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21.
Kanter Jonathan W.; Rusch Laura C.; Landes Sara J.; Holman Gareth I.; Whiteside Ursula; Sedivy Sonja K. 《Canadian Metallurgical Quarterly》2009,46(2):220
To improve cognitive and behavioral therapies (CBT) for depression, several approaches recommend an increased focus on the occurrence of problems as they occur in the therapeutic relationship or in relation to the live therapy process, referred to as present-focused. A lingering question has been the degree to which CBT therapists already engage in present-focused work. This study utilized sessions from recent trials of CBT for depression and, in Phase I, raters identified present-focused interventions on a turn-by-turn basis. Phase II raters used a qualitative analysis to determine categories of present-focused interventions. Results indicated that therapists rarely focused on the therapeutic relationship; when they did, it was often transient and lacking in the elaborations suggested by newer approaches. Therapists more often performed therapy process and emotion focused interventions, but these also tended to lack elaboration. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
22.
Tunable Quantum Confinement in Ultrathin,Optically Active Semiconductor Nanowires Via Reverse‐Reaction Growth
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Shen Li Matthias Zenkel Friedrich E. Kruse Andreas Gießl Ursula Schltzer-Schrehardt 《International journal of molecular sciences》2022,23(7)
Given their vital role in the homeostasis of the limbal stem cell niche, limbal melanocytes have emerged as promising candidates for tissue engineering applications. This study aimed to isolate and characterize a population of melanocyte precursors in the limbal stroma, compared with melanocytes originating from the limbal epithelium, using magnetic-activated cell sorting (MACS) with positive (CD117/c-Kit microbeads) or negative (CD326/EpCAM or anti-fibroblast microbeads) selection approaches. Both approaches enabled fast and easy isolation and cultivation of pure limbal epithelial and stromal melanocyte populations, which differed in phenotype and gene expression, but exhibited similar functional properties regarding proliferative potential, pigmentation, and support of clonal growth of limbal epithelial stem/progenitor cells (LEPCs). In both melanocyte populations, limbus-specific matrix (laminin 511-E8) and soluble factors (LEPC-derived conditioned medium) stimulated melanocyte adhesion, dendrite formation, melanogenesis, and expression of genes involved in UV protection and immune regulation. The findings provided not only a novel protocol for the enrichment of pure melanocyte populations from limbal tissue applying easy-to-use MACS technology, but also identified a population of stromal melanocyte precursors, which may serve as a reservoir for the replacement of damaged epithelial melanocytes and an alternative resource for tissue engineering applications. 相似文献
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Benno F. Zimmermann Ursula Woelwer-Rieck Menelaos Papagiannopoulos 《Food Analytical Methods》2012,5(2):266-271
Stevia rebaudiana Bertoni contains several steviol glycosides with sweet flavour. They all are sweeter than sucrose (up to factor 450). The
various steviol glycosides are difficult to separate by reversed-phase chromatography. In this paper, five different hydrophilic
liquid interaction chromatography columns are characterized using isocratic elution (5–20% water in acetonitrile with buffer
or formic acid). Separation of the steviol glycosides is possible with all but one of the tested columns, but the robustness
of the separation against changes of buffer concentration and percentage of water differ. Aqueous percentage and ion strength
of the eluent are the main factors to be optimized in method development. 相似文献
27.
I. Kruse Ursula Wolfensberger Raphael Badoud K. Eichner 《European Food Research and Technology》1997,205(1):31-38
The formation of CO2 in tomato powder, chosen as an example of a dry culinary product, was investigated at room temperature and at low values
of water activity (a
w). CO2 formation correlated well with parameters that represent the beginning and progression of the Maillard reaction. In the absence
of O2, CO2 formation decreased. Pectin and depolymerized pectin did not influence CO2 formation while galacturonic acid (GalA) had a large effect. Determination of 13CO2 in low-moisture model systems revealed that CO2 was not formed by decarboxylation of GalA alone. Only a small proportion of [1-13C]glycine and GalA was degraded by the Strecker pathway; however, glucose reacted with the labelled amino acid forming 13CO2 which amounted to over 90% of the total CO2 formed. Therefore, CO2 could be used as an early indicator for the beginning of the Maillard reaction in dry culinary products.
Received: 28 October 1996 相似文献
28.
Pappier U Fernández Pinto V Larumbe G Vaamonde G 《International journal of food microbiology》2008,125(2):153-157
Incidence of fungal contamination of quinoa seeds from three locations (Salar de Uyuni, Bolivia; Salta and Tucumán provinces, Argentina) was analyzed in samples with and without treatment to remove saponins (wet method). In processed samples, the percentage of infection was reduced. Distribution of the different fungal genera was not homogeneous in the three locations (p<0.05), although Penicillium and Aspergillus were the most prevalent contaminants, regardless the geographic origin of the samples. Other genera, such as Eurotium, Fusarium, Phoma, Ulocladium, Mucor and Rhizopus were less frequently isolated. Absidia, Alternaria, Cladosporium, Dreschlera, Epicoccum and Monascus were sporadically encountered. Significant differences (p<0.05) in the distribution of fungal genera in samples with and without saponins from each location were observed. In all cases, processing caused a decrease of Aspergillus incidence, while increased the proportion of Penicillium, Eurotium, Mucor and Rhizopus indicating that these genera were part of the internal mycota. A. flavus and A. niger were the dominating species of genus Aspergillus. A similar pattern of prevalent Penicillium species was observed in samples with and without saponins, since P. aurantiogriseum, P.chrysogenum, P. citrinum and P. crustosum were always present in high number, although their relative density was variable according to the geographic origin of samples. Mycotoxin-producing ability of most representative species was also determined. Toxigenic strains of A. flavus (aflatoxins and cyclopiazonic acid), A. parasiticus (aflatoxins), P. citrinum (citrinin) and P. griseofulvum (cyclopiazonic acid) were found. None of the A. niger isolates was ochratoxin A producer. The above mentioned mycotoxins were not detected in the samples analyzed. 相似文献
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Alicja Tymczewska Bliss Ursula Furtado Jacek Nowaczyk Katarzyna Hrynkiewicz Aleksandra Szydowska-Czerniak 《International journal of molecular sciences》2022,23(5)
This study aimed to develop and characterize gelatin/polyvinyl alcohol (G/PVA) films loaded with black cumin cake extract (BCCE) and zinc oxide nanoparticles (ZnONPs). The BCCE was also applied for the green synthesis of ZnONPs with an average size of less than 100 nm. The active films were produced by a solvent-casting technique, and their physicochemical and antibacterial properties were investigated. Supplementation of G/PVA film in ZnONPs decreased the tensile strength (TS) from 2.97 MPa to 1.69 MPa. The addition of BCCE and ZnONPs increased the elongation at the break (EAB) of the enriched film by about 3%. The G/PVA/BCCE/ZnONPs film revealed the lowest water vapor permeability (WVP = 1.14 × 10−9 g·mm·Pa−1·h−1·mm−2) and the highest opacity (3.41 mm−1). The QUick, Easy, New, CHEap and Reproducible (QUENCHER) methodologies using 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis(3-ethylbenzothiazoline-6- sulfonic acid) (ABTS) and cupric ion reducing antioxidant capacity (CUPRAC) were applied to measure antioxidant capacity (AC) of the prepared films. The incorporation of BCCE and ZnONPs into G/PVA films enhanced the AC by 8–144%. The films containing ZnONPs and a mixture of BCCE and ZnONPs inhibited the growth of three Gram-positive bacterial strains. These nanocomposite films with desired functional properties can be recommended to inhibit microbial spoilage and oxidative rancidity of packaged food. 相似文献
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