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排序方式: 共有1018条查询结果,搜索用时 15 毫秒
91.
92.
Tomiji Wakida Huishun Li Yukihiro Sato Haruo Kawamura Mitsuo Ueda Haruo Mizushima Shoji Takekoshi 《Coloration Technology》1993,109(9):292-296
Polyester fabrics and films treated with two fluorocarbon resins were washed and heat treated. Water repellency, surface tension and ESCA measurements were carried out. Changes in the water repellency of the resin-treated polyester fabric caused by washing and heat treatment are related to modification of the chemical composition of the polyester surface. 相似文献
93.
We propose, here, new theory of high Tc superconductivity mechanism. The hole-Cooper pair formation and the Bose condensation of the Cooper pairs occur in the high Tc superconducting oxides such as Bi?Sr?Ca?Cu?O. The atractive interaction is due to the antiferromagnetic order and its fluctuation of CuO2 plane. Dependence of Tc on the numbers of CuO2 layers is quantitatively analized. 相似文献
94.
The pharmacological profile and the acute and chronic aquaretic effects of OPC-41061, a novel nonpeptide human arginine vasopressin (AVP) V2-receptor antagonist, were respectively characterized in HeLa cells expressing cloned human AVP receptors and in conscious male rats. OPC-41061 antagonized [3H]-AVP binding to human V2-receptors (Ki = 0.43 +/- 0.06 nM) more potently than AVP (Ki = 0. 78 +/- 0.08 nM) or OPC-31260 (Ki = 9.42 +/- 0.90 nM). OPC-41061 also inhibited [3H]-AVP binding to human V1a-receptors (Ki = 12.3 +/- 0.8 nM) but not to human V1b-receptors, indicating that OPC-41061 was 29 times more selective for V2-receptors than for V1a-receptors. OPC-41061 inhibited cAMP production induced by AVP with no intrinsic agonist activity. In rats, OPC-41061 inhibited [3H]-AVP binding to V1a-receptors (Ki = 325 +/- 41 nM) and V2-receptors (Ki = 1.33 +/- 0. 30 nM), showing higher receptor selectivity (V1a/V2 = 244) than with human receptors. A single oral administration of OPC-41061 in rats clearly produced dose-dependent aquaresis. In treatment by multiple OPC-41061 dosing for 28 days at 1 and 10 mg/kg p.o. in rats, significant aquaretic effects were seen throughout the study period. As the result of aquaresis, hemoconcentration was seen at 4 hr postdosing although, no differences were seen in serum osmolality, sodium, creatinine and urea nitrogen concentrations at 24 hr postdosing. Furthermore, there was no difference in serum AVP concentration, pituitary AVP content or the number and affinity of AVP receptors in the kidney and liver at trough throughout the study period. These results demonstrate that OPC-41061 is a highly potent human AVP V2-receptor antagonist and produces clear aquaresis after single and multiple dosing, suggesting the usefulness in the treatment of various water retaining states. 相似文献
95.
I Kawamura J Yang Y Takaesu M Fujita K Nomoto M Mitsuyama 《Canadian Metallurgical Quarterly》1994,62(10):4396-4403
It has been shown that gamma interferon (IFN-gamma)-producing CD4+ T cells, which are generated only by immunization with viable bacteria, exert a significant role in protective immunity against mycobacteria in mice. In this study, we have tried to determine the antigen recognized by the T cells in search of a possible protective antigen. T cells from viable Mycobacterium bovis BCG-immunized mice were stimulated with several antigens, and IFN-gamma production was measured. Purified protein derivative and viable and killed BCG lysates caused significant IFN-gamma production, and almost the same level of IFN-gamma activity was detected in both groups stimulated with viable and killed BCG lysates. However, heat shock protein (HSP) 65 and HSP 70 were not a major antigen for IFN-gamma production. The antigen provoking IFN-gamma production is localized mainly in the membrane fraction of BCG cells, and the approximate molecular size was 18 kDa. On the other hand, T cells from killed BCG-immunized mice never responded to this antigen for IFN-gamma production, whereas they could mount a delayed-type hypersensitivity response. These results showed that the antigen provoking IFN-gamma production was present in killed as well as viable BCG. In addition to the antigen presentation by antigen-presenting cells, some kinds of differentiation factor (such as monokines) that are produced only by stimulation with viable cells seemed to be necessary for the development of IFN-gamma-producing T cells. 相似文献
96.
M. Inokuchi D. Kawamura Y. Sakka K. Yabuuchi K. Yakushi I. Shirotani J. Hayashi H. Kawamura H. Inokuchi 《Journal of Low Temperature Physics》2006,142(3-4):213-217
We have studied the effect of shear stress on thin films of Pt(dpg)2 and chromic compounds, spiropyrans, by using the sapphire-anvil cell. From Raman spectra under hydrostatic pressure and shear
deformation, the shear stress effect on Pt(dpg)2 was quantitatively estimated. Then, it was observed that the color of spiropyran (1′,3′-dihydro- 1′,3′,3′-trimethyl-6-nitro-spiro
[2H-1-benzopyran-2,2′-[2H]indole]) was changed by shear stress. 相似文献
97.
A Higuchi H Nakai M Miyazato M Izumitani S Shishido T Kawamura 《Canadian Metallurgical Quarterly》1996,87(10):1145-1150
BACKGROUND: It is difficult to diagnose intermittent hydronephrosis and to decide the indication of surgical intervention. We investigated 23 cases of intermittent hydronephrosis. METHODS: From 1978 to 1995, a total of 23 patients were diagnosed as intermittent hydronephrosis in our institution. We inspected their clinical features and treatment which had been performed to them. RESULTS: Our study comprised 21 boys and 2 girls, whose mean age was 6 year old. Their chief complaint was intermittent flank pain (left: 21, right: 1, bilateral: 1) accompanied with gross hematuria (30%) and vomiting (39%). When they were asymptomatic, an excretory urogram revealed only mild pelvic dilatation without calyceal distension and kinking of ureteropelvic junction. Split renal function study by RI showed no difference between the affected side and the normal side except one case. When pelvic or calyceal enlargement was confirmed on ultrasonography while they were symptomatic, surgery was indicated. Surgery was performed in 17 cases (74%) including dismembered pyeloplasty in 14 cases, resection of aberrant vessel in 1, relocation of lower pole renal vessel in 1 and nephrectomy in 1. In surgical and histological view points, intrinsic stenosis was seen in 10 cases, extrinsic obstruction caused by aberrant vessels was seen in 4 and ureteral polyp was seen in 3 (bilateral polyp in 1 case). CONCLUSION: They had no more symptoms after operation. Of 23 among followed up cases without surgery, we experienced 2 cases unexpectedly advancing irreversible hydronephrotic change after the last attack, 1 case of gradually progressing hydronephrotic change and 1 case of severe renal dysfunction after many attacks. Therefore intermittent hydronephrosis should be followed up carefully. 相似文献
98.
S Matsumoto Y Kang S Sato Y Kawakami Y Oda M Araki J Kawamura H Uchida 《Canadian Metallurgical Quarterly》1998,88(5):890-894
1. We recently demonstrated that intrathecal administration of prostaglandin E2 (PGE2) and PGF2alpha induced allodynia through a pathway that includes the glutamate receptor and nitric oxide (NO)-generating systems from pharmacological studies. In order to clarify the involvement of NO in prostaglandin-induced allodynia, we measured NO released from rat spinal cord slices by a chemiluminescence method. 2. PGE2 stimulated NO release from both dorsal and ventral regions all along the spinal cord. PGE2 stimulated the release within 10 min and increased it in a time-dependent manner. 3. The PGE2-induced NO release was observed at 100 nM-10 microM. PGF2alpha stimulated the release at concentrations higher than 1 microM, but PGD2 (up to 10 microM) did not enhance it. 4. 17-Phenyl-omega-trinor PGE2 (EP1 > EP3) and sulprostone (EP1 < EP3) were as potent as PGE2, but PGE1 was less potent, in stimulating NO release. While M&B 28767 (EP3) did not enhance the release, butaprost (EP2) stimulated it at 1 microM. The PGE2-evoked release was blocked by ONO-NT-012, a bifunctional EP1 antagonist/EP3 agonist. 5. The PGE2-evoked release was Ca2+-dependent and blocked by MK-801 (NMDA receptor antagonist) and L-NAME (NO synthase inhibitor). The release was also inhibited by PGD2 and dibutyryl-cyclic AMP. 6. The present study demonstrated that PGE2 stimulates NO release in the rat spinal cord by activation of NMDA receptors through the EP1 receptor, and supports our previous findings that the NO-generating system is involved in the PGE2-induced allodynia. 相似文献
99.
Y Akasaka Y Ishikawa S Kato T Ishii T Masuda K Fujita T Yamada S Kawamura 《Canadian Metallurgical Quarterly》1998,11(11):1107-1114
To examine the role of the Fas ligand/Fas (FasL/Fas) system and apoptosis in renal allograft rejection, we analyzed FasL/Fas expression and apoptosis in 63 renal allograft biopsy specimens obtained from 56 renal transplant recipients in Tokyo, Japan. Sixteen biopsy specimens were diagnosed (Banff criteria) as acute rejection (AR), 17 as AR plus chronic rejection, 10 as borderline stages, and 20 as no rejection (NR). Immunohistochemically, Fas antigen was highly expressed in the renal tubular epithelium in tissues from patients with rejection. The mean number of Fas-positive tubular epithelium was significantly higher in biopsy specimens with AR than in those with NR, but FasL expression was highly expressed in infiltrating lymphocytes in the interstitium of allografts with cellular rejection. The mean number of FasL-positive infiltrating lymphocytes was significantly higher in specimens with AR than in those with NR or borderline stages. For detection of apoptotic cells, the specimens were subjected to terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end-labeling, which showed that the mean number of tubular epithelial cells positive for this labeling was highest for the specimens with AR, the number being significantly higher than in those with AR plus chronic rejection or with NR. Thus, Fas expression on epithelial cells might actively trigger their apoptosis by the interaction between Fas and FasL. Studies of human normal renal-derived cell lines (RPTEC 2601 [epithelial] and NHMC 5155 [mesangial]) showed that both constitutively expressed Fas (but not FasL) mRNA. After pretreatment with interferon-gamma, Fas-induced apoptosis was observed in the RPTEC 2601 line, but without interferon-gamma pretreatment, anti-Fas-mediated apoptosis was not seen. Under identical conditions, the NHMC 5155 line was resistant to anti-Fas-mediated apoptosis regardless of interferon-gamma pretreatment. This suggested that AR might be associated with increased apoptosis in the renal tubular epithelial cells mediated by the Fas/FasL system. 相似文献
100.