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991.
Vadim Girichev Magda-Viola Hanke Andreas Peil Henryk Flachowsky 《Genetic Resources and Crop Evolution》2017,64(1):189-203
Eighty-two genotypes of Rubus available in germplasm collections, nurseries and home gardens were collected and evaluated using a set of 16 simple sequence repeat (SSR) markers to estimate the level of genetic diversity and relatedness of the germplasm and for testing them on trueness-to-type. Each of the 16 SSRs was successful in amplifying alleles from most genotypes. Fifteen of the markers produced polymorphic bands, whereas marker RhM023 was monomorphic. The polymorphic information content among genotypes varied from 0.056 to 0.83 with an average of 0.348. A neighbor-joining analysis allocated the genotypes to four major clusters containing 11, 24, 39 and eight genotypes, respectively. Cluster I consists of floricane-fruiting cultivars originating from the Scottish and/or British breeding programs or cultivars which have those cultivars in their pedigree. Cluster II included cultivars that have ‘Autumn Bliss’ or ‘Tulameen’ in their pedigree. Cluster III consists of summer-bearing raspberry cultivars, some primocane-fruiting cultivars, and a few intermediate summer-fall-bearing types. Cluster IV consists of the blackberry ‘Navaho’ (R. fruticosus L.), the interspecific hybrid ‘Dorman Red’ and a few other raspberry varieties. A number of yellow fruited varieties was dispersed on three different clusters suggesting a convergent evolution of this trait. The pedigree of several genotypes could be confirmed using a Pedimap based approach, whereas other cultivars were found to be genetically identical. The results disclose the alarming narrow genetic base of Rubus resources in Germany. Broadening of this base is urgently needed. 相似文献
992.
Taru Lehtinen Georg Dersch Josef Söllinger Andreas Baumgarten Norman Schlatter Karl Aichberger 《Archives of Agronomy and Soil Science》2017,63(5):663-673
This study investigated the long-term effects of different composts (urban organic waste compost (OWC), green waste compost (GWC), cattle manure compost (MC) and sewage sludge compost (SSC)) compared to mineral fertilisation on a loamy silt Cambisol, after a 7-year start-up period. The compost application rate was 175 kg N ha?1, with 80 kg mineral N ha?1 and without. Soil characteristics (soil organic carbon (SOC), carbon-to-nitrogen (C/N) ratio and soil pH), nutrients (nitrogen (N), phosphorous (P) and potassium (K)) and crop yields were investigated between 1998 and 2012. SOC concentrations were increased by compost applications, being highest in the SSC treatments, as for soil pH. N contents were significantly higher with compost amendments compared to mineral fertilisation. The highest calcium-acetate-lactate (CAL)-extractable P concentrations were measured in the SSC treatments, and the highest CAL-extractable K concentrations in the MC treatments. Yields after compost amendment for winter barley and spring wheat were similar to 40 kg mineral N ha?1 alone, whereas maize had comparable yields to 80 kg mineral N ha?1 alone. We conclude that compost amendment improves soil quality, but that the overall carbon (C) and N cycling merits more detailed investigation. 相似文献
993.
Wendelin Weis Andreas Gruber Christian Huber Axel Göttlein 《European Journal of Forest Research》2009,128(5):437-445
Twenty years after the application of dolomitic limestone to a well growing, mature Norway spruce stand at Höglwald, Southern Germany an amount of magnesium equal to the input by liming has left the rooting zone. However, 80% of the applied calcium was retained by the ecosystem. A detailed biomass investigation was carried out in order to elaborate whether the stand shows any nutritional benefits and if the aboveground tree biomass represents a sink for calcium and magnesium after liming. Stem wood, bark, branches, twigs, and needles were analysed for the major nutrients. Needles showed higher calcium and magnesium concentrations and significantly lower potassium concentrations on the limed plot. Surprisingly, limed trees had significantly lower magnesium concentrations in the bark but higher concentrations in twigs and needles than unlimed trees. In addition, significantly lower concentrations for potassium, sulphur, and phosphorus were measured in the bark of limed trees, whereas the element concentrations in the wood were rather similar between the two treatments. The low potassium concentrations in bark and needles indicate an impeded potassium uptake after liming presumably due to a calcium potassium antagonism. Magnesium is probably used to compensate the relative lack of potassium. The small differences in the calculated nutrient storage of limed and unlimed trees, however, suggest that the aboveground biomass can be excluded as a relevant sink for the applied calcium and magnesium at the Höglwald site. 相似文献
994.
Karazafiris E Tananaki C Menkissoglu-Spiroudi U Thrasyvoulou A 《Pest management science》2008,64(2):165-171
Acaricide used in beehives for the control of varroa often leaves residues in bee products. The behaviour and distribution of the acaricide coumaphos in honey following the application of a new slow-release strip formulation (CheckMite+) was assessed. The bee colonies were allowed to build new combs without foundation, and two strips were hung in the brood chamber of each colony for a period of 42 days. The distribution of coumaphos residues in honey in relation to the position of the frame and the duration of treatment was examined by collecting samples from each comb at various time intervals up to 145 days after treatment. In the brood chamber, coumaphos was incorporated into honey from the first day of application, and residues accumulated mainly in combs placed next to strips. In the adjacent combs, residues remained at low concentrations with slight variations. In the honey chamber, residue concentrations on the day of strip removal ranged between 0.006 and 0.020 mg kg(-1), while 79 days after application the concentration of coumaphos residues was below 0.020 mg kg(-1). Residues above the EC fixed maximum residue limit (MRL) of 0.1 mg kg(-1) were measured only in brood chamber honey obtained from those combs placed next to strips. In these samples, 0.060-0.111 mg kg(-1) of coumaphos was detected up to 103 days after strip removal. Coumaphos residues in honey extracted from combs that were placed at the edge of the brood chamber were found below the MRL value, even during the 42 day period of CheckMite+ strip treatment. 相似文献
995.
Seizures or convulsions that occur during anaesthesia in veterinary patients are infrequently reported in the literature. Consequently, the incidence of such events is unknown. Several drugs commonly used in clinical veterinary anaesthesia have been shown to induce epileptiform activity in both human clinical patients and experimental candidates. The present case report describes convulsions in a four-year old male Bernese mountain dog during maintenance of anaesthesia with isoflurane after premedication with acepromazine and methadone followed by co-induction with propofol and ketamine. The dog had no history of previous convulsions. The use of several sedative and anaesthetic drugs makes it difficult to find one single causative pharmaceutical. 相似文献
996.
Harkins JD Dirikolu L Lehner AF Hughes C Schroedter D Mayer B Bratton C Fisher MV Tobin T 《Veterinary therapeutics : research in applied veterinary medicine》2003,4(2):197-209
Guanabenz (2,6-dichlorobenzylidene-amino-guanidine) is a centrally acting antihypertensive drug whose mechanism of action is via alpha2 adrenoceptors or, more likely, imidazoline receptors. Guanabenz is marketed as an antihypertensive agent in human medicine (Wytensin tablets, Wyeth Pharmaceuticals). Guanabenz has reportedly been administered to racing horses and is classified by the Association of Racing Commissioners International as a class 3 foreign substance. As such, its identification in a postrace sample may result in significant sanctions against the trainer of the horse. The present study examined liquid chromatographic/tandem quadrupole mass spectrometric (LC-MS/MS) detection of guanabenz in serum samples from horses treated with guanabenz by rapid i.v. injection at 0.04 and 0.2 mg/kg. Using a method adapted from previous work with clenbuterol, the parent compound was detected in serum with an apparent limit of detection of approximately 0.03 ng/ml and the limit of quantitation was 0.2 ng/ml. Serum concentrations of guanabenz peaked at approximately 100 ng/ml after the 0.2 mg/kg dose, and the parent compound was detected for up to 8 hours after the 0.04 mg/kg dose. Urine samples tested after administration of guanabenz at these dosages yielded evidence of at least one glucuronide metabolite, with the glucuronide ring apparently linked to a ring hydroxyl group or a guanidinium hydroxylamine. The LC-MS/MS results presented here form the basis of a confirmatory test for guanabenz in racing horses. 相似文献
997.
998.
Assuming a synergistic or additive effect of Chlamydiaceae in coexistence with other enteropathogenic agents, the viral/bacterial interaction between a cell culture adapted porcine epidemic diarrhea virus (ca-PEDV) and different Chlamydiaceae strains was studied in vitro. Vero cells were dually infected with ca-PEDV and one of the three chlamydial strains Chlamydia trachomatis S45, Chlamydophila abortus S26/3 or Chlamydophila pecorum 1710S. Three experimental protocols were designed varying the inoculation sequence. Cell layers were first inoculated with Chlamydiaceae and 20 h later with ca-PEDV in protocol one. In protocol two, both agents were administered concurrently, whereas in protocol three, ca-PEDV was applied 20 h in advance of the Chlamydiaceae. Immunofluorescence techniques, immunohistochemical (IH) staining and electron microscopy were subsequently employed to investigate the cell layers. Using indirect immunofluorescence (IF) labeling, all mixed infections revealed dually infected cells, however, only incidentally and in low numbers. Characteristically, ca-PEDV syncytia with one or more chlamydial inclusions were detected but dually infected single cells were absent. Some syncytial cells contained enlarged C. abortus or C. pecorum inclusions with abnormally large developmental forms. In comparison with simultaneously conducted monoinfections, larger chlamydial inclusions were observed in dually infected cell layers. Experiments with C. trachomatis showed significantly increased numbers of chlamydial inclusions in dually infected cell layers compared to monoinfected ones. These findings indicate an influence of ca-PEDV on the chlamydial developmental cycle and in the case of C. trachomatis, a positive effect on chlamydial colonization in mixed infections. 相似文献
999.
Mihalev K Schieber A Mollov P Carle R 《Journal of agricultural and food chemistry》2004,52(24):7306-7310
The effects of enzymatic mash treatments on yield, turbidity, color, and polyphenolic content of cloudy apple juice were studied. Using HPLC-ESI-MS, cryptochlorogenic acid was identified in cv. Brettacher cloudy apple juice for the first time. Commercial pectolytic enzyme preparations with different levels of secondary protease activity were tested under both oxidative and nonoxidative conditions. Without the addition of ascorbic acid, oxidation substantially decreased chlorogenic acid, epicatechin, and procyanidin B2 contents due to enzymatic browning. The content of chlorogenic acid as the major polyphenolic compound was also influenced by the composition of pectolytic enzyme preparations because the presence of secondary protease activity resulted in a rise of chlorogenic acid. The latter effect was probably due to the inhibited protein-polyphenol interactions, which prevented binding of polyphenolic compounds to the matrix, thus increasing their antioxidative potential. The results obtained clearly demonstrate the advantage of the nonoxidative mash maceration for the production of cloud-stable apple juice with a high polyphenolic content, particularly in a premature processing campaign. 相似文献
1000.
Stein VM Czub M Hansen R Leibold W Moore PF Zurbriggen A Tipold A 《Veterinary immunology and immunopathology》2004,99(1-2):73-85
Microglia are the principal immune effector elements of the brain sharing immunophenotypic and functional characteristics of macrophages as well as of antigen presenting cells (APCs). The purpose of this study was to isolate canine microglial cells and make them available for ex vivo characterizations of their functions and immunophenotype. After isolation, carried out by density gradient centrifugation, microglial cells accumulated on distinct interfaces of 1.077 and 1.066 g/ml of a Percoll gradient. Identification of microglial cells in other species is realized by their specific immunophenotype of CD11b/c+ and CD45low. Our results indicate, that expression of CD45 is very low or even absent in canine microglial cells. In addition, they expressed CD18 and CD11b/c+, as determined by flow cytometry and immunohistochemistry. Fourteen additional monoclonal antibodies (mAbs) were used to characterize and compare canine microglial cells with monocytes. Microglia and monocytes can be clearly distinguished by their differential expression intensity of surface antigens (CD45, CD44, CD14). Functional characterization was assessed by a reactive oxygen species (ROS)-generation test and phagocytosis assay using flow cytometry. In conclusion, ex vivo examination of microglia is possible in dogs and most probably reflects the conditions in vivo. The measurement of tissue culture artifacts can be largely avoided using this method. 相似文献