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91.
目的 探讨严重创伤后肝细胞凋亡及坏死在急性肝功能障碍发病机制中的作用。方法复制多发性骨折合并休克的大鼠创伤模型,采用 Annexin-V-Flous、碘化丙锭(propidium iodid,PI)双标法经流式细胞仪检测创伤后各时间点肝细胞凋亡与坏死的数量变化,结合光镜、电镜和电泳观察细胞凋亡与坏死,并与肝功能变化相比较。结果创伤后早期肝细胞即发生凋亡和坏死,坏死肝细胞的数量进行性升高,与肝功能变化显著呈正相关;凋亡肝细胞在创伤后3h达高峰,部分凋亡肝细胞发生继发性坏死,其数量与肝功能变化显著正相关。结论肝细胞坏死与凋亡是严重创伤后肝功能损害的重要原因,坏死肝细胞是肝功能损害的直接因素,凋亡肝细胞通过发生继发性坏死加重肝功能损害。 相似文献
92.
抑肽酶预处理防护大鼠肝脏缺血再灌注损伤的实验研究 总被引:5,自引:1,他引:4
目的 探讨抑肽酶预处理对肝脏缺血再灌注损伤的防护作用。方法 SD大鼠80只,随机分为抑肽酶预处理和生理盐水预处理两组,观察肝脏缺血再灌注损伤引起及抑肽酶预处理的影响。结果 拟肽酶预处理组大鼠缺血再灌注损伤引起的血清谷丙转氨酶(ALT),谷草转氨酶(AST)活性及肝组织丙二醛(MDA)含量变化均显著低于生理盐水预处理组(P<0.01);肝细胞形态学异常改变也明显较生理盐水预处理组轻。结论 抑肽酶预处理对大鼠肝脏缺血再灌注损伤有明显的防治作用。 相似文献
93.
目的建立裸鼠原位肝癌耐药模型。方法培养肝癌细胞系HepG2,建立裸鼠的皮下肿瘤,形成“供瘤鼠”。开腹直视下将瘤块种植于裸鼠的肝包膜下建立原位肝癌模型,通过表阿霉素间歇腹腔化疗,建立裸鼠原位肝癌耐药模型。用体检、B超、CT、剖腹探查监测肝内瘤块生长情况。用逆转录聚和酶链反应(RT-PCR)和免疫组织化学方法检测肿瘤耐药基因mdrl-mRNA和p-gp蛋白的表达。结果(1)模型建立无手术死亡(0/25),种植成瘤率为88%(22/25),补种3例全部成功,耐药诱导成功率为80%(16/20);(2)诱导组mdrl-mRNA和P-gp蛋白的表达均明显高于对照组,分别约是对照组的23倍和13倍。结论成功地建立了与临床肝癌相似的裸鼠原位肝癌耐药模型,为进一步研究肝癌多药耐药基因的诊断和逆转提供了良好的动物平台。 相似文献
94.
95.
目的 探讨腹腔化疗或联合其他方法综合治疗晚期原发性肝癌的治疗效果.方法 72例不能手术切除的、合并门静脉癌栓、腹腔内转移或淋巴结转移的晚期肝癌,采取腹腔化疗或者联合TACE等其他方法治疗.5-氟尿嘧啶(5-FU)0.5~0.75 g,腹腔内注入1/日,连用10~15天,总量5.0~12.5 g,最后一天腹腔内注入丝裂霉素(MMC)10 mg或卡铂100 mg.7例胆管细胞癌联合使用健择800~1000 mg.结果 全组平均生存时间13.97±6.27月.累积1年、2年生存率分别为59.7%和30.6%.肝功能Child A级平均生存时间15.91±5.49月,B级8.55±5.09月,有显著性差别.结论 腹腔化疗或联合其他综合治疗方法是肝癌并腹腔内转移的有效治疗方法,可延长部分晚期肝癌患者的生存时间,改善生活质量. 相似文献
96.
Objective To investigate the effects of tissue specific cytosine deaminase/5-fluorocytosine (CD/5-FC) thermotherapy on hepatic metastasis of colonic carcinoma in nude mice. Methods Forty-five nude mice were randomly divided into control group, 5-FC group and 5-FC thermotherapy group according to the random number table (15 mice in each group). Mice models of hepatic metastasis of colonic carcinoma were established by portal vein injection of LoVo/CEACD cells. The hepatic metastasis rate and number of metastatic nodules of the 3 groups were compared by ehi-square test and one-way ANOVA. The pathological changes in tumor tissues and apoptotic index of tumor cells were observed. The expression of the CD gene in tumor tissues was detected by fluorescent quantitative RT-PCR and Western blot. Results The number of metastatic nodules and liver metas-tasis rate were 4.6±1.3 and 100.0% in control group, 2.2±1.0 and 60.0% in 5-FC group, 0.5±0.8 and 13.3% in 5-FC thermotherapy group, with statistical difference among the 3 groups (F=25.898, χ2=5.208, 19.548, 5.168, P<0.05). The mean apoptotic indexes of tumor cells of the 3 groups were 4.6%, 9.9% and 17.4%, respectively. Vacuolar degeneration, cell necrosis, cytolysis and apoptotic bodies were mostly observed in the 5-FC thermotherapy group. The expression of CD gene in tumor tissue was detected in all the groups. Conclusion Tissue specific CD/5-FC thermotherapy has inhibitory effects on the hepatic metastasis of LoVo cells transfected with CD gene. 相似文献
97.
98.
Jing‐Ping Zhang Limin Zheng Jiang‐Hai Wang Karl‐Eric Magnusson Xin Liu 《Phytotherapy research : PTR》2009,23(6):844-850
Ganoderma sinensis has been used widely in Oriental countries for the prevention and treatment of various diseases including cancer. Previous studies have shown that the lipid extract from Ganoderma exhibits direct cytotoxicity against tumor cells. Here, it is reported that the lipid extract from germinating G. sinensis spores, at lower concentrations that have no direct tumoricidal activity, induce potent antitumor immune responses in human monocytes/macrophages. Upon stimulation with the lipid extract, monocytes/macrophages exhibited markedly increased production of proinflammatory cytokines and surface expression of costimulatory molecules. Conditioned medium from stimulated cells effectively suppressed the growth of tumor cells. Apparently, the lipid extract triggered macrophage activation via a mechanism different from that associated with LPS. Moreover, it was observed that the lipid extract could partially re‐establish the antitumor activity of the immunosuppressive tumor‐associated macrophages. These results indicated that in addition to its direct tumoricidal activity, the lipid extract from G. sinensis spores could exert antitumor activity by stimulating the activation of human monocytes/macrophages. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
99.
《中国肿瘤临床(英文版)》2005,2(5)
OBJECTIVE The present study was designed to develop the "ThreeGrade Criteria" for radical resection of primary liver cancer (PLC) and to evaluate its clinical significance.METHODS Criteria for radical resection of PLC were summed up to 3 grades based on criterion development. Grade I: complete removal of all gross tumors with no residual tumor at the excision margin. Grade Ⅱ: on or the primary branches of the portal vein, the common hepatic duct or its dition to the above criteria, negative postoperative follow-up result including AFP dropping to a normal level (with positive AFP before surgery)within 2 months after operation, and no residual tumor upon diagnostic imaging.The clinical data from 354 patients with PLC who underwent hepatectomy were reviewed retrospectively. Based on the "Three-Grade Criteria" these patients were divided into 6 groups: Grade Ⅰ radical group,Grade Ⅰ palliative group, Grade Ⅱ radical group, Grade Ⅱ palliative group,Grade Ⅲ radical group, Grade Ⅲ palliative group. The survival rate of each group was calculated by the life-table method and the rates compared among the groups.RESULTS The survival rate of patients receiving radical treatment was better than those receiving palliative treatment (P<0.01). Survival improved as more criteria were applied. The 5-year survival rate of the patients in Grade Ⅰ, Ⅱ and Ⅲ who underwent radical resection was 43.2%,51.2% and 64.4%, respectively (P<0.01).CONCLUSION The "Three-Grade Criteria" may be applied for judging the curability of resection therapy for PLC. The stricter the criterion used,the better the survival would be. Adopting high-grade criteria to select cases and guide operations and strengthening postoperative follow-up would improve the results of hepatectomy for PLC. 相似文献
100.
邹清如 《中华现代妇产科学杂志》2005,2(9):789-790
目的探讨第一产程胎心监护异常的相关因素,提示处理措施。方法2004年1月1日。12月31日对我院226例第一产程胎心监护异常的相关因素进行回顾性分析。结果第一产程胎心监护异常为综合因素所致,胎儿高危因素为91.59%,母体高危因素为65.49%,产程处理因素为42.92%。结论第一产程胎心监护异常主要与胎儿因素、母体因素有关,提高产前检查质量、加强产程监护、正确选择分娩方式极为重要。 相似文献