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101.
Kazushige Kiguchi Masao Iwamori Yukari Mochizuki Takeshi Kishikawa Katsumi Tsukazaki Masahiko Saga Akira Amemiya Shiro Nozawa 《Cancer science》1998,89(9):923-932
Cells of the human tumor cell line RMG-1, derived from a clear-cell adenocarcinoma of the ovary, were injected intraperitoneally into nude mice, and the cells obtained from the tumor nodules in the mesenterium were found to form a larger number of, and larger-sized, tumor nodules than the original RMG-1 cells. The RMG-1-h cells, transferred into culture from the tumor nodules after a 4th in vivo passage, showed a dissemination potential as high as that of cells disseminating directly from the tissues, and exceedingly higher than that of RMG-1 cells. To assess the molecular bases of the different biological properties of RMG-1 and RMG-1-h cells, we compared the content and expression of various carbohydrate antigens in both cells. The chromosomal profile of RMG-1-h cells revealed their human origin and was identical to that of the original RMG-1 cells. In contrast to the broad histogram for the Lex-bearing cells among RMG-1 cells in flow cytometry, the weakly and moderately positive cells toward anti-Lex antibody were found to be eliminated from the histogram for the RMG-1-h cells, resulting in the enrichment of cells strongly expressing Lex, which may account for the high dissemination potential. In addition, the adhesion of RMG-1 cells to mesothelial cells was found to be significantly inhibited by pretreatment of the cells with anti-Lex antibody, indicating Lex-mediated cell-to-cell interaction between ovarian cancer cells and mesothelial cells. By TLC-immunostaining, two Lex-glycolipids, III3Fucα-nLc4Cer and V3Fucα-nLc6Cer were detected in both RMG-1 and RMG-1-h cells, and their total concentrations were not significantly different from each other. However, the hydrophobic moieties of Lex-glycolipids in RMG-1-h cells were different from those in RMG-1 cells, suggesting that a difference in the structure of the hydrophobic moieties of Lex is partly involved in the enhanced reactivity of RMG-1-h cells toward anti-Lex antibody. Thus, the high dissemination potential of ovarian cancer cells was shown to be mediated by the Lex-determinant and the Lex-bearing cells are enriched by repeated in vivo passage of the cells into nude mice. 相似文献
102.
103.
Siro Simizu Keiko Tanabe Etsu Tashiro Minoru Takada Kazuo Umezawa Masaya Imoto 《Cancer science》1998,89(9):970-976
In the present study, we found that inostamycin increased the ability of paclitaxel to induce apoptosis in Ms-1 cells. A considerably higher concentration of paclitaxel was required for the induction of apoptosis in Ms-1 cells than in other cell lines tested. Treatment of Ms-1 cells with inostamycin, an inhibitor of phosphatidylinositol (PI) synthesis, reduced the dosage of paclitaxel required to induce cell death by apoptosis. This effect of inostamycin is specific to Ms-1 cells, and inostamycin did not increase the cytotoxicity of other antitumor drugs such as adriamycin, vinblastine, methotrexate, cisplatin, etoposide, or camptothecin in Ms-1 cells. Addition of inostamycin to paclitaxel-treated cells caused a significant increase in the sub G1 peak, representing apoptosis, which was accompanied by a decrease in the G2/M peak seen in paclitaxel-treated Ms-1 cells, without affecting paclitaxel-inhibited tubulin depolymerization. Moreover, paclitaxel did not enhance inostamycin-inhibited PI synthesis. The expression levels of Bcl-2, Bax, and Bcl-XL were not changed following the co-treatment with inostamycin plus paclitaxel, whereas the activated form of caspase-3 was markedly increased. Thus, inostamycin is a chemosensitizer of paclitaxel in small cell lung carcinoma Ms-1 cells. 相似文献
104.
We investigated the type of T cell response involved in Meth A tumor rejection in primary immune and hyperimmune syngeneic mice. It was found that a CD4+ T cell-mediated delayed-type hypersensitivity (DTH) response activating non-specific killer cells such as macrophages, NK and LAK cells, without a specific CD8+ cytotoxic T lymphocyte (CTL) response, was the major immune response leading to Meth A tumor rejection in primary immune mice. In contrast, the specific CD8+ CTL response was the major response leading to the tumor rejection, in addition to CD4+ T cell-mediated DTH response, in hyperimmune mice. Analysis of CD4+ T cell clones established from primary immune and hyperimmune spleen cells indicated that a CD4+ T cell clone (C9) of primary immune mice (although only one clone was established) was of Th1 type, and induced cytotoxicity in accessory cells by classic DTH in vitro. Eight CD4+ T cell clones were established from hyperimmune spleen cells. Six out of the eight clones were of the Th2 type and two were Th0-like. However, no Th1-type CD4+ T cell clone was established from hyperimmune spleen cells. All of these CD4+ T cell clones, even the Th2-type clones, were capable of inducing cytotoxicity in vitro in T cell-depleted accessory cells, as in an in vitro DTH response. We postulate on the basis of these results that the T cell response leading to Meth A tumor rejection in vivo sequentially changed from a CD4+ T cell-mediated classic DTH response to a CD8+ CTL response, in addition to a cellular response mediated probably by Th2-type cells, during the process of repeated immunization. 相似文献
105.
异丙酚复合瑞芬太尼应用于单肺通气麻醉的临床研究 总被引:1,自引:0,他引:1
目的:研究异丙酚复合瑞芬太尼联合应用单肺麻醉时对肺内分流、PaO2、清醒的影响.方法:选择胸外科行肺叶切除24例病人,随机分为两组,A组:异丙酚复合瑞芬太尼静脉全麻组12例;B组:异丙酚复合吸入异氟醚麻醉组12例。A组:静脉泵注异丙酚50μg/kg/min与瑞芬太尼0.05μg/kg/min混合液维持麻醉;B组:静脉泵注芬太尼0.05μg/kg/min与氟派利多2.5μg/kg/min混合液、复合吸人异氟醚1%~2%维持麻醉,分别在麻醉前、TLV 30min(TLV1),OLV 30min、OLV 60min.再次TLV 30min(TLV2)、手术结束等5个时点抽取动脉血和混合静脉血进行血气分析。结果:OLV开始后,Qs/Qt于TLV时高于麻醉前与TLV1时,OLV 30min、60min时Qs/Qt达最高,B组在OLV 30min、OLV 60min时,Qs/Qt高于A组(P〈0.01)。结论:异丙酚和瑞芬太尼联合麻醉能改善动脉血氧和减少肺内分流,且容易清醒。 相似文献
106.
本文重点阐述和分析了CT图像中的几种噪声产生的原因和对图像的影响,并结合笔者多年的维修经验,从理论和实际相结合,介绍了几种实用的维修方法,提出了减小噪声提高图像质量的有效措施。 相似文献
107.
目的对比观察丙泊酚(P)与氯胺酮(K)、芬太尼(F)不同配伍用于小儿静脉麻醉的效果及其对患儿呼吸、循环的影响。方法90例手术患儿随机分为三组(每组30例),Ⅰ组:P+K+F;Ⅱ组:P+K;Ⅲ组:P+F。均用微量泵持续静脉注入麻醉药,观察各组患儿麻醉药物用量、术毕苏醒时间、镇静和镇痛的效果及麻醉期间呼吸、血流动力学变化。结果Ⅰ组与Ⅱ、Ⅲ组相比用药量明显减少,镇静和镇痛完善,对呼吸、循环的变化小,术毕苏醒时间较短(P<0.05)。结论丙泊酚复合氯胺酮、芬太尼全凭静脉麻醉用药少,镇静和镇痛完善,对小儿呼吸循环影响轻微且术毕苏醒快,优于丙泊酚复合氯胺酮或芬太尼。 相似文献
108.
Haberham ZL van den Brom WE Venker-van Haagen AJ de Groot HN Baumans V Hellebrekers LJ 《Brain research》2000,873(2):287-290
We investigated whether components from the rat Vx-MLAEP could be used to assess depth of anaesthesia induced by propofol. Propofol decreased MLAEP amplitudes and increased latencies. We propose that the P(16)-N(22) wave in the rat MLAEP is similar to the human P1, and that recovery of this wave during propofol anaesthesia correlates with behavioural measures of the regaining of consciousness. 相似文献
109.
Treatment of refractory complex-partial status epilepticus with propofol: case report 总被引:3,自引:0,他引:3
PURPOSE: We report a case of a 65-year-old woman who had a subarachnoid and intraventricular hemorrhage secondary to rupture of an anterior communicating artery aneurysm and developed nonconvulsive status epilepticus of the complex-partial type, refractory to phenytoin (PHT), phenobarbital (PB), valproate (VPA), and lorazepam (LZP). METHODS: Three weeks after diagnosis of nonconvulsive status epilepticus, general anesthesia was induced with propofol and titrated to burst suppression on the electroencephalogram (EEG). RESULTS: During propofol infusion, the serum VPA level declined markedly, and despite >3 g daily doses, did not return to the therapeutic range, until several days after propofol was discontinued. Continuous propofol infusion was stopped after 7 days, and the patient recovered consciousness. Despite further complications, she gradually regained normal function and was discharged home 4 months after surgery. CONCLUSIONS: This is the first case of nonconvulsive status epilepticus successfully treated with propofol. 相似文献
110.
Kognitive Störungen in der frühen postoperativen Phase nach Remifentanil/Propofol- und Sevofluran/Fentanylanästhesie 总被引:3,自引:0,他引:3
OBJECTIVE: In ambulatory anaesthesia the time required to recover from cognitive impairment should be as short as possible. The aim of this study was to compare the early cognitive recovery after remifentanil/propofol (R/P) and sevoflurane/fentanyl (S/F) anaesthesia. METHODS: Sixty patients scheduled for elective gynaecological laparoscopy and 24 female volunteers tested for the assessment of learning effects were investigated. After praemedication with midazolam anaesthesia was induced with propofol, atracurium and either 1 microgram/kg fentanyl or 1 microgram/kg remifentanil. For maintenance 0.25 microgram/kg/min remifentanil and 0.6 mg/kg/min propofol (R/P) or 1.7 vol% sevoflurane (S/F) were given. Both groups were ventilated with 30% oxygen in air and received metamizol for postoperative analgesia. Verbal Learning Test, Stroop Colour and Word Interference Test, Digit Symbol Substitution Test and Four Boxes Test were performed the day before surgery and 30 min, 1 h, 2 h and 4 h after termination of anaesthesia. RESULTS: For remifentanil/propofol cognitive function was still impaired 2 h (Verbal Learning) and 4 h (Stroop, Digit Symbol Substitution and Four Boxes Test) after termination of anaesthesia. After sevoflurane/fentanyl anaesthesia cognitive impairment lasted the same duration in Four Boxes Test, but shorter in Stroop and Digit Symbol Substitution and could not be found in Verbal Learning Test. CONCLUSION: The duration of cognitive impairment in the early postoperative period differed by the test procedures and the anaesthetic procedures used in this investigation. Recovery appeared to be faster after sevoflurane/fentanyl than after remifentanil/propofol at least in aspects of cognitive function. 相似文献