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91.
Harada K Okano C Kadoguchi H Okubo Y Ando M Kitao S Tamura Y 《International journal of molecular medicine》2003,12(4):621-625
Oxygen-related free radicals have been suggested as a cause of aging and various diseases, for example, various cancers and rheumatoid arthritis. A radical scavenger as an antioxidant has been sought in foods. Fish sauces are traditional Asian fermented seasonings. Using the luminol chemiluminescence method, the peroxyl radical scavenging capability of fish sauces was examined. From the IC50 values, many fish sauces have been shown to have a strong scavenging capability as well as soy sauces. A scavenging mechanism is also proposed. 相似文献
92.
Tsukamoto K Suzuki H Harada D Namba A Abe S Usami S 《European journal of human genetics : EJHG》2003,11(12):916-922
Molecular diagnosis makes a substantial contribution to precise diagnosis, subclassification, prognosis, and selection of therapy. Mutations in the PDS (SLC26A4) gene are known to be responsible for both Pendred syndrome and nonsyndromic hearing loss associated with enlarged vestibular aqueduct, and the molecular confirmation of the PDS gene has become important in the diagnosis of these conditions. In the present study, PDS mutation analysis confirmed that PDS mutations were present and significantly responsible in 90% of Pendred families, and in 78.1% of families with nonsyndromic hearing loss associated with enlarged vestibular aqueduct. Furthermore, variable phenotypic expression by the same combination of mutations indicated that these two conditions are part of a continuous category of disease. Interestingly, the PDS mutation spectrum in Japanese, including the seven novel mutations revealed by this study, is very different from that found in Caucasians. Of the novel mutations detected, 53% were the H723R mutation, suggesting a possible founder effect. Ethnic background is therefore presumably important and should be noted when genetic testing is being performed. The PDS gene mutation spectrum in Japanese may be representative of those in Eastern Asian populations and its elucidation is expected to facilitate the molecular diagnosis of a variety of diseases. 相似文献
93.
Takahashi HK Xue D Iwagaki H Tamura R Katsuno G Yagi T Yoshino T Mori S Nishibori M Tanaka N 《Clinical immunology (Orlando, Fla.)》2005,115(1):85-92
Prostaglandin E1 (PGE1) has therapeutic value for transplantations due to its microvascular activity. Interleukin (IL)-18, which is elevated in plasma during the acute rejection after organ transplantation, elicits the expression of intercellular adhesion molecule (ICAM)-1, B7.1, B7.2, CD40, and CD40 ligand (CD40L) on monocytes as well as the production of interferon (IFN)-gamma and IL-12 and proliferation of T-cells during the human mixed lymphocyte reaction (MLR) in an in vitro model of acute rejection. In contrast, PGE1 inhibits all the adhesion molecule expression, cytokine production and T-cell proliferation in the presence of IL-18. The effects of PGE1 depend on stimulation of the IP/EP2/EP4-receptor, and thus, PGE1 might have therapeutic potential for treating acute rejection due to its immune regulatory effect. 相似文献
94.
Yoshizawa M Sato T Tanaka A Abe K Takeda H Yambe T Nitta S Nosé Y 《ASAIO journal (American Society for Artificial Internal Organs : 1992)》2002,48(4):443-448
The present study has proposed a new method for estimating the pressure head (P(t)[mm Hg]) and flow (Q(t)[L/min]) of a centrifugal pump on the basis of voltage (V(t)[V]), current (I(t)[A]), and rotational speed (N(t)[k(rpm)]) of the DC motor for a pump without any additional sensors. In the proposed estimation method, two auto-regressive exogenous (ARX) models are employed. One ARX model has an output, P(t) or Q(t), and three inputs, VI(t) = V(t)I(t) and N(t) and the steady state gain (K) of the system from VI(t) to N(t). It can be assumed that K may include the information on viscosity of blood. The coefficient parameters of this ARX model are identified in an off-line fashion before implantation of the pump. After implantation, P(t) or Q(t) is estimated by the same ARX model with the already identified parameters. The other ARX model is used to identify Kon the basis of VI(t) and N(t) in an on-line fashion every time the viscosity of blood may change. In the experiment, a mock circulatory system consisting of a centrifugal pump and a reservoir with 37% glycerin or water was employed. The root mean square error between measured Q(t) and its estimate obtained from the proposed method was 1.66L/min. On the other hand, a different method based on a single ARX model with inputs of VI(t) and N(t), but without the additional input of K, yielded the corresponding estimation error of 2.22L/min. This means that the proposed method can reduce its estimation error by about 25% in comparison with a method that cannot cope with the change in blood viscosity. 相似文献
95.
Takahashi HK Morichika T Iwagaki H Tamura R Kubo S Yoshino T Mori S Akagi T Tanaka N Nishibori M 《Clinical immunology (Orlando, Fla.)》2003,108(3):274-281
Lipopolysaccharide (LPS) binds to LPS-binding protein (LBP) in plasma and is delivered to the cell surface receptor CD14 on human monocyte. LPS is transferred to the transmembrane signaling receptor toll-like receptor (TLR) 4. In the present study, the effect of histamine on the expression of CD14 on human monocytes was investigated. Histamine concentration- and time-dependently decreased the expression of cell surface CD14, whereas histamine did not decrease mRNA for CD14 nor increase soluble CD14 (sCD14). The inhibitory effects of histamine on CD14 expression were antagonized by H2-receptor antagonist, but not by H1 and H3/H4 antagonist. The effects of selective H2-receptor agonists, 4-methylhistamine and dimaprit, on CD14 expression mimicked that of histamine indicating that histamine regulated CD14 expression through the stimulation of H2-receptors. The pretreatment with histamine partially inhibited the LPS-induced TNF-alpha production in human peripheral blood mononuclear cells (PBMC). Such inhibition might be due to the down-regulation of CD14 expression on monocytes by histamine. 相似文献
96.
Changes in activity of superoxide dismutase in the human endometrium throughout the menstrual cycle and in early pregnancy 总被引:6,自引:3,他引:6
Sugino N.; Shimamura K.; Takiguchi S.; Tamura H.; Ono M.; Nakata M.; Nakamura Y.; Ogino K.; Uda T.; Kato H. 《Human reproduction (Oxford, England)》1996,11(5):1073-1078
To investigate the possible role of the superoxide radical andits scavenging system in the human endometrium, the immunohistochemicaldistribution of superoxide dismutase (SOD), activities of SODand lipid peroxide concentrations were studied in the humanendometrium throughout the menstrual cycle and in early pregnancy.The endometrial epithelium showed a positive immunostainingfor Cu, Zn-SOD and Mn-SOD throughout the entire menstrual cycleand in early pregnancy. In the stroma, weak immunostaining forCu, Zn-SOD and moderate immunostaining for Mn-SOD were observedin the predecidual cells in the late secretory phase. Decidualcells in early pregnancy showed strong immunostaining for Cu,Zn-SOD and Mn-SOD. Total SOD activity in theendometrium increasedfrom early proliferative phase to mid-late proliferative phaseand further increased in the mid-secretory phase, and decreasedin the late secretory phase. The total SOD activity in the endometriumofearly pregnancy was the same level as that in the mid-secretoryphase. Cu, Zn-SOD and Mn-SOD activitieschanged in a similarmanner to total SOD activity throughout the menstrual cycleand in early pregnancy. Lipid peroxide concentration in theendometrium increased from early proliferative phase to mid-lateproliferativephase and further increased in the late secretoryphase. However, lipid peroxide concentration in theendometriumof early pregnancy was the same as that in the midsecretoryphase. These results suggested thatthe superoxide radical andits scavenging system may play an important role in the regulationof humanendometrial function. 相似文献
97.
Eiko Arai Shuichi Nishimura Kenichi Tamura Mitsushiro Kida Tatsuro Ikeuchi 《Journal of human genetics》1994,39(4):433-437
Summary Distal deletion of chromosome 1q has been reported in nearly 30 patients, all being associated with a deletion ranging from the 1q42 or q43 band to 1qter region. Here, we describe a girl with 1q terminal deletion resulting from an unbalancedde novo translocation t(1;D or G)(q44; p11), as revealed by the presence of a satellited feature and an NOR-stained region at the tip of 1q. We suggest that most of the phenotypic abnormalities seen in patients with 1q distal deletion are attributable to the monosomy for band 1q44. 相似文献
98.
Tanaka K Tamura J Kawanabe K Nawa M Uchida M Kokubo T Nakamura T 《Journal of biomedical materials research. Part A》2003,67(1):200-207
Recently zirconia/alumina composites have been examined by many researchers as the new generation of bearing materials in total joint replacements. In this study, the phase stability of a Ce-TZP/Al(2)O(3) nanocomposite and conventional Y-TZP after aging, and its influence on wear resistance, were investigated. Very slight phase transformation was observed in both types of ceramics 18 months after the implantation of Ce-TZP/Al(2)O(3) or Y-TZP samples into rabbit tibiae. However, Y-TZP showed marked phase transformation (approximately 80%) after aging in an autoclave (121 degrees C) for 190 h or in physiological saline at 62 degrees C for 18 months, whereas the new composite remained almost resistant to degradation. According to the results of self-pairing pin-on-disk wear tests using ceramic specimens with or without autoclave aging, the wear factor was almost the same between Ce-TZP/Al(2)O(3) samples with and without aging (6.74 +/- 0.36 x 10(-8) and 6.04 +/- 0.95 x 10(-8) mm(3)/Nm, respectively). In contrast, although non-aged Y-TZP had the lowest wear factor (4.88 +/- 0.51 x 10(-8) mm(3)/Nm) of all specimens tested, aged Y-TZP showed 10-fold greater wear than nonaged Y-TZP. The present study suggests that Ce-TZP/Al(2)O(3) nanocomposite has much greater phase stability than Y-TZP, and that its wear properties are not influenced by aging. 相似文献
99.
Generators of visual evoked potentials for faces and eyes in the human brain as determined by dipole localization 总被引:4,自引:0,他引:4
Human visual evoked potentials were recorded during presentation of photos of human and animal faces and various face features. Negative waves with approximate peak latencies of 165 msec (N170) were bilaterally recorded from the occipito-temporal regions. Mean peak latencies of the N170 were shorter for faces than eyes only. Analyses of amplitudes of evoked potentials indicated that the N170 elicited by faces reflected activity of a specific neural system which was insensitive to detailed differences among individual faces regardless of species, and consequently suggest that this system might function to detect existence of faces in general. On the other hand, the mean amplitude of the N170 elicited by human eyes was significantly larger than those by animal eyes. These differences in response latencies and amplitudes of the N170 suggest existence of at least 2 different visual evoked potentials with similar latencies (i.e., N170) which are sensitive to faces in general and human eyes, respectively. Dipole source localization analysis indicated that dipoles for the N170 elicited by eyes were located in the posterior inferior temporal gyrus, and those for faces, located initially in the same region, but moved toward the fusiform and lingual gyri at the late phase of the N170. The results indicated that information processing of faces and eyes separated at least as early as the latency of the N170 at the posterior inferior temporal gyrus as well as the fusiform and lingual gyri, and might provide neurophysiological and anatomical bases to an initial structural encoding stage of human faces. 相似文献
100.