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71.
72.
To investigate the possible role of peripheral-type benzodiazepine receptors (PBR) in hepatic encephalopathy, we examined expression of PBR in mouse brain following thioacetamide (TAA)-induced acute liver failure. Treatment of mice with TAA resulted in an increase in the number of binding sites of the PBR ligand [3H] Ro5-4864 to brain homogenates, with no significant change in affinity of the ligand. The order of potency of different ligands to compete against [3H] Ro5-4864 binding in the brain of TAA-treated mice was Ro5-4864 > PK11195 > diazepam > protoporphyrin IX, findings similar to those in the control. Northern blot analysis revealed an increase in PBR/isoquinoline binding protein (PBR/IBP) mRNA in mouse brain following TAA treatment, in a time- and dose-dependent manner. These results indicate that the increased number of PBR in the brains of TAA-treated mice relates to the induction of PBR/IBP expression and suggest that the induction of PBR in brain may contribute to pathogenesis of hepatic encephalopathy. 相似文献
73.
T Tokunaga K Kamigiri M Orita T Nishikawa M Shimizu H Kaniwa 《Canadian Metallurgical Quarterly》1996,49(2):140-144
On the basis of a questionnaire in a population study in the county of Nordland, Norway, the prevalence of palpitations and its associations to some lifestyle factors, depression and self-rated health were analysed. All the 10,497 residents aged 40 to 42 years were invited to participate, 82% attended, 87% of the attenders returned a questionnaire by mail, and 6436 subjects were included in this report. The prevalence of palpitations was 15% in men and 25% in women. Palpitations were significantly associated with coffee consumption, smoking, alcohol intoxication, physical inactivity, depression and poor self-rated health in the univariate analyses. In a logistic regression analysis, the relations between palpitations and lifestyle were weakened. Significant predictors for palpitations were depression and poor self-rated health in both sexes, in addition to heavy coffee drinking and physical inactivity in men and alcohol intoxication in women. In conclusion, palpitations were more firmly linked to depression and self-evaluated health than to lifestyle. 相似文献
74.
75.
M Tokunaga S Kato A Kawamura-Watabe R Tanaka H Tokunaga 《Canadian Metallurgical Quarterly》1998,14(14):1285-1295
Hsp70 is structurally composed of three domains, an amino-terminal ATPase domain, a proximal 18 kDa peptide-binding domain and a distal 10 kDa carboxy-terminal (C-terminal) domain. To dissect the functional significance of the distal 10 kDa domain, and the boundary region between the proximal and distal C-terminal domains of Kar2p in vivo in Saccharomyces cerevisiae, we constructed a series of plasmids which were truncated or had internal deletion mutations in this region. We found that all these mutations are recessive, and that the distal 10 kDa C-terminal domain, including the HDEL ER-retention sequence, is not essential for cell growth, although the major role of this 10 kDa C-terminal domain is due to the function of the HDEL ER-retention signal. We also found that the Kar2p region (Thr492-Thr512), corresponding to the beta 8-sheet in the peptide-binding domain, which constitutes the bottom plate of the binding pocket in E. coli DnaK, is essential for cell viability, and that the following Kar2p region (Glu513-Lys542), corresponding to alpha-helices A and B of E. coli DnaK, which was proposed to compose the lid of the binding pocket, is critical but not essential for yeast cell growth. This was further supported by the fact that the latter deletion showed a fully reversible ts phenotype in its growth and only a slight inhibitory effect on the secretion of alpha-amylase at non-permissive temperature. 相似文献
76.
A polarisation switchable microstrip array antenna is presented. This array consists of square patch antennas coupled in close proximity to a microstrip line. The polarisation state can be switched electrically by short- or open-circuiting the end of the feedline using a PIN diode. Fundamental characteristics of the proposed array are investigated by measurements performed at S-band to demonstrate the proposal. 相似文献
77.
78.
Retinochrome is a photo-isomerase of all-trans-retinal to the 11-cis-isomer for rhodopsin synthesis. This protein is probably folded into seven α-helices spanning the membranes. Upon irradiation, it is converted to metaretinochrome, via pre-lumi- and lumiretinochrome, which are stable under 50 and 250 K, respectively. A series of analogue studies revealed that the cyclohexene ring and 6-s-cis-twisted conformation are important for binding. Modification of the 14-position suggests close location of the 14-H to the counterion. 相似文献
79.
Obesity is commonly associated with insulin resistance. The etiology of insulin resistance syndrome such as syndrome X or deadly quartet is not clear. We have proposed visceral fat syndrome, in which fat accumulation is predominant in the intra-abdominal cavity, frequently accompanied by disorders of glucose and lipid metabolism, and also hypertension. Excess free fatty acid of the portal circulation may cause the enhancement of lipid synthesis and gluconeogenesis as well as insulin resistance, resulting in hyperlipidemia, glucose intolerance and hypertension and finally atherosclerosis. Enhanced production of PAI-1 by increased visceral fat may be partly responsible for the development of cardiovascular disease in patient with visceral fat assmulation. 相似文献
80.
Yuzo Fujita Kazuhiko Ookubo Hiroshi Tokunaga 《Journal of Network and Systems Management》1995,3(2):195-216
A service operation architecture and operation system platform are proposed that separate commonly used information from operations functions, and that use access control functions. This enables new applications to be developed more easily and increases operating efficiency. The operation system platform is related to several surrounding platforms, and requires standardized reference points such as CMIS/P and managed objects. A managed object methodology is a suitable approach for accessing the operation system platform, and managed object classes and methods are proposed for intelligent network service operations. This architecture and platform will allow telecommunication to meet the demands created by intelligent networks for enhanced customer services, more reliable operation systems, and lower development costs. On the basis of proposed platform, service surveillance prototype systems for free-phone services have already been developed, and the next versions of the service operations systems for virtual private networks services are being developed. 相似文献