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排序方式: 共有866条查询结果,搜索用时 15 毫秒
31.
32.
K Osuka Y Suzuki T Tanazawa K Hattori N Yamamoto M Takayasu M Shibuya J Yoshida 《Canadian Metallurgical Quarterly》1998,140(9):943-951
The authors characterized the role of interleukins in the cerebrospinal fluid (CSF) in the development of vasospasm after subarachnoid haemorrhage (SAH), particularly interleukin-6 (IL-6). Concentrations of interleukin-1 beta (IL-1 beta), IL-6, and interleukin-8 (IL-8) were measured serially in CSF of 24 patients and in serum of 9 patients with SAH and correlated clinically. Additionally, the effects of the same cytokines on the cerebral arteries of dogs were analyzed on angiograms after intracisternal injection. Changes in levels of eicosanoids, angiogenic factors, and soluble cell adhesion molecules were investigated in the CSF of injected dogs. CSF concentrations of IL-6 and IL-8 were elevated significantly above control levels from the acute stage of SAH until the chronic stage. Patients with symptomatic vasospasm had significantly higher levels of IL-6 as well as IL-8 in CSF on days 5 and 7. Intracisternal injection of IL-6 induced long-lasting vasoconstriction in five out of eight dogs, while IL-8 did not. The diameter of canine basilar artery after IL-6 was reduced 29 +/- 5% from pretreatment diameter at 8 hours. Prostaglandins E2 and I2 were elevated in CSF for the first 4.5 hour of this IL-6-induced vasospasm. Neither angiogenic factors such as platelet-derived growth factor-AB and vascular endothelial growth factor nor soluble cell adhesion molecules were significantly elevated in CSF. IL-6, which increases to very high concentrations in CSF after SAH, may be important in inducing vasospasm, as IL-6 produced long-lasting vasoconstriction in the canine cerebral artery, which may be partly related to activation of the prostaglandin cascade. 相似文献
33.
34.
Y Nakagawa-Hattori T Hattori T Kondo Y Mizuno 《Canadian Metallurgical Quarterly》1995,45(12):2279-2281
We report thiolmethyltransferase (TMT) activity in RBC membrane preparations from patients with Parkinson's disease (PD), normal controls, and patients with symptomatic parkinsonism. Unlike previous reports, our report found no significant decrease in TMT activity in PD patients compared with normal controls. Low S-methylation capacity does not appear to be a risk factor for PD in Japanese patients. 相似文献
35.
K Kimura S Hattori Y Kabuyama Y Shizawa J Takayanagi S Nakamura S Toki Y Matsuda K Onodera Y Fukui 《Canadian Metallurgical Quarterly》1994,269(29):18961-18967
The effects of wortmannin (WT), an inhibitor of phosphatidylinositol (PI) 3-kinase, on differentiation of PC12 cells were analyzed. WT inhibited PI 3-kinase activity of PC12 cells at a concentration of 10(-7) M in vivo and in vitro. Transient inhibition of PI 3-kinase activity at the time of nerve growth factor stimulation had no effect on activation of the ras protein or neurite formation by the cells. However, continuous inhibition of PI 3-kinase blocked differentiation at the step just before neurite formation. When WT was applied to cells growing neurites, elongation of the neurites was stopped at that step. These results suggest that PI 3-kinase may be involved in neurite elongation. 相似文献
36.
BACKGROUND: An important unanswered question concerning the histogenesis of superficial-type gastric carcinoma is whether it is monoclonal or multiclonal in origin. Therefore, the authors analyzed multiple areas of each cancer with a clonality assay based on trinucleotide repeat length polymorphism of the human androgen receptor gene (HUMARA) that was subject to random inactivation of X chromosomes. METHODS: The HUMARA assay was applied to 15 gastric carcinomas, early and advanced stage, manifested in superficial, depressed lesions of various sizes and at least some signet ring cells. DNA was extracted from fresh frozen and formalin fixed tumor tissues that were microdissected from the mucosal lesions, and the HUMARA locus was amplified by polymerase chain reaction with and without prior digestion of nonmethylated DNA with Hpa II. The amplified DNA samples were loaded on polyacrylamide gels, electrophoresed, and visualized by a silver-staining method. RESULTS: In the 15 cases examined, 9 cancers were informative (had features of the types sought in this study), and in these 9 cancers a total of 57 areas were analyzed. In 7 of the 9 cancers, the inactivated allele was common to all the informative areas of each tumor, irrespective of the macroscopic shape of the tumor or the degree of histologic heterogeneity within it. In one of the two remaining cancers, the inactivated allele of one of the areas examined was different from those in the other areas. CONCLUSIONS: Most of the superficial depressed-type gastric carcinomas in this study were demonstrated to be of monoclonal origin. This finding supports a notion expressed previously in the literature that superficial-type carcinoma has a long natural history, and it indicates that efforts to detect gastric carcinomas in early stages to improve patients' survival should be encouraged. 相似文献
37.
Takeo Hattori Atsushi Shigemori Jun-Ichi Mohri Masahiro Yoshimura Shigeyuki Somiya 《Journal of the American Ceramic Society》1982,65(9):c142-c142
Powder compacts of synthetic mica (fluorphlogopite) encapsulated in a boro–silicate glass tube were isostatically hot–pressed in a Roy–Tuttle–type pressure vessel. Synthetic mica was sintered to a density of 2.60 g/cm3 (91.2% of theoretical density) without additives under 98 MPa of water at 800°C for 45 min. 相似文献
38.
Shinnosuke Miyauchi Yasuo Hattori Toshiyuki Takamatsu Yoshio Sorimachi 《应用聚合物科学杂志》1992,44(3):377-381
A method to generate a porous region near the surface of a polymer is suggested. In this method the region near the surface is swollen by immersing the polymer for a short time in a solvent. Subsequently, the polymer is introduced in a nonsolvent (for the polymer) that is, however, miscible with the solvent. The formation of the porous region is a result of (1) the swelling accompanied by the disentanglement of the surface molecular chains, and the dissolution of some of them during the immersion in the solvent, and (2) the rapid extraction of the solvent from the swollen region by the nonsolvent. The porous surface provides a matrix into which a second incompatible monomer can be polymerized so that the two otherwise incompatible polymers can adhere to one another. 相似文献
39.
Effects of support and additive on oxidation state and activity of Pt catalyst in propane combustion 总被引:1,自引:0,他引:1
The effects of support and additive on the oxidation state and catalytic activity of Pt catalyst in the low temperature propane combustion were systematically investigated on Pt/MgO, Pt/Al2O3 and Pt/SiO2–Al2O3. The catalytic activity varied much with both support materials and additives. The catalyst on the more acidic support showed higher activity, and the catalytic activity on every support materials increased as the electronegativity of additives increased, while some additives decreased the activity. The oxidation state of platinum, estimated by white line intensity of Pt LIII-edge XANES spectrum, also varied with the support and additives, and additives with higher electronegativity greatly prevented the platinum from its oxidation under oxidising atmosphere. Among almost all the catalysts with various supports and various additives, a clear relationship was observed between the oxidation state of platinum and the catalytic activity; the more metallic platinum showed higher activity. Thus, it was concluded that the total electrophilic/electrophobic property derived from those of the support and additive controls the oxidation state of platinum, which intensively affects the catalytic activity; i.e. higher electrophilic property provides less oxidised platinum, resulting in high catalytic activity. The mechanism of this effect was also discussed on the basis of thermochemical data, and it was proposed that the electrophobic materials promote the noble metal oxidation since the noble metal oxo-anion such as PtOδ− is more stabilised with electrophobic cation. 相似文献
40.
Ryuta Shigefuku Hideaki Takahashi Hiroyasu Nakano Tsunamasa Watanabe Kotaro Matsunaga Nobuyuki Matsumoto Masaki Kato Ryo Morita Yousuke Michikawa Tomohiro Tamura Tetsuya Hiraishi Nobuhiro Hattori Yohei Noguchi Kazunari Nakahara Hiroki Ikeda Toshiya Ishii Chiaki Okuse Shigeru Sase Fumio Itoh Michihiro Suzuki 《International journal of molecular sciences》2016,17(9)
The progression of chronic liver disease differs by etiology. The aim of this study was to elucidate the difference in disease progression between chronic hepatitis C (CHC) and nonalcoholic fatty liver disease (NAFLD) by means of fibrosis markers, liver function, and hepatic tissue blood flow (TBF). Xenon computed tomography (Xe-CT) was performed in 139 patients with NAFLD and 152 patients with CHC (including liver cirrhosis (LC)). The cutoff values for fibrosis markers were compared between NAFLD and CHC, and correlations between hepatic TBF and liver function tests were examined at each fibrosis stage. The cutoff values for detection of the advanced fibrosis stage were lower in NAFLD than in CHC. Although portal venous TBF (PVTBF) correlated with liver function tests, PVTBF in initial LC caused by nonalcoholic steatohepatitis (NASH-LC) was significantly lower than that in hepatitis C virus (C-LC) (p = 0.014). Conversely, the liver function tests in NASH-LC were higher than those in C-LC (p < 0.05). It is important to recognize the difference between NAFLD and CHC. We concluded that changes in hepatic blood flow occurred during the earliest stage of hepatic fibrosis in patients with NAFLD; therefore, patients with NAFLD need to be followed carefully. 相似文献