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Helene N. Guttman Boris Weinstein Rita M. Bartschot Peter S. Tam 《Cellular and molecular life sciences : CMLS》1975,31(3):285-288
Zusammenfassung Eine Synthese von Scotophobin mit klassischen Methoden ergab ein Produkt, das sich vom natürlichen Peptid hinsichtlich seiner biologischen, chromatographischen und physiologischen Eigenschaften unterschied. Es wird daraus gefolgert, dass die für das natürliche Produkt vorgeschlagene Strukturformel nicht korrekt ist. 相似文献
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对原型双跨复合梁的结构行为给出了详细的有限元研究.由于基本上认为剪切连接件是非刚性的,在高等有限元模型中采用弹簧单元可以将它们的非线性荷载一滑移性质考虑在内.对各种原型双跨复合梁进行了参数研究,并提出了主要的研究结果.主要的结构参数包括剪切连接件在正弯矩和负弯矩区域内的变形韧性和变形程度.总共比较和讨论了9个具有不同类型和剪切件数目的复合梁的结构行为,对目前的设计缺陷进行了鉴定.由于提出的有限元模型对详细调查复合梁的结构行为非常有效,有效地利用所提出的模型将对更具有改善结构精度和效率的细化设计准则的发展有帮助. 相似文献
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HAb18G/CD147-mediated calcium mobilization and hepatoma metastasis require both C-terminal and N-terminal domains 总被引:4,自引:0,他引:4
Jiang JL Chan HC Zhou Q Yu MK Yao XY Lam SY Zhu H Ho LS Leung KM Chen ZN 《Cellular and molecular life sciences : CMLS》2004,61(16):2083-2091
HAb18G/CD147 is a heavily glycosylated protein containing two immunoglobulin superfamily domains. Our previous studies have indicated that overexpression of HAb18G/CD147 enhances metastatic potentials in human hepatoma cells by disrupting the regulation of store-operated Ca2+ entry by nitric oxide (NO)/cGMP. In the present study, we investigated the structure-function of HAb18G/CD147 by transfecting truncated HAb18G/CD147 fragments into human 7721 hepatoma cells. The inhibitory effect of HAb18G/CD147 on 8-bromo-cGMP-regulated thapsigargin-induced Ca2+ entry was reversed by the expression of either C or N terminus truncated HAb18G/CD147 in T7721C and T7721N cells, respectively. The potential effect of HAb18G/CD147 on metastatic potentials, both adhesion and invasion capacities, of hepatoma cells was abolished in T7721C cells, but not affected in T7721N cells. Release and activation of matrix metalloproteinases (MMPs), MMP-2 and MMP-9, were found to be enhanced by the expression of HAb18G/CD147, and this effect was abolished by both truncations. Thapsigargin significantly enhanced release and activation of MMPs (MMP-2 and MMP-9) in non-transfected 7721 cells, and this effect was negatively regulated by SNAP. However, no effects of thapsigargin or SNAP were observed in T7721 cells, and expression of HAb18G/CD147 enhanced secretion and activation of MMPs at a stable and high level. Taken together, these results suggest that both ectodomain and intracellular domains of HAb18G/CD147 are required to mediate the effect of HAb18G/CD147 on the secretion and activation of MMPs and metastasis-related processes in human hepatoma cells by disrupting the regulation of NO/cGMP-sensitive intracellular Ca2+ mobilization although each domain may play different roles.Received 1 April 2004; received after revision 15 June 2004; accepted 22 June 2004 相似文献
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Pressure garments constructed with elastic fabric play an important role in burn rehabilitation by helping to prevent or reduce the formation of hypertrophic scars. For clinical effectiveness, these garments are made in appropriate size for individual patient in order to provide an appropriate amount of skin-and-garment interface pressure on the patient.The seam area of pressure garments has marked impact on the comfort and durability of the pressure garments.Comments from the patients and occupational therapists have indicated that discomfort arose in the seam zone.Line marks appeared on the skin of patients under the seamed areas of pressure garments. This may be caused by uneven or Iocalised interface pressure at the seamed area. In this paper, the changes of interface pressure between the seamed and unseamed areas were investigated. The aim is to provide an understanding of the effect of seams on the interface pressure in order to assist the therapists and/or garment makers to choose an appropriate s 相似文献
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This paper studies on fabrics suitable for child patients'garment in the hospital environment in Hong Kong,China.Subjective measurement was carried out by questionnaire survey to consult medical staff on hospital requirement about fabric criteria for child patients' garment. On the other hand, objective measurement was conducted by performing laboratory tests on fabrics,which were sourced from commercial fabric market. Both measurements are evaluated according to the results on those fabric criteria in order to determine the most suitable kind of fabric for the end purpose. As a result of the comparison, it was found that T/C 1 scores the highest index. Therefore, it will be suggested for manufacturing child patients' garment to evaluate the fabric suitability to meet the wearers' requirement through hospital trial. 相似文献
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Changing Arctic Ocean freshwater pathways 总被引:7,自引:0,他引:7
Freshening in the Canada basin of the Arctic Ocean began in the 1990s and continued to at least the end of 2008. By then, the Arctic Ocean might have gained four times as much fresh water as comprised the Great Salinity Anomaly of the 1970s, raising the spectre of slowing global ocean circulation. Freshening has been attributed to increased sea ice melting and contributions from runoff, but a leading explanation has been a strengthening of the Beaufort High--a characteristic peak in sea level atmospheric pressure--which tends to accelerate an anticyclonic (clockwise) wind pattern causing convergence of fresh surface water. Limited observations have made this explanation difficult to verify, and observations of increasing freshwater content under a weakened Beaufort High suggest that other factors must be affecting freshwater content. Here we use observations to show that during a time of record reductions in ice extent from 2005 to 2008, the dominant freshwater content changes were an increase in the Canada basin balanced by a decrease in the Eurasian basin. Observations are drawn from satellite data (sea surface height and ocean-bottom pressure) and in situ data. The freshwater changes were due to a cyclonic (anticlockwise) shift in the ocean pathway of Eurasian runoff forced by strengthening of the west-to-east Northern Hemisphere atmospheric circulation characterized by an increased Arctic Oscillation index. Our results confirm that runoff is an important influence on the Arctic Ocean and establish that the spatial and temporal manifestations of the runoff pathways are modulated by the Arctic Oscillation, rather than the strength of the wind-driven Beaufort Gyre circulation. 相似文献