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排序方式: 共有1110条查询结果,搜索用时 15 毫秒
141.
Sandra Smiljanic Cyril Messaraa Virginie Lafon-Kolb Nina Hrapovic Nahid Amini Christina Osterlund Lene Visdal-Johnsen 《International journal of molecular sciences》2022,23(20)
The Scandinavian region is home to a unique biome with endemic plant species. The aim of this study was to explore this natural diversity and identify plant extracts providing positive skin barrier effects. Six plant extracts were identified as starting material. Following biochemical screening, two candidates outperformed the rest: Betula alba (BA) and Empetrum nigrum (EN). Quantitative PCR analysis showed that BA and EN upregulated barrier genes, when used individually and in combination. Betula alba increased AQP3 and OCLN protein expression, something niacinamide was incapable of. Additionally, the skin barrier was strengthened, evidenced by inhibition of KLK5 and hyaluronidase and showed strong antioxidant and anti-inflammatory activity through DPPH and COX2 inhibition, respectively. A first split-face clinical study was conducted using the combination of extracts versus placebo. There was a significantly better skin restructuring effect and corneocyte cohesion on the side treated with combined extracts. A second split-face clinical study assessed the combined extracts versus 3% niacinamide. Significant variations in skin hydration and TEWL were observed in favor of the extract treated side. In conclusion, we identified a natural alternative to niacinamide for improving skin barrier health, in Scandinavian plant extracts, which yield strong performance, but at a lower concentration. 相似文献
142.
Cancer stem cells (CSC) play one of the crucial roles in the pathogenesis of various cancers, including colorectal cancer (CRC). Although great efforts have been made regarding our understanding of the cancerogenesis of CRC, CSC involvement in CRC development is still poorly understood. Using bioinformatics and RNA-seq data of normal mucosa, colorectal adenoma, and carcinoma (n = 106) from GEO and TCGA, we identified candidate CSC genes and analyzed pathway enrichment analysis (PEI) and protein–protein interaction analysis (PPI). Identified CSC-related genes were validated using qPCR and tissue samples from 47 patients with adenoma, adenoma with early carcinoma, and carcinoma without and with lymph node metastasis and were compared to normal mucosa. Six CSC-related genes were identified: ANLN, CDK1, ECT2, PDGFD, TNC, and TNXB. ANLN, CDK1, ECT2, and TNC were differentially expressed between adenoma and adenoma with early carcinoma. TNC was differentially expressed in CRC without lymph node metastases whereas ANLN, CDK1, and PDGFD were differentially expressed in CRC with lymph node metastases compared to normal mucosa. ANLN and PDGFD were differentially expressed between carcinoma without and with lymph node metastasis. Our study identified and validated CSC-related genes that might be involved in early stages of CRC development (ANLN, CDK1, ECT2, TNC) and in development of metastasis (ANLN, PDGFD). 相似文献
143.
Kerstin A. Kessel Christian Bohn Uwe Engelmann Dieter Oetzel Nina Bougatf Rolf Bendl Jürgen Debus Stephanie E. Combs 《Computer methods and programs in biomedicine》2014
In radiation oncology, where treatment concepts are elaborated in interdisciplinary collaborations, handling distributed, large heterogeneous amounts of data efficiently is very important, yet challenging, for an optimal treatment of the patient as well as for research itself. This becomes a strong focus, as we step into the era of modern personalized medicine, relying on various quantitative data information, thus involving the active contribution of multiple medical specialties. Hence, combining patient data from all involved information systems is inevitable for analyses. Therefore, we introduced a documentation and data management system integrated in the clinical environment for electronic data capture. We discuss our concept and five-year experience of a precise electronic documentation system, with special focus on the challenges we encountered. We specify how such a system can be designed and implemented to plan, tailor and conduct (multicenter) clinical trials, ultimately reaching the best clinical performance, and enhancing interdisciplinary and clinical research. 相似文献
144.
Are financial incentives related to performance? A meta-analytic review of empirical research. 总被引:1,自引:0,他引:1
Jenkins G. Douglas Jr.; Mitra Atul; Gupta Nina; Shaw Jason D. 《Canadian Metallurgical Quarterly》1998,83(5):777
The relationship of financial incentives to performance quality and quantity is cumulated over 39 studies containing 47 relationships. Financial incentives were not related to performance quality but had a corrected correlation of .34 with performance quantity. Setting (laboratory, field, experimental simulation) and theoretical framework moderated the relationship, but task type did not. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
145.
The latent trait-state-error model (TSE) and the latent state-trait model with autoregression (LST-AR) represent creative structural equation methods for examining the longitudinal structure of psychological constructs. Application of these models has been somewhat limited by empirical or conceptual problems. In the present study, Monte Carlo analysis revealed that TSE models tend to generate improper solutions when N is too small, when waves are too few, and when occasion factor stability is either too large or too small. Mathematical analysis of the LST-AR model revealed its limitation to constructs that become more highly auto-correlated over time. The trait-state-occasion model has fewer empirical problems than does the TSE model and is more broadly applicable than is the LST-AR model. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
146.
Nina V. Krainyukova 《Thin solid films》2006,515(4):1658-1663
Calculations of the energetics of multiply twinned particles (MTPs) such as icosahedra and decahedra with fivefold symmetry as well as face-centered cubic (fcc) and hexagonal close-packed (hcp) particles in the size interval from 13 up to ∼ 45,000 atoms were made applying Lennard-Jones potentials. We essentially extended the size interval comparatively with previous studies and included shape-optimized hcp clusters in the global energy analysis that gives rise to the new insight into the basic fcc/hcp problem. For the cluster size N from minimal up to N ∼ 2000 atoms the binding energy is highest for icosahedra, in the size interval from 2000 up to ∼ 11,500 atoms decahedra prevail, above N ∼ 11,500 atoms decahedra and optimized fcc clusters were found to alternate. The hcp structure was revealed to become favorable above N ∼ 34,000 atoms. Thus, hcp clusters can attain their preference with respect to MTPs (comprising fcc fragments) and optimized fcc clusters only for very large sizes. The comparison with several other models is suggested and the opportunity of experimental observations is discussed. 相似文献
147.
148.
Examined the development of children's motivations to socially compare in a situation in which they were free to seek or not seek information about how another child was doing. 16 males and 16 females each at the kindergarten, 1st, and 2nd grade levels were recruited through the newspaper and paid to participate. Pairs of Ss in the same grade worked on a speed task under high- and low-competition conditions. The frequency and duration with which Ss pushed a button to observe their partner's progress on a monitor was the index of the strength of motivation. Results show the expected developmental increase in comparison behavior. Only in 2nd graders did the expected positive relationship between level of competition and performance appear. At the kindergarten level, the means were in the opposite direction, while for the 1st-grade level the relation between competition and performance depended on sex. Results are discussed in terms of alternative predictions derived from theories by L. Festinger (1954) and J. Veroff (1969). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
149.
Video-enhanced microscopy combined with the use of a computer frame memory extends considerably the useful range of our video enhanced contrast (AVEC) methods for polarizing, double-beam interference and differential interference contrast microscopy. Increased visual contrast is achieved by two stages of amplifications: the first optical, by using high bias retardation settings, and the second electronic. These steps are followed by a reduction of background brightness by means of a clamp voltage applied to a DC restoration circuit of the video camera. One of the limitations of the AVEC method alone is the inevitable appearance under high gain conditions of a pattern of mottle due to inaccessible dirt and defects in the lenses even of high quality. This limitation has been circumvented by storing the mottle pattern in the frame memory (frame store) and continuously subtracting it from each succeeding frame to clear the image. A major gain in image quality has resulted. In polarizing microscopy, the frame memory can be used also to subtract the image at one compensator setting from that at the equivalent setting of opposite sign, thus removing from the final image not only most of the mottle pattern but also the contrast due to the bright-field contrast. In the polarizing microscope, these manipulations of the raw video image make it possible to observe and measure the birefringence of various organelles and elements such as microtubules, intermediate filaments and bundles of as few as a half dozen actin filaments. Since scattered light is also removed from the image, features hidden from view in the unprocessed image become visible. In differential interference microscopy, the AVEC method makes visible (i.e. detectable) many linear elements and particles that are an order of magnitude smaller than the resolution limit and not visible in the optical image. Such features are inflated by diffraction, however, to Airy disk size. 相似文献
150.
Examined the development of an awareness (metamemory) of "constructive interference." This is the "fact" that when children and adults are presented a list of semantically related sentences, they later find it more difficult to distinguish old from new instances than when they are presented a list of unrelated sentences. Knowledge of this constructive interference was tested by having 192 11-, 15- and 22-yr-old students first predict recognition and then take an actual recognition test. In independent groups, half of the Ss received lists of semantically related sentences, and half received lists of semantically unrelated sentences. By comparing Ss' predictions with their actual performances across the different groups, it appears that the 11-yr-olds did not comprehend this phenomenon, but the 15- and 22-yr-olds did. That is, older Ss correctly predicted that recognition performance would be poorer for related lists than for unrelated lists. The 11-yr-olds, by contrast, predicted that recognition would be about the same for the 2 kinds of lists. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献