. The recoveries in all tested food matrices ranged from 86 to 127%, and the limits of detection were in the range of 0.2-1.2 mg/kg (ppm) in food for both peanut and hazelnut, respectively.  相似文献   
90.
The adnexa frequently requires the general practitioner to intervene surgically to manage underlying disease or as an ancillary aid in the management of corneal disease. Both acquired and hereditary disorders are encountered. This article reviews general anatomy and physiology of the eyelids and discusses indications for the more commonly performed surgical procedures and their execution. Procedures include tarsorrhaphy, management of eyelid lacerations, eyelid tumor resection, correction of upper and/or lower lid entropion, ectropion, a medial and lateral canthoplasty, colobomatous syndrome in the cat, management of distichiasis, trichiasis and ectopic ciliae, and reduction of a prolapse of the gland of the third eyelid. Finally a surgical pack inventory useful for adnexal surgery is described.  相似文献   
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