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71.
The development and in-house testing of a method for the quantification of milk fat in chocolate fats is described. A database consisting of the triacylglycerol profiles of 310 genuine milk fat samples from 21 European countries and 947 mixtures thereof with chocolate fats was created under a strict quality control scheme using 26 triacylglycerol reference standards for calibration purposes. Out of the individual triacylglycerol fractions obtained, 1-palmitoyl-2-stearoyl-3-butyroyl-glycerol (PSB) was selected as suitable marker compound for the determination of the proportion of milk fat in chocolate fats. By using PSB values from the standardized database, a calibration function using simple linear regression analysis was calculated to be used for future estimations of the milk fat content. A comparison with the widely used butyric acid method, which is currently used to determine the milk fat content in nonmilk fat mixtures, showed that both methods were equivalent in terms of accuracy. The advantage of the presented approach is that for further applications, i.e., determination of foreign fats in chocolate fats, just a single analysis is necessary, whereas for the same purpose, the C4 method requires two different analytical methods.  相似文献   
72.
Malassezia spp. yeasts are commensal organisms of mammal and avian skin, but little is known about their presence on the skin of healthy cats. The purposes of this study were to evaluate the prevalence of Malassezia spp. yeasts in feline nail folds and to identify the different species. Forty-six cats of different breeds were evaluated by cytological examination, and Malassezia spp. yeasts were seen in 61% of them. Yeasts were found in 100% of Devon Rex cats [mean 8.63/oil immersion field (high-power field - HPF)]. Conversely, only 42% of cats of other breeds (domestic short-haired and Persian) were positive (mean 0.59/HPF). Twenty-one cats of different breeds were subsequently evaluated by fungal culture. Malassezia pachydermatis was isolated from 52%, M. furfur from 38%, and M. sympodialis from 9.5% of the cats. More than one species was observed in eight of 21 cats, six of which were Devon Rex. Malassezia spp. yeasts are common inhabitants of feline nail folds, especially in Devon Rex cats, and the presence of a high number of yeasts on cytology correlates with the clinical observation of brown, greasy material in the nail folds. M. pachydermatis and two lipid-dependent species were isolated from both Devon Rex cats and cats of other breeds.  相似文献   
73.
The antibiotic block technique is used to distinguish between fungal and bacterial induced activity. In the present study, the antibiotic inhibition of peptone-induced NO3 production was tested across a soil moisture gradient. Soil was incubated at 60, 80, 90 and 100% water-filled pore space (WFPS) and as a water slurry. Peptone was used as the substrate and cycloheximide and C2H2 (0.1% v/v) were added to inhibit fungal and autotrophic nitrification, respectively, the latter being considered mainly of bacterial origin. At all moisture contents is more than 80% of NO3 production was due to autotrophic nitrification. At increasing water contents the percentage of NO3 production inhibited by C2H2 increased, whereas the percentage inhibited by cycloheximide decreased from 26.4% at 60% WFPS to 4.6% in the water slurry, suggesting a different sensitivity of bacterial and fungal nitrification to soil moisture. Although no direct evidence of an alteration in the fungal population was produced in this experiment, data proved that water content influences the result of the test and hence care should be taken when comparing data using different test conditions.  相似文献   
74.
75.
We hypothesized that fruit ingestion provides measurable amounts of salicylic acid (SA) and produces different metabolic and inflammatory responses compared to mere fruit sugars. In a randomized-crossover study, 26 healthy subjects received a peach shake meal (PSM) (SA: 0,06 ± 0,001 mg/100 g) and a mixed sugar meal (MSM), consisting in an aqueous solution with the same sugars found in the peach shake. In order to control for the SA contribution from meals in the previous day, 16 subjects (Group 1) abstained from fruits and vegetables consumption the evening before trials, and 10 subjects (Group 2) maintained their usual diet. Circulating SA, glucose, insulin, free fatty acids, and interleukin-6 were determined. Basal SA was lower in Group 1 than in Group 2 (0.09 ± 0.02 vs. 0.30 ± 0.03 μmol/l, p < 0.001), peaked at 90 min in both groups (0.18 ± 0.01 vs. 0.38 ± 0.02 μmol/l, p < 0.01) and remained above baseline (p < 0.05) up to 3 h. Glycemia increased less after PSM at 15 min (p < 0.01) with a lower average glucose excursion (p < 0.05). Insulin peaked at 45 min with both meals but decreased less rapidly with PSM. Free fatty acids decreased more (p < 0.01), and interleukin-6 increased less (p < 0.05) with PSM. Dietary fruit intake increases the concentration of SA in vivo, and provides non-nutrients capable to modulate the inflammatory and metabolic responses to carbohydrates.  相似文献   
76.
Effects of physiological saline (PS)-dissolved or Freund′s incomplete adjuvant (FIA)-emulsified sGnRHa on the induction and advancement of ovulation in brook char were assessed. Two-year-old females were randomly divided into 5 groups. Groups A and B received intraperitoneal injection of FIA-emulsified sGnRHa (sGnRHa-FIA) at dosages of 50 and 25 μg kg?1 body weight (BW), respectively. Females in group C were treated with a double injection (DI) of PS-dissolved sGnRHa (sGnRHa-PS) at 25 μg kg?1 BW spaced 3 days apart. Fish in group D received a 25 μg kg?1 BW single injection (SI) of sGnRHa-PS. Group E was established as a control group. After stripping, ovarian plasma pH level was measured, and an egg sample was taken from each female to record egg weight and diameter and survival to the eyed stage. Females in the GnRHa-treated groups ovulated significantly earlier than did females in the control group (P < 0.01). No significant differences were found among GnRHa-treated groups in ovulation dynamics and mean time to ovulation. Ovarian fluid pH was significantly higher in groups A, B, and C compared to control group E (P < 0.05). Significantly lower egg weight was found only in group B (P < 0.01), although all advanced groups tended to have lower egg weight than the control group. Egg diameters paralleled egg weight. Survival to the eyed stage was significantly higher in GnRHa-advanced groups compared to the control. A negative relationship was found between egg weight end eyed eggs percent (R 2 = 0.26). No pre-spawning or post-spawning mortality was observed during a 6-month period. Neither sGnRHa-PS nor sGnRHa-FIA are associated with negative influences on the health of females. The sGnRHa-FIA injections proved to exhibit the same efficacy as the DI protocol with sGnRHa-PS. Although no statistical differences were found in ovulation dynamics, we do not recommend the use of SI with sGnRHa-PS in brook char.  相似文献   
77.
Enzyme treatment technologies in textile processing have become commonly-applied techniques for the modification of fabric-handle appearance, and other surface and mechanical characteristics of fabrics. Most studies have focused on understanding the impact of enzyme treatments on the fabric preparation, dyeing, and finishing processes of woven fabrics, whilst only limited research has been reported regarding any enzymatic effects on the surface and handproperties of knitted fabrics. The aim of this study was to analyze the effects of two different enzymes Trichoderma reesei whole cellulase, and enriched (EGIII) endoglucanase cellulase, at three different enzyme dosages on 100 % cotton interlock knitted fabric. This was in order to evaluate certain surface properties such as pilling, friction. and geometrical roughness. Furthermore, the compression and tactile properties of knitted fabric were also analyzed. The results show that treatment conditions with enzyme Trichoderma reesei whole cellulase had the more pronounced effect on the surface properties compared to the enriched EGIII enzymes. In general, it can be concluded that both types of enzymes improved the surface properties and hand when compared with the silicone softener-treated reference sample of interlock knitted fabric, as is statistically confirmed by one-way analysis of variance.  相似文献   
78.
Currently, the larviculture of many marine fish species with small-sized larvae depends for a short time after hatching, on the supply of high-quality live zooplankton to ensure high survival and growth rates. During the last few decades, the research community has made great efforts to develop artificial diets, which can completely substitute live prey. However, studies aimed at determining optimal levels of minerals in marine larvae compound feeds and the potential of novel delivery vectors for mineral acquisition has only very recently begun. Recently, the agro-food industry has developed several nano-delivery systems, which could be used for animal feed, too. Delivery through nano-encapsulation of minerals and feed additives would protect the bioactive molecules during feed manufacturing and fish feeding and allow an efficient acquisition of active substances into biological system. The idea is that dietary minerals in the form of nanoparticles may enter cells more easily than their larger counterparts enter and thus speed up their assimilation in fish. Accordingly, we evaluated the efficacy of early weaning diets fortified with organic, inorganic, or nanoparticle forms of trace minerals (Se, Zn, and Mn) in gilthead seabream (Sparus aurata) larvae. We tested four experimental diets: a trace mineral-deficient control diet, and three diets supplemented with different forms of trace minerals. At the end of the feeding trial, larvae growth performance and ossification, and the level of expression of six target genes (SLC11A2β, dmt1, BMP2, OC, SOD, GPX), were evaluated. Our data demonstrated that weaning diets supplemented with Mn, Se, and Zn in amino acid-chelated (organic) or nanoparticle form were more effective than diets supplemented with inorganic form of minerals to promote bone mineralization, and prevent skeletal anomalies in seabream larvae. Furthermore, nanometals markedly improved larval stress resistance in comparison to inorganic minerals and upregulated mRNA copy number of OC gene. The expression of this gene was strongly correlated with mineralization degree, thus confirming its potency as a good marker of bone mineralization in gilthead seabream larvae.  相似文献   
79.
80.
The cytochrome b (cyt b) gene structure was characterized for different agronomically important plant pathogens, such as Puccinia recondita f sp tritici (Erikss) CO Johnston, P graminis f sp tritici Erikss and Hennings, P striiformis f sp tritici Erikss, P coronata f sp avenae P Syd & Syd, P hordei GH Otth, P recondita f sp secalis Roberge, P sorghi Schwein, P horiana Henn, Uromyces appendiculatus (Pers) Unger, Phakopsora pachyrhizi Syd & P Syd, Hemileia vastatrix Berk & Broome, Alternaria solani Sorauer, A alternata (Fr) Keissl and Plasmopara viticola (Berk & Curt) Berlese & de Toni. The sequenced fragment included the two hot spot regions in which mutations conferring resistance to QoI fungicides may occur. The cyt b gene structure of these pathogens was compared with that of other species from public databases, including the strobilurin-producing fungus Mycena galopoda (Pers) P Kumm, Saccharomyces cerevisiae Meyer ex Hansen, Venturia inaequalis (Cooke) Winter and Mycosphaerella fijiensis Morelet. In all rust species, as well as in A solani, resistance to QoI fungicides caused by the mutation G143A has never been reported. A type I intron was observed directly after the codon for glycine at position 143 in these species. This intron was absent in pathogens such as A alternata, Blumeria graminis (DC) Speer, Pyricularia grisea Sacc, Mycosphaerella graminicola (Fuckel) J Schr?t, M fijiensis, V inaequalis and P viticola, in which resistance to QoI fungicides has occurred and the glycine is replaced by alanine at position 143 in the resistant genotype. The present authors predict that a nucleotide substitution in codon 143 would prevent splicing of the intron, leading to a deficient cytochrome b, which is lethal. As a consequence, the evolution of resistance to QoI fungicides based on G143A is not likely to evolve in pathogens carrying an intron directly after this codon.  相似文献   
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