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71.
72.
Saika T Tsushima T Nasu Y Arata R Kaku H Akebi N Kusaka N Kumon H 《Acta medica Okayama》2003,57(6):293-297
The aim of this study was to reveal the clinical features of anterior urethral recurrence in patients with superficial bladder cancer, and to determine the appropriate treatment. Three hundred and three patients with superficial bladder cancer, who were newly diagnosed and initially treated conservatively in our hospital between 1965 and 1990, were followed for at least 5 years and their clinical outcomes were analyzed. Clinical factors, including anterior urethral recurrence, were evaluated statistically regarding tumor progression. Eight patients (2.6%) had anterior urethral recurrence following superficial bladder cancer. Twenty-four patients (7.9%) had tumor progression and 149 (49.2%) had tumor recurrence. In a multivariate analysis using a logistic model, anterior urethral recurrence was the most important factor, followed by histological grade. Four of 5 patients who were treated for anterior urethral recurrent tumors by transurethral resection showed progression and died of the cancer within one year. Two of the remaining three patients who underwent radical cysto-urethrectomy at the time of anterior urethral recurrence survived. Anterior urethral recurrence following superficial bladder cancer is a predictor for rapid subsequent malignant progression. Once there is anterior urethral recurrence, radical intensive therapy, including radical cysto-urethrectomy, should be carried out immediately. 相似文献
73.
Naoki Yoshimi Chiken Shibuya Yukio Morishita Takuji Tanaka Hideki Mori 《Pathology international》1993,43(12):730-735
The relationship between the numerical aberrations of chromosome 7 in interphase cells and the clinicopathological behavior of breast tumors was investigated in 51 touch imprinted preparations of breast tumors. Using fluorescence in situ hybridization with a chromosome 7-specific DNA probe, the fluoresceinisothiocyanate (FITC) spots mean and the representative copy number of each breast tumor were examined. The FITC spots mean (2.34) of 40 breast cancers increased compared with that of 11 benign lesions (1.98) (P < 0.02). The FITC spots mean tended to increase with the advancing stage and tumor size of the breast cancer. The FITC spots mean in the case with metastasis was also of a higher value than that without metastasis (P < 0.01). Furthermore, the existence of trisomy or over-trisomy of the copy number was related to the advancing stage and tumor size (P < 0.05 and P < 0.01, respectively). These findings suggest that the FITC spots mean and polysomy of the number of chromosome 7 may be highly predictive for breast tumor aggressiveness. 相似文献
74.
The mechanism of the effect of intracellular ATP on the hyperpolarization-activated non-selective cation current (Ih) in rat dorsal root ganglion neurons was investigated using a whole cell voltage-clamp technique. Under voltage-clamp conditions, Ih was activated by hyperpolarizing pulses raised to a voltage of between -70 and -130 mV. The activation curve of Ih in rat dorsal root ganglion (DRG) neurons shifted by about 15 mV in the positive direction with an intracellular solution containing 1 mM cAMP. When ATP (2 mM) was applied intracellularly, the half-maximal activation voltage (Vhalf) of Ih shifted from -97.4 +/- 1.9 to -86.8 +/- 1.6 mV, resulting in an increase in the current amplitude of Ih by the pulse to between -80 and -90 mV. In the presence of an adenylate cyclase inhibitor, SQ-22536 (100 microM), the intracellular dialysis of ATP also produced a shift in the voltage-dependence of Ih in rat DRG neurons, indicating that the effect of ATP was not caused by cAMP converted by adenylate cyclase. Intracellular dialysis of a nonhydrolysable ATP analog, AMP-PNP or ATP-gamma-S, also produced a positive shift in the voltage-dependence of Ih activation, suggesting that the effect of ATP results from its direct action on the channel protein. These results indicate that cytosolic ATP directly regulates the voltage dependence of Ih activation as an intracellular modulating factor. 相似文献
75.
The human non-classical MHC class I molecule HLA-E is a ligand for both an inhibitory NK cell receptor (CD94/NKG2A) and an activating receptor (CD94/NKG2C). To identify HLA-E surface recognized by both receptors, especially to determine if both receptors recognize the same epitope, we made a series of individually Ala-substituted HLA-E proteins and analyzed their binding to CD94/NKG2A orCD94/NKG2C. Eight HLA-E mutations that significantly impaired HLA-E binding to CD94/NKG2A are all found in the top of alpha1/alpha2 domain of HLA-E. These results suggest that CD94/NKG2A binds a HLA-E surface equivalent to a NKG2D binding site on MICA. Of the eight mutations that impaired HLA-E binding to CD94/NKG2A, six significantly impaired HLA-E binding to CD94/NKG2C suggesting that CD94/NKG2C also binds a similar surface of HLA-E. Unexpectedly, the two HLA-E mutations (D69A and H155A) selectively abrogated HLA-E binding to CD94/NKG2A, not largely affected CD94/NKG2C. These results indicate that a mostly shared, but partly distinct set of HLA-E residues is discriminated by the two receptors. 相似文献
76.
Effects of succinylated concanavalin A on infectivity and syncytial formation of human immunodeficiency virus 总被引:3,自引:0,他引:3
Toshio Matsui Susumu Kobayashi Osamu Yoshida Shin-ichi Ishii Yukichi Abe Naoki Yamamoto 《Medical microbiology and immunology》1990,179(5):225-235
The effects of various lectins on the infectivity of human immunodeficiency virus (HIV) type 1 was investigated. Among the 25 lectins investigated, 2 types of concanavalin A (Con A) and 3 types of phytohemagglutinin were found to inhibit HIV infection. Succinylated Con A (S-Con A) efficiently blocked HIV-induced formation of syncytia in a coculture of MOLT-4 cells and blocked cell-free infection by HIV of MT-4 cells. The HIV-binding study revealed that S-Con A only partially inhibited viral binding to cells, although the control Leu-3a monoclonal antibody strongly inhibited it. When S-Con A was added to cultures after the initiation of viral adsorption, the number of HIV antigen-positive cells that developed depended on the time interval before addition of the compound. S-Con A inhibited HIV infection even after viral binding to cells at 0 °C and further incubation at 37 °C for 1 day. These data suggest that S-Con A inhibited mainly the fusion process rather than viral binding to cells in exerting its anti-HIV activity. 相似文献
77.
Kubo N Myojin Y Shimamoto F Kashimoto N Kyo E Kamiya K Watanabe H 《International journal of molecular medicine》2005,15(3):401-406
Radioprotective effects of a water-soluble extracts from cultured medium of Ganoderma lucidum (Rei-shi) mycelia (designed as MAK) and Agaricus blazei (Agaricus) against the shortening of survival time or the injury of crypt by X-irradiation were investigated in male B6C3F1 mice. MAK and Agaricus at three different doses were mixed into basal diet into biscuits at 5, 2.5 and 1.25% and administered from 1 week before irradiation. MAK (5% group) significantly prolonged animal survival as compared with basal diet group (control group) after 7 Gy of X-ray irradiation at a dose rate of 2 Gy min(-1). At doses of 8, 10 and 12 Gy X-irradiation at a dose rate of 4 Gy min(-1) MAK (5% group) significantly increased crypt survival as compared to other groups. These results suggest that MAK can act as a radioprotective agent. 相似文献
78.
79.
80.
Yasunori Higuchi Yoichi Tamura Tomohisa Uchida Keiko Matsuura Naoki Hijiya Shunsuke Yamamoto 《Pathobiology》2004,71(1):1-11
We generated transgenic mice expressing osteopontin (OPN) under the control of the alpha(1)-antitrypsin promoter. These mice (OPN-T mice) expressed OPN mRNA in liver and kidney, and released a large amount of plasma OPN, which increased after stimulation with turpentine oil. Before sensitization, the number of CD4+ T cells in lymph nodes was significantly higher in OPN-T than nontransgenic mice, and that in spleen was slightly higher, whereas that of CD8+ T cells was no different between OPN-T and nontransgenic mice. After sensitization, the CD4+ T cell numbers in spleen increased significantly, while there were almost no changes in the CD8+ T cells in lymph nodes and spleen. The intensity of contact hypersensitivity responses to 2,4-dinitrofluorobenzene (DNFB) was obviously enhanced in OPN-T mice. In the delayed-type hypersensitivity (DTH) model elicited by DNFB, the number of CD8+ T cells among DNFB-2,4,6-trinitrobenzenesulfonic acid (TNBS)-peritoneal exudate cells was significantly higher in OPN-T than nontransgenic mice, while there was almost no difference in that of CD4+ T cells. Adoptive transfer experiments revealed that the enhanced reactivity is carried by CD4+ and CD8+ T cells, respectively, although the ability of transferring DTH was significantly lower in CD8+ than in CD4+ T cells. The enhancement of CD8+ T cell migration was observed in OPN-T mice. These results suggest that OPN induces a proliferation of effector CD4+ and CD8+ cells in cell-mediated reactions and plays a role in the migration of CD8+ T cells. 相似文献