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11.
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Seshita T. Ikeda Y. Wakimoto H. Ishida K. Terada T. Matsunaga T. Suzuki T. Kitaura Y. Uchitomi N. 《Solid-State Circuits, IEEE Journal of》1994,29(12):1583-1588
An ultrahigh-speed 8 bit multiplexer (MUX) has been developed for future-generation optical-fiber communication systems having a data rate of 20 Gb/s. This IC was fabricated using a 0.5 μm WNx/W-gate GaAs MESFET process based on optical lithography, ion implantation, and furnace annealing for good reproducibility and high throughput. The WNx/W bilayer gate has a low sheet resistance, improving the circuit high frequency performance. To attain 20 GHz operation, advanced circuit techniques for the source-coupled FET logic (SCFL) were introduced. A cross coupled source-follower (CCSF) was developed mainly for the highest speed buffers to enhance the bandwidth. The first-stage T-type flip-flop was designed with optimization techniques and operated up to 21.1 GHz 相似文献
13.
F Bigoni U Koehler R Stanyon T Ishida J Wienberg 《Canadian Metallurgical Quarterly》1997,102(3):315-327
The adhesive core of the desmosome is composed of cadherin-like glycoproteins of 2 families, desmocollins and desmogleins. The desmosomal cadherins show distinct patterns of expression in adult epidermis, and we have suggested that the desmocollins have a functional role in regulating the differentiation and/or morphogenesis of that epithelium (North et al. [1996] Proc. Natl. Acad. Sci. USA 93:7701-7705.). To examine this hypothesis, we cloned murine desmocollins and examined the induction patterns of desmocollins 1 and 3 during skin and skin appendage development. Desmocollins 3 and 1 were first expressed in epidermis in highly regional patterns at embryonic days 13.0 and 13.5, respectively, and both were up-regulated in general body epidermis at day 14.5. At this stage, epidermis is undifferentiated and the desmocollins showed an unexpected expression pattern. However, by day 18.5 when skin had undergone terminal differentiation, desmocollin 1 and 3 expression resembled that found in the adult. Thus, the establishment of the adult pattern of desmocollin expression corresponds to the adult pattern of epidermal stratification. We suggest that it is the ratio of desmocollin 1 to desmocollin 3 expression at different levels in the epidermis that is fundamental in establishing this pattern of differentiation. 相似文献
14.
J Kido C Kasahara K Ohishi S Nishikawa H Ishida K Yamashita S Kitamura K Kohri T Nagata 《Canadian Metallurgical Quarterly》1995,40(10):967-972
Osteopontin is a prominent non-collagenous component of bone matrix, although it is expressed in several other tissues. Recently, osteopontin was reported to be involved in urinary stone formation and atherosclerotic lesions of the aorta, suggesting that it may be a key protein associated with these types of pathological mineralization. In this study, whether or not human dental calculus contains osteopontin was investigated by immunoblotting and immunohistochemical analyses. After extraction of calculus proteins with EDTA and separation of the proteins by electrophoresis, immunoblotting analysis revealed the presence of osteopontin. Two forms of osteopontin appeared at 61 and 68 kDa on 10% polyacrylamide gel and the proteins were digested with thrombin, a highly specific protease. Moreover, immunohistochemical analysis revealed that osteopontin was localized in dental calculus adherent to tooth roots. These findings indicate that osteopontin is, in fact, present in human dental calculus and may be involved in calculus formation as the stone matrix. 相似文献
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K Iguchi M Hamatake R Ishida Y Usami T Adachi H Yamamoto K Koshida T Uchibayashi K Hirano 《Canadian Metallurgical Quarterly》1998,253(3):766-770
Endothelin-1 (ET-1) is a cardiovascular peptide that binds to two distinct receptors, ET(A) and ET(B), resulting in systemic and regional vasoconstriction, alteration in sodium excretion, mitogenesis, and release of other vasoactive peptides such as atrial natriuretic peptide (ANP). A role for ET-1 has been proposed in congestive heart failure (CHF) based on the increase in circulating ET-1 in this cardiovascular disease state. The present study determined the cardiorenal and endocrine responses to chronic selective oral ETA antagonism in experimental CHF. Two groups of conscious dogs underwent 21 days of pacing-induced CHF. These groups included a control untreated group (n = 6) and a group that received an orally active ET(A) receptor antagonist (A-127722, Abbott Pharmaceuticals, 5 mg/kg PO bid, n = 6). Each group was studied at baseline before the onset of CHF and after 14 and 21 days of CHF. Compared with the CHF control group, the ET(A) receptor antagonism group at 14 days of CHF showed lower mean arterial pressure and systemic vascular resistance. Similarly, ET(A) receptor antagonism markedly attenuated the increase in circulating ANP despite similar atrial pressures. At 21 days of CHF, ET(A) receptor antagonism lowered pulmonary artery pressure, pulmonary vascular resistance, and systemic vascular resistance in association with a higher cardiac output. Plasma ANP remained suppressed. Despite the lower mean arterial pressure and circulating ANP in the ET(A) receptor antagonist group, the absolute decrease in sodium excretion from baseline was less compared with the untreated CHF control group. The present investigation supports the conclusion that endogenous ET-1 participates in the systemic and pulmonary vasoconstriction, the elevation of ANP, and the sodium retention that characterize this model of experimental CHF, suggesting a potential therapeutic role for ET(A) receptor antagonism in CHF. 相似文献
17.
A Hamasaki F Sendo K Nakayama N Ishida I Negishi K Nakayama S Hatakeyama 《Canadian Metallurgical Quarterly》1998,188(11):1985-1992
To elucidate the role of A1, a new member of the Bcl-2 family of apoptosis regulators active in hematopoietic cell apoptosis, we established mice lacking A1-a, a subtype of the A1 gene in mice (A1-a-/- mice). Spontaneous apoptosis of peripheral blood neutrophils of A1-a-/- mice was enhanced compared with that of either wild-type mice or heterozygous mutants (A1-a+/- mice). Neutrophil apoptosis inhibition induced by lipopolysaccharide treatment in vitro or transendothelial migration in vivo observed in wild-type mice was abolished in both A1-a-/- and A1-a+/- animals. On the other hand, the extent of tumor necrosis factor alpha-induced acceleration of neutrophil apoptosis did not differ among A1-a-/-, A1-a+/-, and wild-type mice. The descending order of A1 mRNA expression was wild-type, A1-a+/-, and A1-a-/-. Taken together, these results suggest that A1 is involved in inhibition of certain types of neutrophil apoptosis. 相似文献
18.
A Houjin is an n by n square lattice with each cell containing a symbol (such as a number or a letter). Further, these numbers or letters are designed
to exhibit symmetry. For example, a magic square is a Houjin where the embedded symmetry is that the numbers in each row,
column, and a center diagonal have an equal sum. This article reports a new Houjin: a dynamic Houjin. A dynamic Houjin changes
its numbers at each time step while satisfying the symmetry as a Houjin (a magic square). The dynamic Houjin has a further
symmetry in a time dimension, i.e., the sums of the numbers in each cell are identical. 相似文献
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20.
The effect of potential catalysts on the curing reaction of a new type of phenolic resins obtained from benzoxazine precursors is studied. These novel resins solve the shortcomings of traditional phenolics because they cure by a ring-opening mechanism that avoids the release of volatiles. Isothermal and nonisothermal differential scanning calorimetry (DSC) data is used to determine the influence of the catalysts on the curing kinetics. Fourier transform infrared (FTIR) spectroscopy is also applied. The benzoxazine chosen for this study is a purified benzoxazine monomer based on bisphenol-A, formaldehyde, and aniline. The as-synthesized benzoxazine precursor is also studied to determine the influence of the dimers and higher oligomers in the curing mechanism. The presence of these structures seems to catalyze the curing reactions. The activation energy and overall reaction order of the as-synthesized precursor are determined. Among the catalysts tested, adipic acid shows the most promising results. For all the cases studied the curing reaction is autocatalyzed up to a diffusion-controlled stage. © 1995 John Wiley & Sons, Inc. 相似文献