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1.
Mammalian homologues of the Drosophila trp gene have been invoked as the structural basis for the currents associated with capacitative Ca2+ entry (CCE) in many cell types. Trp homologues are members of a large protein family that may associate as channel subunits providing an explanation for the functional diversity of store-operated channels observed in these cells. However, there is little information as to which of these genes are co-expressed at the cellular level. We have examined the tissue specific expression of five mammalian trp genes and determined which are co-expressed in five different cell lines. The results show tissue- and cell-specific co-expression of multiple trp forms. This implies that the subunit composition of a particular CCE channel may vary depending on the cell type. 相似文献
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The authors reply to the comments by Koppelaar and Tolhuizen (see ibid. vol.46, no.9, p.573, 1998). They state that the optimum choice of the slopes used to perform the encoding process in a projection code always results in maximizing the minimum Hamming distance so that d=2 r 相似文献
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The most recent attempts in raising Tc of cuprate superconductors were successful by synthesizing new Hg-based cuprate materials. We discuss some properties of materials from this series with varying numbers of Cu-O planes per unit cell, including the considerable rise of the critical temperature under the influence of external pressure.In the second part of this contribution, various attempts to directly determine the symmetry of the superconducting order parameter of high-Tc cuprates are mentioned and set into perspective. The experimental approaches are all based on probing the phase of the order parameter in suitably connected closed superconducting loops. The evidence for unconventional order-parameter symmetry in these materials is growing. 相似文献
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B Rau C Below W Haensch W Liebrich C von Schilling PM Schlag 《Canadian Metallurgical Quarterly》1995,380(6):359-364
We performed BAEP study to evaluate acoustic nerve involvement in 102 patients affected by peripheral neuropathies of different etiology, predominantly hereditary and inflammatory acquired neuropathies. Prolonged latency of early waves, indicative of slowing in VIII nerve conduction, was found in a high percentage of cases. Abnormalities were far more frequent (44% vs 14%) and severe in patients with demyelinating rather than axonal neuropathy. Among demyelinating neuropathy, the most severe latency delay was found in Hereditary Motor and Sensory Neuropathy type III. The pattern of acoustic nerve involvement differed slightly between Hereditary Motor and Sensory Neuropathy type I and acquired inflammatory demyelinating polyradiculoneuropathy, perhaps reflecting different pathogenetic mechanisms and different sites of VIII nerve demyelination. 相似文献
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Schilling D.L. Milstein L.B. Pickholtz R.L. Bruno F. Kanterakis E. Kullback M. Erceg V. Biederman W. Fishman D. Salerno D. 《Communications Magazine, IEEE》1991,29(11):86-93
Multipath propagation in a broadband CDMA environment is described. A propagation model for broadband spread-spectrum signals is presented. Experimental results relating to the sharing of the band by fixed service microwave users and mobile personal communications network (PCN) users are discussed. Field tests indicate that PCN systems can provide high-quality communications when sharing the spectrum with fixed-service microwave systems in suburban and urban areas 相似文献
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Consolidation Behavior of Flocculated Alumina Suspensions 总被引:2,自引:0,他引:2
Lennart Bergström Christopher H. Schilling Ilhan A. Aksay 《Journal of the American Ceramic Society》1992,75(12):3305-3314
The consolidation behavior of flocculated alumina suspensions has been analyzed as a function of the interparticle energy. Consolidation was performed by a centrifugal force field or by gravity, and both the time-dependent and equilibrium density profiles were measured by a gamma-ray absorption technique. The interparicle energy at contact was controlled by adsorbing fatty acids of varying molecular weight at the alumina/decalin interface. We found that strongly attractive interactions result in a particle network which resists consolidation and shows compressible behavior over a large stress range. The most weakly flocculated suspension showed an essentially incompressible, homogeneous density profile after consolidation at different centrifugal speeds. We also found a significant variation in the maximum volume fraction, φm , obtained, with φm ∼ 0.54 for the most strongly flocculated suspension to φm ∼ 0.63 for the most weakly flocculated suspension. The compresive yield stresses show a behavior which can be fitted to a modified power law. In this paper, we discuss possible correlations between the fitting parameters and physical properties of the flocculated suspensions. 相似文献