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61.
K Arai S Yamamura T Hanyu HE Takahashi H Umezu H Watanabe T Abo 《Canadian Metallurgical Quarterly》1996,157(11):5170-5177
Murine collagen-induced arthritis (CIA) is known as a T cell-mediated autoimmune disease, although autoantibodies are also suspected to be associated with the onset of the disease. To determine the origin of such T cells in the joints of mice with CIA, their phenotypic properties as well as those of T cells in other immune organs were examined in DBA/1 mice. Since a significant number of mononuclear cells (MNC) was also yielded by the joints of normal DBA/1 mice, the properties of these T cells were examined in parallel. When CIA was induced by an intradermal injection of type II collagen at the base of the tail, the numbers of MNC yielded by the regional lymph nodes and the foot joints were doubled. Interestingly, regardless of the onset of CIA, the joints were always comprised of unique T cell populations, including IL-2(R)alpha- beta+ T cells, gammadelta T cells, CD8alpha+ beta- cells, and CD44+ L-selectin- cells. All these properties coincide with those of extrathymic T cells in liver and intestine. In the case of gammadelta T cells in joints, Vgamma and Vdelta usages were unique and different from those in the other organs. More importantly, Vgamma and Vdelta usages in gammadelta T cells in the joints of normal mice and in those of mice with CIA were essentially the same. Taken together with the expression of recombination-activating gene-1 and -2 mRNAs by MNC in mice with CIA, these findings raise the possibility that the joints have their own resident T cells that are extrathymically generated in situ. 相似文献
62.
Suemasu T. Kohno Y. Saitoh W. Watanabe M. Asada M. 《Electron Devices, IEEE Transactions on》1995,42(12):2203-2210
We report on the theoretical and measured characteristics of triple-barrier metal (CoSi2)-insulator(CaF2) (M-I) resonant tunneling transistors (RTT) grown on an n-Si(111) substrate, and the influence of their parasitic elements on the measured characteristics. First, we analyze theoretical characteristics of an M-I RTT, and then show fabrication process and current-voltage (I-V) characteristics obtained at 77 K, in which several degradations are observed: large resonance voltage, low peak-to-valley (P-V) ratios at negative differential resistance (NDR), and reverse base current. Analysis, taking several parasitic elements (e.g., base resistance, substrate resistance and leakage currents connected to the intrinsic transistor) into account, explains observed characteristics well. Finally, we show the first transistor action with large P-V ratios at 300 K, which is achieved by reducing collector-emitter leakage currents 相似文献
63.
T Okabe N Kumagai H Serizawa N Iwabuchi N Watanabe Y Hamada K Tsuchimoto Y Yamada S Morinaga H Ishii 《Canadian Metallurgical Quarterly》1996,23(3):349-353
This case report describes a case of carcinomatous peritonitis which showed a good response to the combination therapy of 5-FU, leucovorin and cisplatin. A 55-year-old man was admitted with complaints of meteorism due to ascites fluid. Ascitic examination showed a high concentration of CEA and CA19-9, and adenocarcinoma cells. Laboratory and radiological examination did not reveal the origin of the carcinoma, and laparotomy suggested an appendiceal origin. The combination chemotherapy with 5-FU, leucovorin and cisplatin was conducted for a total of 11 courses for 2 years with good QOL until his death. This therapy was suggested to be useful for inoperable carcinomatous peritonitis. 相似文献
64.
65.
T Watanabe L Kelsey A Ageitos C Kuszynski K Ino DG Heimann MT Varney HM Shepard MT Vaillancourt DC Maneval JE Talmadge 《Canadian Metallurgical Quarterly》1998,29(5-6):439-451
Adenovirus infection of CD34+ hematopoietic stem/progenitor cells is dependent on the multiplicity of infection (MOI), time of incubation, the volume in which the co-incubation occurs and the presence or absence of growth factors. Studies revealed that a brief co-incubation (1-8 hours), resulted in low levels of transgene expression, suggesting that adenovirus infection of CD34+ cells occurs slowly, and optimal transduction requires a 24 hour exposure to adenovirus. Infection by Ad/beta-gal or Ad/p53 at a MOI of 500:1 provided a high transduction efficiency but inhibited hematopoietic function. However, treatment at a MOI of 50-100 resulted in efficient transduction (10.7-15.7% positive) without detectable toxicity. Secondary proof of adenovirus transgene expression was demonstrated by detection of mRNA for p53 in Ad/p53 infected stem cells. We conclude that a 24 hour exposure to recombinant adenovirus encoding p53 or beta-gal, at a MOI of 50-100 is optimal for in vitro gene transfer to BM cells and has no significant effect on hematopoietic function. Adenovirus-mediated transduction of BM cells can also be modulated by growth factors (IL-3, GM-CSF and G-CSF) with improved gene delivery and maintenance of hematopoietic function. In summary, adenovirus vectors can be used to transiently transduce stem cells, and conditions have been defined to maximize expression and limit inhibitory effects on CD34+ cells. These data support continued investigation of this vector for local cytokine delivery and purging of stem cell products. 相似文献
66.
S Pegoraro S Fiori S Rudolph-B?hner TX Watanabe L Moroder 《Canadian Metallurgical Quarterly》1998,284(3):779-792
Air re-oxidation of fully reduced human endothelin-1 under optimized conditions yields the natural isomer with parallel disulfide bridges and the non-natural isomer with crossed disulfide bridges at a ratio of 3:1. In view of the recently determined highly reducing redox potential of selenocysteine (-381 mV) in peptides, the half-cystine residues Cys3 and Cys11 of the natural isomer of endothelin-1 were replaced by selenocysteine. Taking advantage of the high stability of the diselenide group toward reducing agents for disulfides a regioselective disulfide bridging of the second cysteine pair allowed for straightforward preparation of the [Sec3,Sec11, Nle7]-endothelin-1. NMR structural analysis showed conformational preferences of this endothelin analog that were identical to those of the natural hormone. Similarly, the bioactivity data confirmed that replacement of cysteine residues with selenocysteine was without detectable effect on receptor recognition and signal transduction. Both findings strongly support that the exchange of sulfur against selenium produces a fully isomorphous molecule as recently observed for similar exchanges at the level of methionine residues in proteins. Moreover, oxidative refolding of the fully reduced [Sec3,Sec11,Nle7]-endothelin-1 fulfilled the expectation that the redox potential of the selenocysteines would dictate quantitative formation of the natural isomer. These results suggest that the selenocysteine approach, besides offering an interesting chemical tool for induction of correct oxidative folding of multiple cysteine-containing peptides, should even allow for the preparation of non-natural isomers and thus for studying conformational preferences of folding intermediates in peptides and proteins. 相似文献
67.
M Miyata E Fukaya T Takagi K Watanabe H Saito M Ito R Yoshioka Y Kazuta Y Yusa A Irisawa Y Sato T Nishimaki H Kumakawa R Kasukawa 《Canadian Metallurgical Quarterly》1998,37(12):1058-1063
Two patients with polymyositis (PM) or dermatomyositis (DM) complicated with massive pleural effusion are reported here. Both patients presented a high-grade fever, pleural effusion prominent on the right, and good response to steroid therapy. In a 50-year-old woman with PM, combined process of pleural inflammation, cardiomyopathy and coexisting hypothyroidism were considered to be responsible for the accumulation of the massive pleural effusion. However, in a 34-year-old man with DM, pleural inflammation associated with interstitial pneumonia or pleural microvasculopathy in DM was considered to be responsible for the accumulation of the massive pleural effusion. 相似文献
68.
BACKGROUND: Sulphidoleukotrienes (slt) are important mediators in allergic diseases that are synthesized after allergen-specific stimulation. OBJECTIVES: The aim of this study is to determine in vitro slt production after allergen-specific (Dermatophagoides pteronyssinus) stimulus of peripheral blood leucocytes and to observe whether histamine release in whole blood with the same allergen correlates with slt production. We also wanted to evaluate whether a correlation exists between the release of slt and histamine and other diagnostic procedures as well as various clinical situations. METHODS: We studied 62 patients sensitive to Dermatophagoides pteronyssinus (Der p), 30 atopic controls and 12 healthy donors. We determined slt production using the CAST-ELISA technique and histamine release using two concentrations of Der p extract (20 and 2 ng/mL). We also carried out quantification of specific and total IgE levels, skin tests and pulmonary function test on each patient. RESULTS: We observed a significantly increased slt release after in vitro stimulation with Der p. There was a significant difference in the slt release between controls and sensitive patients (P < 0.001) and between atopic controls and sensitive patients (P < 0.001). The data are similar to those obtained with histamine release. We noted a positive correlation (P < 0.001) between slt and histamine release (r = 0.71, at 2 ng/mL and r = 0.83 at 20 ng/mL). We also found a positive (P<0.001), although weak (r=0.4 with at 2ng/mL, and r = 0.34 with P = 0.003 at 20 ng/mL) correlation between slt release and specific IgE levels as well as between slt release and skin-test reactivity (r = 0.49 at 2 ng/mL and r = 0.45 at 20 ng/mL; P < 0.001). No significant correlation between slt release and asthma severity was observed, although a trend toward higher slt production in severe and moderate asthma was detected. We found a significant (P<0.001) but weak (r=-0.3) negative correlation between age and slt release. With respect to sex-related differences, we found significant differences (P < 0.05) in slt release between the sexes with a higher slt release in men than in women. CONCLUSION: We conclude that CAST-ELISA for quantification of slt production is a useful in vitro method for diagnosing sensitization to Der p. There also exists a close correlation between slt release and other parameters of allergic sensitization in vitro as well as in vivo. 相似文献
69.
The effects of temperature and grain size on the deformation and fracture behaviour of recrystallized Ni3Al doped with boron were investigated by tensile tests at temperatures up to 973 K as a function of grain sizes from 1.6 to 105m. The yield stress showed a positive temperature dependence to a peak temperature in somewhat different manners depending on the grain size. For coarse-grained specimens, a rapid drop in elongation was observed with increasing temperature. The predominant fracture mode changed with temperature from the transgranular fracture of {1 1 1} cracking to brittle intergranular fracture. This embrittlement at elevated temperatures was considered to occur by a high stress concentration at grain boundaries arising from increased flow stress level and the occurrence of grain boundary sliding (GBS). In contrast, the elongation was not so markedly decreased with temperature for intermediate- and fine-grained specimens which exhibited ductile intergranular fracture and cavitation fracture, respectively, at elevated temperatures, and a slant-type fracture and cup-cone fracture, respectively, at low temperatures. The suppression of serious high-temperature embrittlement for intermediate-grained specimens was explained in terms of the slow propagation of a crack formed by GBS, owing to stress relaxation by dynamic recrystallization (DR) and plastic deformation. In the case of ultra-fine-grained specimens a large elongation was developed at elevated temperatures, which was interpreted as that the further occurrence of DR with increasing volume fraction of grain boundaries reduces the cavitation promoted by GBS, and that the limited sliding length due to extremely small grain diameter raises the stress for cavity formation. 相似文献
70.
Makoto Ishiguro Katsufumi Ohmuro Yukito Saitoh Yuuta Takahashi Jun Watanabe Tsutomu Arai Yoji Ito Keiji Mihayashi 《Journal of the Society for Information Display》2012,20(11):598-603
We have successfully developed a quarter‐wave retardation film (QWF) for wide viewing angle 3D liquid crystal displays (3D‐LCDs) that provides high luminance, low crosstalk, low color change, and low head‐tilt‐angle dependency. It was found that the out‐of‐plane retardation (Rth) of the QWF in the LCD needs to be close to 0 nm in order to improve the 3D display properties at an off‐axis position and that the in‐plane retardation (Re) needs to be adjusted from 120 to 130 nm to achieve low color change with head tilting. We adopted a coating process for making our QWF because of its potential for retardation control. 3D‐LCDs with this QWF whose Rth was nearly zero had high performance and allowed off‐axis other than on‐axis. 相似文献