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991.
So Yeon Jung Young Eun Kim Won Soon Park So Yoon Ahn Dong Kyung Sung Se In Sung Kyeung Min Joo Seong Gi Kim Yun Sil Chang 《International journal of molecular sciences》2022,23(8)
Severe intraventricular hemorrhage (IVH) remains a major cause of high mortality and morbidity in extremely preterm infants. Mesenchymal stem cell (MSC) transplantation is a possible therapeutic option, and development of therapeutics with enhanced efficacy is necessary. This study investigated whether thrombin preconditioning improves the therapeutic efficacy of human Wharton’s jelly-derived MSC transplantation for severe neonatal IVH, using a rat model. Severe neonatal IVH was induced by injecting 150 μL blood into each lateral ventricle on postnatal day (P) 4 in Sprague-Dawley rats. After 2 days (P6), naïve MSCs or thrombin-preconditioned MSCs (1 × 105/10 μL) were transplanted intraventricularly. After behavioral tests, brain tissues and cerebrospinal fluid of P35 rats were obtained for histological and biochemical analyses, respectively. Thrombin-preconditioned MSC transplantation significantly reduced IVH-induced ventricular dilatation on in vivo magnetic resonance imaging, which was coincident with attenuations of reactive gliosis, cell death, and the number of activated microglia and levels of inflammatory cytokines after IVH induction, compared to naïve MSC transplantation. In the behavioral tests, the sensorimotor and memory functions significantly improved after transplantation of thrombin-preconditioned MSCs, compared to naïve MSCs. Overall, thrombin preconditioning significantly improves the therapeutic potential and more effectively attenuates brain injury, including progressive ventricular dilatation, gliosis, cell death, inflammation, and neurobehavioral functional impairment, in newborn rats with induced severe IVH than does naïve MSC transplantation. 相似文献
992.
993.
A review of research on bridging the gap between formal and informal learning with technology in primary school contexts 下载免费PDF全文
This study reviews empirical research articles published in the field of technology‐enhanced learning in the out‐of‐class contexts in primary schools between the years 2007 and 2016 and explores how the body of research has connected formal and informal learning experiences, referred to in the paper as bridging the gap. The review focuses on 43 selected experiments from 41 research papers, which are in detail examined and classified using the 3 criteria: (a) the Bloom's taxonomy for learning, (b) the intentionality to physical settings classification used to differentiate types of learning in various environments, and (c) the characteristics of seamless learning design. The findings confirm that technology can enhance learning in and out of classroom, especially by impacting student interest, motivation, and engagement. The close examination of the subset of studies with cognitive gains shows that they successfully bridged the gap between learning spaces and that such bridging positively correlates with the number of steps in the learning activity design. The successful bridging of the gap between learning spaces could further benefit from including more online social learning activities into the designed learning process and from involving teachers as cocreators of the learning process and resources. 相似文献
994.
The cooling effects of the lubricating oil supplied to a full journal bearing through two axial feed grooves each at right angles to the load line are studied. The thermohydrodynamic analysis assumes no heat is removed through either the journal or bush. The results show that the oil temperature distribution along the axial direction of the bearing is usually not uniform. Only if the axial length of the feed grooves approaches the bearing length will the temperature in the high pressure zone be uniformly distributed over its axial length. Both the oil supply pressure and the geometry of the feed grooves control the oil supply rate, which determines the cooling effect of the supply oil. Finally, a formula is suggested for the rate of supply flow 相似文献
995.
996.
Lingonberries and their products are popular and generally accessible in Europe, though in the US they are uncommon and considered a minor berry/fruit crop. The on-going interest in potential health benefits from berry consumption has heightened interest in broadening the selection of berry/fruit crops in the US. This study measured total phenolics, total tannins, complete anthocyanin content, and total (and individual) free amino acid composition for each of five lingonberry cultivars. Cultivars Ida, Koralle, Linnea, Sanna, and Sussi were grown in Oregon, USA, and had only been evaluated previously for their horticultural traits. All five cultivars contained the three anticipated anthocyanins (by HPLC): cyanidin-3-galactoside (main anthocyanin found in these berries), cyanidin-3-glucoside, and cyanidin-3-arabinoside. These lingonberries’ total anthocyanin content ranged from 27.4 (‘Linnea’) to 52.6 (‘Ida’) mg/100 g fw. They contained 22 free amino acids (FFAs) and total FAAs ranged from 28.92 (‘Sanna’) to 70.38 (‘Koralle’) mg/100 g fw. Asparagine (ASN) was the leading FAA (22–34% of the total FAAs) for all five cultivars. This is the first report on lingonberry FAA content. 相似文献
997.
998.
Gulkowska A Jiang Q So MK Taniyasu S Lam PK Yamashita N 《Environmental science & technology》2006,40(12):3736-3741
As an initial survey of human exposure to perfluorinated acids through food consumption in China, seven types of seafood collected from fish markets in two coastal cities were analyzed. Nine perfluorinated compounds were determined using HPLC coupled with ESI-MS/MS. Perfluorooctane sulfonate (PFOS) was the predominant fluorochemical and was found in all 27 seafood samples, including fish, molluscs, crabs, shrimp, oysters, mussels, and clams. Concentrations of PFOS in seafood samples ranged from 0.3 to 13.9 ng/g wet weight, with the highest concentration in mantis shrimp. The hazard ratios of noncancer risk through seafood consumption based on PFOS and perfluorooctanoic acid concentrations were calculated and were less than unity. 相似文献
999.
Preparation of highly emissive,thermally stable,UV‐cured polysilsesquioxane/ZnO nanoparticle composites 下载免费PDF全文
A high molecular weight polysilsesquioxane (LPMSQ)/ZnO nanocomposite was prepared by blending a methacryl‐substituted polysilsesquioxane and PMMA‐coated ZnO nanoparticle (NP) followed by UV‐curing process. These LPMSQ/ZnO nanocomposites gave high thermal and mechanical stabilities originated from the rigid ladder structured siloxane backbone of LPMSQ. The polysilsesquioxane and surface‐modified ZnO nanoparticles showed excellent compatibility between MMA groups in LPMSQ‐ and PMMA‐capped ZnO nanoparticles to give well‐dispersed LPMSQ/ZnO nanocomposites. Mechanically pliant and flexible free standing films were obtained, and the photo and optical properties of these hybrid nanocomposites were examined. The high photoluminescent properties were maintained even after severe thermal treatments exceeding 400°C. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42333. 相似文献
1000.
Sándor Soós 《Scientometrics》2014,98(1):23-51
In science mapping, bibliographic coupling (BC) has been a standard tool for discovering the cognitive structure of research areas, such as constituent subareas, directions, schools of thought, or paradigms. Modelled as a set of documents, research areas are often sorted into document clusters via BC representing a thematic unit each. In this paper we propose an alternative method called age-sensitive bibliographic coupling: the aim is to enable the standard method to produce historically valid thematic units, that is, to yield document clusters that represent the historical development of the thematic structure of the subject as well. As such, the method is expected to be especially beneficial for investigations on science dynamics and the history of science. We apply the method within a bibliometric study in the modern history of bioscience, addressing the development of a complex, interdisciplinary discourse called the Species Problem. As a result, a quantitative and qualitative comparison of the standard and the proposed method of bibliographic coupling will be reported, together with a pilot study on the cognitive–historical structure of the Species Problem, regarding an important fragment of the discourse. 相似文献