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排序方式: 共有7034条查询结果,搜索用时 156 毫秒
61.
Immunohistochemical analysis of MCT1, MCT2 and MCT4 expression in rat plantaris muscle 总被引:3,自引:1,他引:3
Takeshi Hashimoto Shinya Masuda Sadayoshi Taguchi George A. Brooks 《The Journal of physiology》2005,567(1):121-129
All three forms of recombinant low voltage-activated T-type Ca2 + channels (Cav 3.1, Cav 3.2 and Cav 3.3) exhibit a small, though clearly evident, window T-type Ca2 + current ( I Twindow ) which is also present in native channels from different neuronal types. In thalamocortical (TC) and nucleus reticularis thalami (NRT) neurones, and possibly in neocortical cells, an I Twindow -mediated bistability is the key cellular mechanism underlying the expression of the slow (< 1 Hz) sleep oscillation, one of the fundamental EEG rhythms of non-REM sleep. As the I Twindow -mediated bistability may also represent one of the cellular mechanisms underlying the expression of high frequency burst firing in awake conditions, I Twindow is of critical importance in neuronal population dynamics associated with different behavioural states. 相似文献
62.
Akagi T Higashi A Tsugami H Sakamoto H Masuda Y Hishikawa Y 《Physics in medicine and biology》2003,48(22):N301-N312
At the Hyogo Ion Beam Medical Center (HIBMC) we have developed a new design method for the bar ridge filter used in proton therapy, taking into consideration the scattering and nuclear interaction effects within the filter itself, which are introduced in the design. In our beam delivery system, the bar ridge filter is employed as the range modulator. It is combined with the wobbler system, and produces a three-dimensionally uniform spread-out Bragg peak (SOBP). The design program predicts the three-dimensional dose distribution. Ridge filters of 3-12 cm SOBP in 1 cm increments were designed in the maximum radiation field for 150 MeV and 190 MeV proton beams so that a uniform physical dose area is obtained in the SOBP region three-dimensionally. Measurements were performed with the constructed ridge filters to verify the uniformity and these were compared with the predictions of the design program. The predictions and measurements were found to be in agreement except for the 12 cm SOBP. The uniformities were better than +/- 3.0% for all SOBPs produced. The ridge filters are now clinically in use. 相似文献
63.
Synthetic peptides as antigens for the detection of humoral immunity to Plasmodium falciparum sporozoites 总被引:2,自引:0,他引:2
The presence of antibodies against P. falciparum sporozoites in humans living in malaria-endemic areas was measured using as antigen the synthetic peptide (NANP)3, which represents the immunodominant region of the circumsporozoite (CS) protein. By using a competitive binding assay it was determined that antibodies which recognize (NANP)3 do not react with a 22-Mer synthetic peptide representing a cross-reacting epitope present in an antigen (5.1) from the blood stages of the parasite. Antibodies present in human sera which react with the 5.1 peptide did not react with (NANP)3. This strongly suggests that antibodies to (NANP)3 found in sera of individuals living in endemic areas are a reflection of exposure to P. falciparum sporozoites. These results validate the use of (NANP)3 for epidemiological studies to detect and measure humoral immunity to P. falciparum sporozoites. 相似文献
64.
65.
Kupffer cell-mediated cytotoxicity against hepatoma cells occurs through production of nitric oxide and adhesion via ICAM-1/CD18 总被引:1,自引:0,他引:1
Saito Hidetsugu; Kurose Iwao; Ebinuma Hirotoshi; Fukumura Dai; Higuchi Hajime; Atsukawa Kazuhiro; Tada Shinichiro; Kimura Hiroyuki; Yonei Yoshikazu; Masuda Tetsuya; Miura Soichiro; Ishii Hiromasa 《International immunology》1996,8(7):1165-1172
Rat Kupffer cell (KC)-mediated cytotoxicity against both thesyngeneic hepatoma cell line AH70 and hepatocytes was evaluatedby changes in mitochondrial function, and the possible roleof ICAM-1/CD18 in the interaction between the cells was studied.Rhodamine 123 fluorescence, a marker of the mitochondrial membranepotential, decreased in AH70 cells after co-culture with KC,while that in hepatocytes was unchanged by co-culture. Thisdecrease was blocked by anti-ICAM-1, anti-CD18 and the Inhibitionof nitric oxide synthesis. Cytometric studies demonstrated thatICAM-1 expression on AH70 cells increased after addition ofIFN-, IL-1ß, tumor necrosis factor (TNF)- or KC, whilein hepatocytes ICAM-1 was not increased. Anti-ICAM-1 pretreatmentinhibited the increase in ICAM-1 expression and the decreasein rhodamine 123 fluorescence on AH70 cells after co-culturewith KC. CD18 on KC was increased only after co-culture withAH70. TNF- but not IFN- was detected in the supernatant of co-culturebetween KC and AH70 cells, and this production was partiallyinhibited by anti-ICAM-1 and anti-CD18. The activity of Induciblenitric oxide synthase in Kupffer cells and the levels of nitritesand nitrates in the co-culture supernatant increased over time,and this increase was attenuated either by addition of NO synthesisinhibitors, anti-ICAM-1 or anti-CD18. These results indicatethat the rat KC causes mitochondrial dysfunction in cancer cellsvia the production of NO and cell-to-cell adhesion via ICAM-1/CD18has an Important role in this cytotoxic process. 相似文献
66.
Keiko Wakui Toshiro Nishida Jun-ichiro Masuda Takeshi Itoh Daisuke Katsumata Tsutomu Ohno Yoshimitsu Fukushima 《Journal of human genetics》1991,36(2):149-153
We report a malformed female infant withde novo interstitial deletion of 4q[46,XX,del(4)(q27q28.2)]. The MN blood type analysis of the family members showed that the patient had an intact blood group-MN locus. The locus of the gene responsible for the MN antigen activity is confined to a 4q28.2–4q31.1 segment on the basis of the result of this patient and the previous mapping data. 相似文献
67.
Hozumi Katsuto; Kondo Motonari; Nozaki Hideki; Kobori Akiko; Nishimura Takashi; Nishikawa Shin-Ichi; Sugamura Kazuo; Habu Sonoko 《International immunology》1994,6(9):1451-1454
The effects of IL-7 on the growth and differentiation of thymocyteswere analyzed using murine fetal thymua organ cultures (FTOC)in the presence of mAbs specific for the conventional IL-7 receptor(1L-7R) and for the common (c) chain. In FTOC, the developmentof CD4–CD8– double-negative thymocytes to CD4+CD8+double-positive (DP) and CD4+ or CD8+ single-positive (SP) cellswas not completely blocked by adding these mAbs, although cellgrowth was reduced by the treatment. To define a developingstage sensitive to the mAbs, most immature thymocytes, Pgp-1+c-kit cells, were cultured in the 2-deoxyguartosine treatedfetal thymus. In the presence of both mAbs in the culture, neitherDP nor SP thymocytes developed whereas either of the mAbs partiallyblocked their development. These results indicate that the Cchain is involved in early T cell development as an indispensablesubunlt of the functional IL-7 receptor complex. 相似文献
68.
N Koga J Kuroki H Nakashima Y Hokama-Kuroki H Yoshimura H Kuroki Y Masuda 《Fukuoka igaku zasshi》1991,82(5):197-206
Acute toxicity, inductive effects of liver enzymes and liver persistency of 1,2,3,7,8-pentachlorodibenzo-p-dioxin (PenCDD) were compared with those of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) using male Wistar rats. 1,2,3,7,8-PenCDD treatment at a dose of 0.1 mumol/kg resulted in significant depression of growth of rats from a day to 28 days after treatment. However, the effect was relatively less than that of 2,3,7,8-TCDD. On 5 days, similarly to 2,3,7,8-TCDD-treated group, liver hypertrophy and thymic atrophy were observed in 1,2,3,7,8-PenCDD-treated groups. In addition, 1,2,3,7,8-PenCDD showed potent 3-methylcholanthrene-type inducing ability. For example, the activities of benzo(a)pyrene 3-hydroxylase and DT-diaphorase were 25-fold and 10-fold of control, respectively. On 30 days, about 50% of the inductive effects on 5 days were maintained in both 1,2,3,7,8-PenCDD- and 2,3,7,8-TCDD-treated groups. Amount of 1,2,3,7,8-PenCDD distributed to the liver on 5 days was about 80-90% of dose and was about 1.5 times greater than that of 2,3,7,8-TCDD. About 50% of dose of 1,2,3,7,8-PenCDD remained even on 30 days after treatment. From these results, it is suggested that 1,2,3,7,8-PenCDD possessing the potent acute toxicity comparable to 2,3,7,8-TCDD and higher persistency in the liver might be more important than 2,3,7,8-TCDD in terms of the chronic toxicity. 相似文献
69.
Yukinari Masuda Masamichi Ishizaki Nobuaki Yamanaka Yuichi Sugisaki Yozo Masugi 《Pathology international》1989,39(5):289-295
In order to investigate whether mesangial transport by glomeruli is delayed in ddY mice pretreated with sheep anti type IV collagen serum, the mice were administered an overload of human IgA myeloma serum. Non pretreated ddY mice used as controls and both experimental and control BALB/c mice were also processed in a similar manner. The intensities of mesangial deposition of human IgA were examined periodically and were found to correlate well with deposition of mouse IgA. Both mouse and human IgAs showed a gradual increase for up to 8 experimental weeks. In the control young ddY mice, however, the overloaded mesangial human IgA quickly disappeared, presenting no appreciable mesangial deposition of autologous IgA. In sharp contrast, both the experimental and control BALB/c mice showed an initially prolonged and rather heavy mesangial deposition of human IgA, followed by a gradual decrease and somewhat light mesangial deposition of autologous mouse IgA. These results obtained using experimental ddY mice appear to confirm the possibility that non immunological local trapping, due to retardation of mesangial transport function, causes mesangial deposition of autologous mouse IgA in this particular strain. Acta Pathol Jpn 39: 289 295, 1989. 相似文献
70.
Administration of excess vitamin A to rats causes gastric ulceration. In this study the effects on the gastric mucosa of excess vitamin A and excess prostaglandin E1, alone and in combination, were studied. Prostaglandin E1 protected against ulceration by vitamin A. Vitamin A labilized marker enzymes from four different membrane systems, namely those of the lysosomes, mitochondria, endoplasmic reticulum and plasma membrane, whereas only the effect on lysosomes was prevented by prostaglandin E1. Indeed, the prostaglandin alone labilized the enzymes from plasma membrane and endoplasmic reticulum and also damaged mitochondrial membranes. Both vitamin A and prostaglandin E1 caused a reduction in the total number and an increase in irregularly-shaped mitochondria in the parietal cells and produced dilation of the endoplasmic reticulum in both parietal and chief cells. It is noteworthy that prostaglandin E1 effectively prevents ulceration by vitamin A despite the extent to which it damages these membrane systems. These findings lend support to the hypothesis that vitamin A ulceration of the gastric mucosa is mediated via release of lysosomal enzymes, following damage to the lysosomal membranes. 相似文献