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排序方式: 共有327条查询结果,搜索用时 31 毫秒
191.
192.
Anna Dziekoska Magdalena Koziorowska-Gilun Wadysaw Kordan Nicoletta M. Neuman Angelika M. Kotlarczyk Anna J. Korzekwa 《International journal of molecular sciences》2022,23(23)
The aim of this study was to assess the quality and fertilizing potential of red deer epididymal spermatozoa stored in a liquid state for up to 11 days (D11). In Experiment 1, sperm quality was determined. In Experiment 2, the efficiency of in vitro fertilization (IVF) and artificial insemination (AI) of stored sperm were evaluated. An analysis of sperm quality on D5 of storage revealed a decrease (p < 0.05) in motility and morphology, and a higher proportion of apoptotic spermatozoa. On D1, D7 and D10, the total motility of sperm for IVF and AI was determined to be 82.6%, 71.0% and 64.8%, respectively. The results of IVF and AI demonstrated that the fertilizing potential of spermatozoa differs between days of storage. The percentage of blastocysts was higher when oocytes were fertilized on D1 (17.4 %) compared to D7 (8.5%) and D10 sperm (10.5%). Differences were noted in the pregnancy rates of inseminated hinds. The insemination with D1, D7 and D10 sperm led to live births (33% from D7 and D10). The results indicate that the quality of red deer epididymal spermatozoa remains satisfactory during ten days of storage in a liquid state, and that these spermatozoa maintain their fertility potential. 相似文献
193.
Anna Masek Angelika Plota Julia Chrzastowska Magorzata Piotrowska 《International journal of molecular sciences》2021,22(22)
This study aimed to present the influence of bio-based and anthraquinone dyes and their combinations on the optical properties of ethylene-propylene (EPM) composites after thermo-oxidative and climatic aging. Therefore, the chosen polymer was filled with a natural, plant-origin flavonoid—quercetin, and with two commercial anthraquinone dyes (C.I. Solvent Yellow 163 and C.I. Solvent Red 207). The manufactured polymer composites were subjected to accelerated aging tests: weathering and thermo-oxidation, respectively. Examination of the materials’ properties indicated that the combination of synthetic and natural dyes can result in better resistance to oxidizing agents and higher thermal stability of ethylene-propylene products. Moreover, color change of quercetin-containing samples due to exposure to simulated atmospheric conditions could be a promising solution for use as aging indicators in intelligent packaging materials that will inform about the ongoing degradation process. Another interesting finding is that these samples exhibited good fungistatic activity against Candida albicans yeast and Aspergillus niger mold. Overall, this novel solution based on hybrid polymer composites containing natural and commercial dyes is a more environmentally friendly alternative to traditional materials used in the plastic packaging industry with better and more desirable properties. 相似文献
194.
Joachim Molkentin Ursula Coors Jaap Evers Angelika Miebs 《European Journal of Lipid Science and Technology》2001,103(12):798-803
A German (GE) method and a New Zealand (NZ) method for the direct determination of total fat in spreadable fats were compared in a pilot collaborative study to obtain preliminary information regarding the precision and the level of fat content determined. The study comprised six products, including butter, blended fat products, and margarine with a fat content in the range of 39—82%, and four laboratories. The GE method, based on a Soxhlet extraction using petroleum ether, yielded a repeatability estimate of 0.41 g/100 g and a reproducibility estimate of 0.79 g/100 g. The NZ method, based on an extraction of the fat by thorough shaking of the sample with petroleum ether followed by phase separation, yielded a repeatability estimate of 0.32 g/100 g and a reproducibility estimate of 0.62 g/100 g. The difference in precision estimates between the two methods was significant for repeatability, but not for reproducibility. The better repeatability of the NZ method was probably partly due to the use of a superior sample preparation procedure which ensured that any inhomogeneity developed inside the sample container during transport or storage was removed. The average fat content as determined by the NZ method was 0.20 g/100 g higher than that determined by the GE method, but for individual samples no constant bias was observed. However, an inverse correlation between the bias and the fat content of the product suggested that the anhydrous sodium sulphate used in the GE method interfered with the fat recovery when analysing samples containing a high percentage of water. Thus, according to this study, the NZ method seems to have certain advantages over the GE method with respect to the results obtained. 相似文献
195.
Kamila Ociepa Marian Danilewicz Magorzata Wgrowska-Danilewicz Ra Peterson-Jckowska Angelika Wjcicka-Rubin Natalia Lewkowicz Radosaw Zajdel Agnieszka ebrowska 《International journal of molecular sciences》2023,24(1)
The JAK/STAT signal pathway is a system of intracellular proteins used by many cytokines and growth factors to express genes responsible for the process of cell activation, proliferation and differentiation. There has been numerous inflammatory and autoimmune diseases identified where the JAK/STAT signaling is disrupted; however, there are only a few papers concerning autoimmune bullous diseases published. The aim of this study was to evaluate the expression of proteins: JAK3, STAT2, STAT4 and STAT6 in epithelium lesions in patients with pemphigus vulgaris (PV), bullous pemphigoid (BP), oral lichen planus (LP) and chronic ulcerative stomatitis (CUS), as well as in the control group. Immunohistochemistry and immunoblotting were used to evaluate expression of selected proteins. We found significantly higher expression of selected JAK/STAT proteins in oral mucosa lesions in study groups in comparison to the control group, which indicates participation of JAK/STAT pathway in pathogenesis of these diseases. In BP and PV there were no increased STAT2 expression, whereas in CUS and LP no increased STAT4 expression occurred. The differences in expression of JAK/STAT proteins in selected disorders have been observed. These results create new potential therapeutic targets for the treatment. 相似文献
196.
Johannes Kahl Farnaz Alborzi Alexander Beck Susanne Bügel Nicolaas Busscher Uwe Geier Darja Matt Tabea Meischner Flavio Paoletti Sirli Pehme Angelika Ploeger Ewa Rembiałkowska Otto Schmid Carola Strassner Bruno Taupier‐Letage Aneta Załęcka 《Journal of the science of food and agriculture》2014,94(13):2582-2594
In 2007 EU Regulation (EC) 834/2007 introduced principles and criteria for organic food processing. These regulations have been analysed and discussed in several scientific publications and research project reports. Recently, organic food quality was described by principles, aspects and criteria. These principles from organic agriculture were verified and adapted for organic food processing. Different levels for evaluation were suggested. In another document, underlying paradigms and consumer perception of organic food were reviewed against functional food, resulting in identifying integral product identity as the underlying paradigm and a holistic quality view connected to naturalness as consumers' perception of organic food quality. In a European study, the quality concept was applied to the organic food chain, resulting in a problem, namely that clear principles and related criteria were missing to evaluate processing methods. Therefore the goal of this paper is to describe and discuss the topic of organic food processing to make it operational. A conceptual background for organic food processing is given by verifying the underlying paradigms and principles of organic farming and organic food as well as on organic processing. The proposed definition connects organic processing to related systems such as minimal, sustainable and careful, gentle processing, and describes clear principles and related criteria. Based on food examples, such as milk with different heat treatments, the concept and definitions were verified. Organic processing can be defined by clear paradigms and principles and evaluated according criteria from a multidimensional approach. Further work has to be done on developing indicators and parameters for assessment of organic food quality. © 2013 Society of Chemical Industry 相似文献
197.
Differenzierte Analytik zu den Bindungsformen des Eisens in verschiedenen pflanzlichen Lebensmitteln
Angelika Thiele und Georg Schwedt 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1985,180(2):126-131
Zusammenfassung In vierzehn pflanzlichen Lebensmitteln unterschiedlicher Zusammensetzung wird eine Differenzierung der Eisengehalte nach wasserlöslich, in Essigsäureethylester löslich, labilen Gehalten und Eisen(II)- bzw. Eisen(III)-Spezies im wäßrigen Extrakt mit Hilfe des photometrischen Ferrozin-Verfahrens durchgeführt. Hohe wasserlösliche, labile Eisenanteile und Eisen(II)-Gehalte wurden im Obst, hohe komplexierte Anteile im wäßrigen Extrakt und mit Essigsäureethylester extrahierbare Eisengehalte in proteinreichen Lebensmitteln ermittelt. Die Eisen-Gesamtgehalte liegen zwischen 1 und 90 ppm, die wasserlöslichen Anteile betragen je nach Lebensmittel 6 bis 60% des Gesamtgehaltes.
Differentiated analysis about the binding forms of iron in various plant foodstuffs
Summary In fourteen plant foodstuffs of various composition a differentiation of iron contents according to water soluble, in ethylacetate extractable, in labile contents and iron(II) or Fe(III) species in the water extract are carried out by the spectrophotometric Ferrozine method. High water-soluble labile iron parts and high iron(II) contents were found in fruit, high complexed parts in the water extract and ethylacetate extractable iron contents in protein rich food-stuffs. The iron total contents are situated between 1 and 90 ppm, the water soluble parts amount to 6 up to 60% of the total content according to the food-stuffs.相似文献
198.
Geoffrey Ssepuuya Christof Van Poucke Emmanuel Njumbe Ediage Catherine Mulholland Angelika Tritscher Philippe Verger 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2018,35(7):1384-1393
This research aimed at evaluating the safety, and the type, level and prevalence of mycotoxins in grain sorghum of four sub-Saharan African (SSA) countries (Burkina Faso, Ethiopia, Mali and Sudan). A multi-analyte LC-MS/MS method for quantification of 23 mycotoxins (nivalenol, deoxynivalenol, fusarenon X, neosolaniol, 3-acetyl deoxynivalenol, 15-acetyl deoxynivalenol, diacetoxyscirpenol, roquefortine C, HT-2 toxin, alternariol, T-2 toxin, FB1, FB2, FB3, zearalenone, aflatoxin G1, aflatoxin G2, aflatoxin B1, aflatoxin B2, sterigmatocystin, OTA, altenuene, alternariol monomethylether) was applied to different sorghum matrices. Of the 1533 analysed samples, 33% were contaminated with at least one of the following mycotoxins: aflatoxins, fumonisins, sterigmatocystin, Alternaria toxins, OTA and zearalenone. Country of origin, colour, source and collection period of sorghum samples significantly influenced the type, level and prevalence of mycotoxins. Sterigmatocystin (15%), fumonisins (17%) and aflatoxins (13%) were the most prevalent. FB1 (274 ± 585 µg/kg) had the highest mean concentration followed by FB2 (214 ± 308 µg/kg) while diacetoxyscirpenol (8.12 ± 19.2 µg/kg) and HT-2 (11.9 ± 0.00 µg/kg) had the lowest concentrations. Neosolaniol, fusarenon-X, 3-acetyl deoxynivalenol, 15-acetyl deoxynivalenol, T-2 toxin, nivalenol and roquefortine C were not detected in any of the samples. Sudan had the lowest prevalence and mean concentration of all mycotoxins. Pink sorghum had the highest concentrations of fumonisins and aflatoxins. Mycotoxins from Aspergillus spp. and Alternaria spp. are the mycotoxins of concern in SSA grain sorghum with regard to prevalence, concentration and possible health risk from exposure. Based on the performed risk characterisation, daily consumption of sorghum containing aflatoxins, alternariol, alternariol monomethyl ether, sterigmatocystin and OTA could result in exceeding the established health-based guidance values for these toxins. 相似文献
199.
Armin Mosandl und Angelika Kustermann 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1989,189(3):212-215
Zusammenfassung Durch off-line Kopplung von HPLC und HRGC an Heptakis (3-O-acetyl-2,6-di-O-pentyl)--cyclodextrin als chiraler stationärer Phase gelingt erstmalig die chirospezifische Analyse von 4-alkylsubstituierten-Lactonen aus Fruchtnektaren und verschiedenen fruchthaltigen Zubereitungen des Handels.
Stereoisomere Aromastoffe XXX. HRGC-analysis of chiral-lactones from beverages and fruit-preparations
Summary The first direct chirospecific analysis of 4-alkyl-substituted-lactones from fruit nectars and some other commercially available fruit-containing preparations is reported by off-line coupling of HPLC with HRGC on heptakis (3-O-acetyl-2,6-di-O-pentyl)--cyclodextrin as a suitable chiral stationary phase.相似文献
200.
Daniela Klein Vasileios Gkisakis Angelika Krumbein Ioannis Livieratos Ulrich Köpke 《International Journal of Food Science & Technology》2010,45(11):2250-2257
The influence of two different harvest times (optimal and 4 days earlier) on thirty flavour compounds, titratable acid and sugars as well as consumer acceptance of four old and endangered tomato cultivars (‘Ananas’, ‘Auriga’, ‘Green Zebra’ and ‘Lukullus’) was analysed. In most cases, cultivar type had a greater effect on the volatiles profile than harvest times. Sugar contents were mostly higher at optimal harvest compared with early harvest, whereas acid content was in most cases not affected by harvest time. Consumers perceived differences in several visual and sensory aspects between cultivars as well as harvest times. The optimal harvest was regularly preferred to or at least regarded as equal to the early‐harvest time. Sensory evaluation was poorly related to the aroma volatile profile and only partly to the acid and reducing sugar contents of tomatoes. This was probably owing to the special external characteristics of the tomatoes: differing in size, shape and colour from the ‘normal’ red types. 相似文献