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排序方式: 共有231条查询结果,搜索用时 15 毫秒
81.
Berner Janet B.; Duke Anna V.; Guillory Nancy S.; Oe Emily N. 《Canadian Metallurgical Quarterly》1994,3(2):63
This article summarizes a presentation given during the Tenth Annual Play Therapy Conference in Atlanta, Georgia. The purpose was to correlate the relationship between keynote addresses at APT Conferences over the past decade and the continuing development of play therapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
82.
M Frey R von K?nel-Christen V Stalder-Navarro PJ Duke ER Weibel H Hoppeler 《Canadian Metallurgical Quarterly》1997,167(7):494-501
Quantitative changes in lung, heart and muscle structure were assessed in mice exposed for 14 weeks to a gravitational field of 3 G since the age of 4 weeks; matched controls were kept at normal gravity (1 G). The body mass of 3-G-exposed mice was significantly reduced by 9%, while total skeletal muscle mass remained the same fraction of body mass. The mass of the soleus muscle was found to be significantly larger in 3-G-exposed mice both in absolute (+27%) and body mass specific terms (+42%). Capillary density was significantly reduced by 22% because of a relatively larger increase of fiber cross-sectional area (+47%) than of capillary to fiber ratio (+16%). Other morphometric variables remained unchanged with hypergravity. Heart mass and mitochondrial volume were both larger in 3-G-exposed mice (+15% and +27%, respectively). This difference reached statistical significance when normalized to body mass. The only significant difference in lung structure detectable by morphometric methods were a smaller volume (-9%), that paralleled lower body mass, and thinner alveolar septa (-12%). From these results it is concluded that the lung's support structures in mice are sufficiently strong to withstand the stress of long-term hypergravity; however, 3-G exposure leads to a selective hypertrophy of soleus muscle fibers while absolute capillary length in this muscle remains unaltered. 相似文献
83.
RP Leon T Hedlund SJ Meech S Li J Schaack SP Hunger RC Duke J DeGregori 《Canadian Metallurgical Quarterly》1998,95(22):13159-13164
Although adenovirus can infect a wide range of cell types, lymphocytes are not generally susceptible to adenovirus infection, in part because of the absence of the expression of the cellular receptor for the adenoviral fiber protein. The cellular receptor for adenovirus and coxsackievirus (CAR) recently was cloned and shown to mediate adenoviral entry by interaction with the viral fiber protein. We show that the ectopic expression of CAR in various lymphocyte cell lines, which are almost completely resistant to adenovirus infection, is sufficient to facilitate the efficient transduction of these cells by recombinant adenoviruses. Furthermore, this property of CAR does not require its cytoplasmic domain, consistent with the idea that CAR primarily serves as a high affinity binding site for the adenoviral fiber protein, and that viral entry is mediated by interaction of the viral penton base proteins with cellular integrins. As a demonstration of their functional utility, we used CAR-expressing lymphocytes transduced with an adenovirus expressing Fas ligand to efficiently kill Fas receptor-expressing tumor cells. The ability to efficiently manipulate gene expression in lymphocyte cells by using adenovirus vectors should facilitate the functional characterization of pathways affecting lymphocyte physiology. 相似文献
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OBJECTIVE: To emphasize a potentially lethal condition that is virtually impossible to diagnose preoperatively. DESIGN: Case report with review of the literature. SETTING: University Hospital. PARTICIPANT: The patient requiring urgent surgery for heart failure related to severe aortic stenosis and mild mitral stenosis with poor ventricular function. The patient was elderly and suffered from atrial fibrillation. INTERVENTIONS: Preoperative transesophageal echocardiography followed by mitral valve repair and aortic valve replacement. MEASUREMENTS: Clinical outcome and pathological results. RESULTS: Although preoperative TEE demonstrated no left atrial appendage abnormality. After cardiac manipulation prior to the institution of cardiopulmonary bypass a large left atrial mural thrombus was mobilized from the atrial wall and was free floating in the left atrium. CONCLUSIONS: For high risk patients TEE should be applied intraoperatively to avoid undiagnosed left atrial clot dislodgement. 相似文献
86.
BO Duke 《Canadian Metallurgical Quarterly》1981,283(6298):1036-1037
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Sandow Mark Yidana Duke Ophori Bruce Banoeng-Yakubo 《Canadian Metallurgical Quarterly》2008,134(2):222-227
Groundwater is the most widely used water resource in the Afram Plains area, Ghana. The objective of this study was to determine the distribution of fluoride, sodium adsorption ratio (SAR), and salinity (EC) in groundwater from the different aquifers in the Afram Plains area. The distribution of these parameters would enable a determination of the quality of groundwater from the different aquifer units for use in households and irrigation purposes. The inverse distance weighting, interpolator with a power of 2 was applied to 143 data points of each parameter to generate prediction maps for fluoride, SAR, and EC in the area. The distribution maps from this study show that the shale aquifers that underlie the southwestern sections of the area have the highest levels of fluoride, SAR, and EC. A narrow strip of the shale aquifer in the southwestern region produces groundwater whose fluoride level (2.2?mg/L) is higher than the World Health Organization minimum allowable fluoride concentration of 1.5?mg/L in drinking water. The feldsparthic sandstone, arkose, siltstone, and mudstone aquifers in the northeastern sections of the area produce groundwater with fluoride concentration in the range of 0.0–0.3?mg/L, which fall outside the minimum range of 0.7–1.2?mg/L required in drinking water for normal bone and dental health. The highest SAR and EC are also associated with the shale aquifers to the southwestern section of the area. Using the World Food and Agriculture Organization’s guidelines for irrigation water quality, it was determined that groundwater from the Afram Plains area will generally have a mild to moderate effect on the hydraulic properties of soils when used as irrigation water. 相似文献
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