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91.
S. Nakao K. Ueno T. Hanaguri K. Kitazawa T. Fujita Y. Nakayama T. Motohashi J. Shimoyama K. Kishio T. Hasegawa 《Journal of Low Temperature Physics》1999,117(3-4):341-345
We have performed scanning tunneling microscopy/spectroscopy (STM/STS) on single crystals of heavily Pb-doped Bi
2
Sr
2
CaCu
2
O
y
(Pb-Bi2212). The obtained STM images clearly demonstrated phase separation into the and phases with lamella-type and new zigzag-like microstructures. From the site-specified tunneling measurements, it was directly confirmed that the phase possesses higher T
c
. This suggests that the phase boundaries act as strong pinning sites especially at higher temperatures. 相似文献
92.
H Ohminami M Yasukawa S Kaneko Y Yakushijin Y Abe Y Kasahara Y Ishida S Fujita 《Canadian Metallurgical Quarterly》1999,93(3):925-935
The mechanism underlying the cytotoxicity mediated by a human CD4(+) cytotoxic T-lymphocyte (CTL) clone directed against a peptide derived from the acute myelogenous leukemia-associated fusion protein, DEK-CAN, was investigated. A DEK-CAN fusion peptide-specific CD4(+) Th0 CTL clone, designated HO-1, was established from the peripheral blood lymphocytes of a healthy individual. HO-1 exerted direct but not "innocent bystander" cytotoxicity within 2 hours. The cytotoxicity mediated by HO-1 was completely Ca2+-dependent. Because HO-1 lysed peptide-loaded Fas-deficient target cells derived from a patient with a homozygous Fas gene mutation, its cytotoxicity appeared to be mediated by a Fas-independent pathway. In addition, its cytotoxicity was only partially inhibited by treatment with concanamycin A and strontium ions, which are inhibitors of the perforin-based cytotoxic pathway. Although membrane-bound type of tumor necrosis factor-alpha (TNF-alpha) was expressed on HO-1, an anti-TNF-alpha antibody had no effect on HO-1-mediated cytotoxicity. HO-1 expressed mRNA for apoptosis-inducing mediators, including perforin, granzyme B, Fas ligand, TNF-alpha, and lymphotoxin; however, no DNA fragmentation was detected in target cells incubated with HO-1 by 5-[125I]Iodo-2'-deoxyuridine release assay and agarose gel electrophoresis of DNA. Although it has been suggested that the Fas/Fas ligand system is the main pathway by which CD4(+) CTL-mediated cytotoxicity is exerted in murine systems, HO-1 produced peptide-specific and HLA-restricted cytotoxicity via a Fas-independent and nonapoptotic pathway. The present study thus describes a novel mechanism of cytotoxicity mediated by CD4(+) CTL. 相似文献
93.
T Okamura S Yokoyama E Kou N Inoue T Kuriyama A Matsumuro H Fujita T Tanaka K Miyao 《Canadian Metallurgical Quarterly》1998,51(10):845-848
A 57-year-old man was admitted to our hospital because of restenosis of the left main coronary trunk (LMT) after patch angioplasty for the LMT lesion. PTCA was repeated four times during three years after patch angioplasty, but recent coronary angiogram still demonstrated 75% restenosis of the LMT lesion. Double-CABG was performed to LAD and LCX using the left internal thoracic artery and saphenous vein graft. Postoperative coronary angiogram revealed an excellent result. A careful consideration must be given to the indication of the patch angioplasty of the LMT lesion. 相似文献
94.
Fujita M. Namerikawa T. Matsumura F. Uchida K. 《Automatic Control, IEEE Transactions on》1995,40(3):530-536
This paper deals with μ-synthesis of an electromagnetic suspension system. First, an issue of modeling a real physical electromagnetic suspension system is discussed. We derive a nominal model as well as a set of models in which the real system is assumed to reside. Different model structures and possible model parameter values are fully employed to determine unstructured additive plant perturbations, which directly yield uncertainty frequency weighting function. Second, based on the set of plant models, we setup robust performance control objectives. Third, we make use of the D-K iteration approach for the controller design. Finally, implementing the controller with a digital signal processor, experiments are carried out. With these experimental results, we show robust performance of the designed control system 相似文献
95.
OBJECTIVE: Our purpose was to determine whether the secretory component of immunoglobulin A in maternal serum predicts delivery before 34 weeks' gestation. STUDY DESIGN: Primigravid women of an urban population in New Zealand were recruited at booking into a prospective longitudinal nested case control study (n = 1651; after exclusions and withdrawals, n = 1511). Serum was collected at 8 to 12 weeks, 15 to 18 weeks, 21 to 24 weeks, 28 to 30 weeks, and 36 to 38 weeks of gestation and 6 weeks post partum. Concentrations of the secretory component of immunoglobulin A were determined by enzyme-linked immunosorbent assay in all women who were delivered preterm (n = 53) and in controls randomly selected from women delivered at > or =37 weeks' gestation (n = 178). RESULTS: Serum concentrations of the secretory component of immunoglobulin A were similar in women delivered at term or preterm throughout pregnancy (n = 21 delivered at <34 weeks and n = 32 at 34 to 36.9 weeks, incidence 3.5%). Receiver-operator characteristic curves showed no discriminating ability of the secretory component of immunoglobulin A. Smokers had 50% higher concentrations than nonsmokers did (p < 0.0001 by analysis of variance). CONCLUSION: The secretory component of immunoglobulin A in maternal serum does not predict preterm delivery in a low-risk population. 相似文献
96.
T Takubo N Tatsumi I Tsuda K Kasuya Y Taniguchi T Fujita K Uchida Y Matsuo T Hayashi 《Canadian Metallurgical Quarterly》1998,99(4):234-235
Cytomegalovirus (CMV) gastritis has been reported in transplant patients. Symptoms are considered nonspecific, and gastroscopy with biopsy is usually performed to establish the diagnosis. Three patients are described here 1 to 3 months after solid organ transplantation, with primary CMV gastritis, confirmed by gastroscopy, histopathologic examination and cultures. The clinical presentation in all three cases was sharp epigastric pain that decreased in a supine position, increased while sitting and further increased when standing or walking. The epigastric pain completely resolved after treatment with ganciclovir. To the best of our knowledge, such postural epigastric pain has not been described as a specific symptom in any other clinical entity and may be a unique sign of primary CMV gastritis. 相似文献
97.
M Nishi H Miyake J Hanai K Fujita Y Hatae T Takeda 《Canadian Metallurgical Quarterly》1998,5(6):1399-1402
There have been a number of contradictory views concerning the efficacy of mass screening for neuroblastoma. Three Japanese and one cohort study from Quebec, and three Japanese cross-sectional studies were reviewed. The four cohort studies revealed that mass screening using high performance liquid chromatography (HPLC) reduced the incidence of this disease by about half in children aged from 1 to 4 years while little reduction was noted in screening utilizing non-HPLC methods. There is a large difference in the efficacy of mass screening depending on the method used. In the three cross-sectional studies, there was no discrimination between screened and unscreened cases, or between subjects screened by HPLC and non-HPLC methods. The percentage of children in the cross-sectional studies screened by HPLC was low. Cross-sectional studies seem inappropriate in assessing the effectiveness of current HPLC mass screening. 相似文献
98.
M Hisada T Fujita H Naoki Y Itagaki H Irie M Miyashita T Nakajima 《Canadian Metallurgical Quarterly》1998,36(8):1115-1125
Facile structure determination of acylpolyamines, glutamatergic nerve blocker obtained from the venom of the Joro spider (Nephila clavata) was carried out with the use of micro-column LC/MS and high energy collision induced dissociation (CID) mass spectrometry. 6-hydroxyindole-3-acetyl was proposed previously as a putative partial structure, for the acyl moiety of hydroxyindole-type polyamines (NPTX-1 to -6). The NMR data obtained for NPTX-6, NPTX-687 and hydroxyindole-3-acetic acid which was released by acid hydrolysis of Nephila clavata crude venom extracts proved that the lipophilic head is the 4-hydroxyindole-3-acetic acid. Various hydroxyindole-3-acetyl polyamines were found in N. Clavata venom and characterized by mass spectrometry. As a result, type-E, a new class of generalized acylpolyamine structure was proposed in addition to the previously reported polyamine backbones type-A to -D. 相似文献
99.
Y Nagai T Azuma M Funauchi M Fujita M Umi M Hirano T Matsubara S Ueno 《Canadian Metallurgical Quarterly》1998,157(1):52-59
This study examined the effect of thyrotrophin-releasing hormone (TRH) administration on thermoregulation in the newborn. Twin lambs were either delivered near-term by caesarean section or born vaginally at term. Colonic temperature, O2 consumption, CO2 production, breathing and heart rates, plus plasma thyroid hormone and nonesterified fatty acid (NEFA) concentrations and thermogenic activity (i.e. GDP binding) of brown adipose tissue (BAT) were measured. In caesarean section delivered lambs colonic temperature decreased rapidly after birth, a response that was greater in the group designated for TRH treatment, in which colonic temperature fell to below 36.0 degrees C at 80 min of life, prior to TRH administration. At this age colonic temperature had been restored to a mean of 38.70 degrees C in controls. TRH had no influence on the composition or thermogenic activity of BAT. The incidence of shivering was not influenced by TRH, but treated lambs maintained a higher rate of O2 consumption and ventilation compared with controls after colonic temperature had been restored to 38.56 degrees C. TRH appeared to promote fat oxidation as O2 consumption remained unchanged and CO2 production declined by a greater rate in treated lambs, resulting in a lower respiratory quotient compared to controls. Heart rate and plasma concentrations of NEFA increased following TRH administration although this did not result in values greater than controls. Normothermic lambs born vaginally had BAT with a greater thermogenic activity, higher plasma thyroid hormone and NEFA concentrations compared with caesarean section delivered lambs, but a thermogenic response was not observed to TRH despite a rise in thyroid hormone concentrations. In conclusion, TRH can improve thermoregulation, an effect that could be linked to an increase in fat oxidation. 相似文献
100.