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排序方式: 共有647条查询结果,搜索用时 15 毫秒
31.
Katie M. Dixon Wannit Tongkao-On Vanessa B. Sequeira Sally E. Carter Eric J. Song Mark S. Rybchyn Clare Gordon-Thomson Rebecca S. Mason 《International journal of molecular sciences》2013,14(1):1964-1977
Exposure to sunlight is the major cause of skin cancer. Ultraviolet radiation (UV) from the sun causes damage to DNA by direct absorption and can cause skin cell death. UV also causes production of reactive oxygen species that may interact with DNA to indirectly cause oxidative DNA damage. UV increases accumulation of p53 in skin cells, which upregulates repair genes but promotes death of irreparably damaged cells. A benefit of sunlight is vitamin D, which is formed following exposure of 7-dehydrocholesterol in skin cells to UV. The relatively inert vitamin D is metabolized to various biologically active compounds, including 1,25-dihydroxyvitamin D3. Therapeutic use of vitamin D compounds has proven beneficial in several cancer types, but more recently these compounds have been shown to prevent UV-induced cell death and DNA damage in human skin cells. Here, we discuss the effects of vitamin D compounds in skin cells that have been exposed to UV. Specifically, we examine the various signaling pathways involved in the vitamin D-induced protection of skin cells from UV. 相似文献
32.
Xianfeng Chen Holly J. Corbett Sally R. Yukiko Anthony P. Raphael Emily J. Fairmaid Tarl W. Prow Lorena E. Brown Germain J. P. Fernando Mark A. F. Kendall 《Advanced functional materials》2011,21(3):464-473
Densely packed dry‐coated microprojections are shown to deliver vaccines to targeted locations within the skin that are rich in immune cells, thus inducing protective immune responses against a lethal virus challenge. Selectively limiting the antigen coating to the tips of the projections, which penetrate the skin, would significantly reduce the amount of vaccine required in immunization. In this paper a simple technique, dip‐coating the microprojections, is introduced to meet this goal. By increasing the coating solution viscosity, an otherwise strong capillary action is mitigated and the desired controlled coating length on projections is achieved. Following application to the skin, most of the coated vaccine material is rapidly released from the projections (82.6% in mass within 2 min) to the target locations within the skin strata and a potent immune response is induced when a conventional influenza vaccine (Fluvax) is tested in a mouse model. The utility of this coating approach to a variety of molecules representative of vaccines (e.g., chicken egg ovalbumin (OVA) protein, DNA, and fluorescent dyes) is demonstrated. These collective attributes, together with the simplicity of the approach, position the dip‐coating method for practical utility in large vaccination campaigns. 相似文献
33.
Vivanti Giacomo; McCormick Carolyn; Young Gregory S.; Abucayan Floridette; Hatt Naomi; Nadig Aparna; Ozonoff Sally; Rogers Sally J. 《Canadian Metallurgical Quarterly》2011,47(3):841
Typically developing children understand and predict others' behavior by extracting and processing relevant information such as the logic of their actions within the situational constraints and the intentions conveyed by their gaze direction and emotional expressions. Children with autism have difficulties understanding and predicting others' actions. With the use of eye tracking and behavioral measures, we investigated action understanding mechanisms used by 18 children with autism and a well-matched group of 18 typically developing children. Results showed that children with autism (a) consider situational constraints in order to understand the logic of an agent's action and (b) show typical usage of the agent's emotional expressions to infer his or her intentions. We found (c) subtle atypicalities in the way children with autism respond to an agent's direct gaze and (d) marked impairments in their ability to attend to and interpret referential cues such as a head turn for understanding an agent's intentions. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
34.
Ayman Ben Mabrouk Hamid Kaddami Albert Magnin Mohamed Naceur Belgacem Alain Dufresne Sami Boufi 《Polymer Engineering and Science》2011,51(1):62-70
A one‐step method was used to prepare stable aqueous nanocomposite dispersions based on cellulose whiskers extracted from the rachis of the date palm tree and a poly(styrene‐co‐2‐ethyl hexylacrylate) copolymer via miniemulsion polymerization. A reactive silane, i.e., methacryloxypropyl triethoxysilane was added to stabilize the dispersion and favor the anchoring of the whiskers on polymer particles. Dynamic light scattering was used to study the effect of the silane and whiskers contents on the average particle size of the polymer. Nanocomposites materials were prepared from these dispersions using a casting/evaporation method. The effect of the silane and whiskers contents on the thermal and mechanical properties were studied using differential scanning calorimetry and dynamic mechanical analysis. POLYM. ENG. SCI., 2011. © 2010 Society of Plastics Engineers 相似文献
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Sally Yerkovich 《The Journal of communication》1977,27(1):192-196
40.
Golden Charles J.; Kuperman Sally K.; MacInnes William D.; Moses James A. 《Canadian Metallurgical Quarterly》1981,49(4):606
Cross-validated the use of a short form of the Halstead Category Test as suggested by D. A. Calsyn et al (see record 1981-02450-001). For 60 Ss (mean age 36.72 yrs), it was found that the total score estimated from their formula (based on the 1st 4 subtests of the Category Test) correlated .88 with the overall score. The formula was cross-validated in 3 samples with all correlations above .83. It was found that the formula could reliably predict who would exceed the cutoff of the entire test, with an overall accuracy across the 4 samples of 184 out of 205. (3 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献