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排序方式: 共有1618条查询结果,搜索用时 60 毫秒
81.
Washington Lindsay A.; Wilson Sylia; Engel Joyce M.; Jensen Mark P. 《Canadian Metallurgical Quarterly》2007,52(2):241
Objective: To develop and evaluate a new pediatric measure of community integration: the Pediatric Community Participation Questionnaire (PCPQ). Participants: 105 youths with physical disabilities. Measures: In addition to the PCPQ, demographic and disability-related questions and the Functional Disability Inventory (FDI) were administered. Results: The PCPQ demonstrated convergent validity through its high association with functional ability, discriminant validity through its ability to discriminate between ambulatory and nonambulatory participants, and excellent internal consistency. Conclusions: Community participation, an important component of positive overall development, may be particularly important for youths with physical disabilities. The findings from this study provide preliminary support for the validity and reliability of the PCPQ, supporting its use as a measure of community participation with this population. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
82.
The contribution of prior knowledge in prediction of change in food crop prices using ordinary linear regression (OLR) and Gaussian process (GP) based on a probabilistic approach in famine predictions was established in this study. Prior information was obtained from previous results and incorporated into a new dataset. For GP, both approaches incorporating weight-space view and function-space view were applied and results compared. The function-space view produced a more suitable model than the weight-space view and OLR. Probabilistic inference showed better famine prediction accuracy than the conventional inference approach. Addition of prior information into the prediction framework improved prediction. It is recommended that in addition to the developed model, further modeling should be carried out to include the effects of variables such as bumper harvest, availability of inexpensive alternative foodstuffs for consumption, imported foodstuffs to remedy famine, effect of neighborhood price, and cross-border trade. 相似文献
83.
CD Spies J Herpell O Beck C Müller F Pragst S Borg A Helander 《Canadian Metallurgical Quarterly》1999,17(1):19-27
Interactions among growth factors are important in a variety of physiological and pathological processes. The regulation of IGF-I mRNA expression by bFGF was investigated in cultured rat Müller cells and the mechanism of regulation studied. Müller cells from 1- to 3-day-old Sprague-Dawley rats were isolated and cultured with Eagle MEM+10% FCS. Cultured cells were identified by immunocytochemistry using antibodies against vimentin, carbonic anhydrase C, and glutamine synthetase. Cells of passage 1-4 were treated with bFGF, the PKC inhibitor H-7, calphostin C, the PKC activator PMA or the PKA inhibitor H-89, as well as the adenylate cyclase activator forskolin, or adenylate cyclase inhibitor SQ22536. IGF-I and bFGF expression levels were assessed by Northern blot analysis. The addition of bFGF to culture medium down-regulated IGF-I expression in a dose- and time-dependent manner. Decrease of IGF-I expression started at a bFGF concentration of 1 ng ml-1. IGF-I mRNA level declined to 44% of baseline level at 10 ng ml-1 of bFGF, and reached a trough of 40% at 50 ng ml-1. At 10 ng ml-1 of bFGF, down-regulation of IGF-I expression was observed as early as 4 hr (60%) after treatment, and reached a trough of 42% by 8 hr. The temporal and concentration dependence of IGF-I expression by addition of the PKC activator PMA, to culture medium was similar to that due to the addition of bFGF. The down-regulation of IGF-I expression by bFGF (10 ng ml-1) and PMA (0.1 microM) was blocked by the PKC inhibitors H-7 (30 microM) and calphostin C (1 microM). Forskolin (5 microM), an adenylate cyclase activator, had activator, had no effect on IGF-I expression. SQ22536 (100 microM), an adenylate cyclase inhibitor, and H-89, a PKA inhibitor, had no inhibitory effect on bFGF-induced down-regulation of IGF-I expression. These results indicate that bFGF down-regulates IGF-I expression in cultured rat M uller cells through PKC activation. 相似文献
84.
85.
S De Marino M Iorizzi F Zollo L Minale CD Amsler BJ Baker JB McClintock 《Canadian Metallurgical Quarterly》1997,60(10):959-966
A total of 19 steroids, of which 13 steroidal oligoglycosides (nine new and four known) and six polyhydroxylated steroids (four new and two known), has been isolated from the Antarctic starfish Acodontaster conspicuus. The mixture is dominated by glycosides composed of steroidal aglycons having the hydroxyl groups typically disposed on one side of the tetracyclic nucleus, i.e., 3 beta,4 beta,6 alpha,8,15 beta-, with some having a sulfate at C-6, and differing in the side chains and/or in the disaccharide moieties that are usually attached at C-26, with some at C-28 and C-29. Those compounds are accompanied by minute amounts of glycosides with a delta 8(14)-double bond in the steroid, which is a structural feature not previously found among polyhydroxysteroids derived from starfish. Small amounts of six related unglycosidated polyhydroxysteroids and three higher-molecular-weight asterosaponins complete the composition of the mixture. The structures of the new compounds were determined by interpretation of their spectral data and by comparison with spectral data of known compounds. Eighteen of these compounds were evaluated for their ability to inhibit growth in Antarctic marine bacteria isolated from either the water column or the surfaces of benthic marine invertebrates. Of these compounds, 50% were active against at least one Antarctic marine bacterium. This suggests that these compounds may play an important role in deterring microbial fouling. 相似文献
86.
87.
Bernhard J.T. Kiely E. Washington G. 《Antennas and Propagation, IEEE Transactions on》2001,49(4):597-601
Experimental results are presented on a tunable mechanically actuated microstrip antenna with a parasitic director. A novel piezoelectric actuation system is used to vary dynamically the mechanical displacement of the parasitic element. The center frequency, bandwidth, and antenna gain change as a function of variable spacing between the driven and parasitic elements. In light of the experimental results, smart antenna tuning methods that use mechanical and electrical methods are compared and directions for future work are discussed 相似文献
88.
89.
Kathryn M. L. Taylor-Pashow Thomas B. Peters Fernando F. Fondeur Aaron L. Washington II David T. Hobbs 《分离科学与技术》2015,50(18):2853-2865
The Defense Waste Processing Facility (DWPF), responsible for vitrifying high-level waste (HLW) at the Savannah River Site (SRS), is planning to introduce glycolic acid as a reductant during chemical conditioning of the waste prior to vitrification. A portion of this glycolic acid may be recycled back to the tank farm as sodium glycolate. Since glycolate can serve as a complexing agent for a variety of metallic ions, recent studies were performed to examine the effect of glycolate on the removal of Sr and actinides by monosodium titanate (MST) and modified MST (mMST) and the separation of Cs by the caustic-side solvent extraction (CSSX) process. 相似文献
90.
Barbara Geusens Mireille Van Gele Sien Braat Stefaan C. De Smedt Marc C. A. Stuart Tarl W. Prow Washington Sanchez Michael S. Roberts Niek N. Sanders Jo Lambert 《Advanced functional materials》2010,20(23):4077-4090
The extent to which nanoscale‐engineered systems cross intact human skin and can exert pharmacological effects in viable epidermis is controversial. This research seeks to develop a new lipid‐based nanosome that enables the effective delivery of siRNA into human skin. The major finding is that an ultraflexible siRNA‐containing nanosome—prepared using DOTAP, cholesterol, sodium cholate, and 30% ethanol—penetrates into the epidermis of freshly excised intact human skin and is able to enter into the keratinocytes. The nanosomes, called surfactant‐ethanol‐cholesterol‐osomes (SECosomes), show excellent size, surface charge, morphology, deformability, transfection efficiency, stability, and skin penetration capacity after complexation with siRNA. Importantly, these nanosomes have ideal characteristics for siRNA encapsulation, in that the siRNA is stable for at least 4 weeks, they enable highly efficient transfection of in vitro cultured cells, and are shown to transport siRNA delivery through intact human skin where changes in the keratinocyte cell state are demonstrated. It is concluded that increasing flexibility in nanosomes greatly enhances their ability to cross the intact human epidermal membrane and to unload their payload into targeted epidermal cells. 相似文献