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91.
目的 观察羟丁酸钠对缺血缺氧性脑损伤新生大鼠大脑皮层神经细胞凋亡的影响。方法 新生7dSD大鼠随机分为假手术组(S组)、生理盐水对照组(C组)和羟丁酸钠组(71、坦和档组)。每组按Ⅲ(缺血缺氧)后不同时间点进一步分为1h、3h、1d、3d、7d5个亚组(n=6)。按Rice法制作缺血缺氧性脑损伤模型。C、γ1、γ2和γ3组HI后即腹腔分别注射生理盐水0.2ml/10g、羟丁酸钠50、100、200mg/kg,3次/日;S组术后吸空气2h,腹腔注射生理盐水0.2ml/10g,3次/日。TUNEL染色法检测HI后各时间点大脑皮层凋亡神经细胞。结果 HI后1h~7d,C、γ1、γ2、γ3组凋亡神经细胞数高于S组(P〈0.05),且于HI后1d达高峰;HI后3h-3d,C、γ3组凋亡神经细胞数多于γ1、γ2组(P〈0.05),而C组与γ3组之间凋亡神经细胞数差异无统计学意义(P〉0.05);HI后7d,γ1组凋亡神经细胞数多于让组(P〈0.05)。结论 50、100mg/kg羟丁酸钠能抑制缺血缺氧性脑损伤新生大鼠大脑皮层神经细胞凋亡,且100mg/kg效果较好。  相似文献   
92.
目的研究先天性腹裂的肠管受损害情况,探讨该病术后并发症的原因。方法利用大鼠腹裂模型,运用组织学、生化学和免疫组织化学方法,分析腹裂胎鼠肠管的组织结构,DNA和蛋白质,细胞增生和凋亡等方面的改变。结果共获得腹裂胎鼠16只,对照胎鼠21只。与对照组相比,腹裂鼠肠管变短、充血水肿、粘连,肠壁表面纤维覆盖,壁内胶原沉积,DNA总量下降,蛋白质总量基本不变,细胞增生率下降,凋亡率上升。结论腹裂的肠管损伤是多方面的,是术后肠管运动和吸收功能异常的原因,大鼠的腹裂模型是对先天性腹裂的病因、病理等方面研究的合适工具。  相似文献   
93.
目的 :探讨恶性和非恶性肿瘤患者正常组织细胞生物学特性的区别。 方法 :用流式细胞术对 2 37例恶性肿瘤患者和 148例非恶性肿瘤患者正常组织细胞的DNA含量进行了检测 ,并对二者的DNA指数 (DI)、DNA倍体类型、细胞程序性死亡水平 (Apo)和增殖活性 (SPF)做了对比分析。 结果 :2 37例恶性肿瘤患者正常组织的DI值为1.0 8± 0 .2 3,DNA异倍体检出率为 18.99% ;148例非恶性肿瘤患者正常组织的DI值为 1.0 0± 0 ,DNA倍体类型均为二倍体。恶性肿瘤患者正常组织的Apo和SPF均显著高于非恶性肿瘤患者正常组织 (P <0 .0 5 )。即使剔除DNA异倍体病例 ,其Apo和SPF仍显著高于非恶性肿瘤患者的正常组织 (P <0 .0 5和P <0 .0 1)。 结论 :恶性肿瘤患者癌旁远处组织DNA二倍体细胞的Apo和SPF显著高于非恶性肿瘤正常组织 ,不能真正代表正常组织细胞的生物学特性  相似文献   
94.
目的探讨护理管理路径在应用佩尔地平治疗的重度子痫前期病人的效果,以期达到最佳的治疗效果,并减少并发症的发生。方法将用佩尔地平针治疗的重度子痫前期的病人486例随机分为两组,一组按常规护理,另一组按制定的护理管理路径护理。结果患者依从性对照组为168例,占70%;观察组为228例,占92.68%,P〈0.05,其差异有统计学意义。胎死宫内发生率对照组为9.16%,观察组为0.81%,P〈0.05,其差异有统计学意义。血压的稳定性对照组为36.3%,观察组为97.6%,P〈0.05,其差异有统计学意义。结论护理管理路径可以提高重度妊娠高血压疾病的治疗效果,减少并发症的发生。  相似文献   
95.
BACKGROUND: Change in apoptosis in gastric glands after eradication of Helicobacter pylori has never been reported. AIMS: The purpose of this paper is to investigate the change in apoptosis in gastric glands after eradication of Heliobacter pylori. PATIENTS AND METHODS: We studied 23 Heliobacter pylori-positive patients with duodenal and gastric ulcers, who were monitored for 6-12 months after eradication, and eight controls. Biopsies were taken from the antrum and body. Apoptosis was evaluated immunohistochemically using anti-single stranded DNA antibody. Apoptotic index was calculated by counting immunostained cells in surface epithelial and glandular cells. RESULTS: In the surface epithelium, Apoptotic indexes were significantly higher in patients than in controls. In the upper portion of fundic glands, apoptotic indexes were significantly higher in patients with gastric ulcers (14.2% (9.3, 17.8)) (median (1st quartile, 3rd quartile)) than in controls (8.0% (2.0, 9.0), p < 0.01) and decreased significantly after eradication (3.4% (2.0, 5.3)), p < 0.01). In pyloric glands, apoptotic indexes were no different between patients and controls. In the lower portion of fundic glands, apoptotic indexes were very low, both in patients and in controls. CONCLUSIONS: Our results showed that apoptosis, not only of surface epithelial cells but also of glandular cells in the upper portion of fundic glands, increased in Heliobacter pylori-positive patients with gastric ulcers and decreased to normal levels after eradication of Heliobacter pylori.  相似文献   
96.
电镜和荧光显微技术在细胞凋亡研究中的应用   总被引:8,自引:0,他引:8  
目的:探讨荧光显微技术在检测细胞凋亡中的作用。方法:应用拓扑异构酶Ⅱ抑制剂VP-16及化学毒物叠氮钠分别诱导HL-60细胞凋亡和死亡,用透射电镜和经Hoechst 33258染色的荧光显微镜对凋亡及死亡动态观察和定量分析。结果:HL-60细胞在VP16处理后,荧光显微镜下可见核浓缩、染色质凝集、核碎裂等凋亡特征;而叠氮钠诱导的细胞死亡则出现核溶解、核染色质弥散,但无上述改变;两者电镜的观察与荧光显微镜的改变一致;凋亡细胞及坏死细胞荧光显微镜下呈不同的形态特征。对处理的不同时间点细胞的荧光显微镜观察发现:处理后4h核形态开始变化,有核浓缩的细胞比例在处理8h达高峰,然后下降,核碎裂细胞的比例在24h达高峰,约占80%,表明核浓缩发生在核碎裂之前。结论:荧光显微镜技术可明确观察判断细胞凋亡及坏死,并可进行动态及定量分析,是良好的凋亡检测方法。  相似文献   
97.
Two different hepatoma cell lines were incubated for 48h with chemotherapeutic drugs cisplatin, paclitaxel and 5-FU to determine their ability to induce cytotoxicity and DNA fragmentation as well as to modify the expression of some cell death-related genes that could be involved in the resistance to therapy. We observed that cisplatin and paclitaxel induced cytotoxicity, but significant differences between both cell lines, were found only in the case of paclitaxel. At 48h, apoptosis was clearly present in Hep3B cells treated with cisplatin and HepG2 cells treated with paclitaxel. 5-FU induced cytotoxicity in both cell lines but only at higher concentrations than the other two drugs, triggering apoptosis and necrosis in HepG2 cells and only necrosis in Hep3B. When a time course was performed for the first 8h of treatment to elucidate the initial mechanism of cell death responsible for DNA fragmentation, we observed that 5-FU in Hep3B, and cisplatin in both cell lines, induces primary necrosis, whereas at the concentration tested here, paclitaxel clearly triggers apoptosis in both cell lines. HepG2 cells were weakly sensitive to 5-FU in the first 8h of treatment, so the primary mechanism of cell death was not clear, but results seem to indicate that it could be apoptosis. At 48h, Bax was not up-regulated with any of the treatments, whereas cisplatin was able to induce Bcl-xL down-regulation in both cell lines. Treatment with 5-FU also down-regulated Bcl-xL in HepG2 cells. We also measured variations in the expression of survivin, an inhibitor of apoptosis that has also been involved in mitototic catastrophe. Hep3B cells seem to show an increase in protein levels with all treatments. Exposure to paclitaxel resulted in the highest effect. In the case of HepG2 cells, there was a decrease in survivin expression when cells were treated with 5FU and paclitaxel, both treatments showing complete loss of the protein. Using an antibody that recognizes unprocessed caspase-3, we observed that the enzyme was assumingly activated in HepG2 cells treated with 5FU and paclitaxel, but only weakly after treatment with cisplatin. Hep3B cells did not show activation since the levels of the pro-enzyme remained the same as that in the control. In conclusion, the three drugs tested in this study could induce cell death, with paclitaxel being more effective inducing apoptosis. 5FU was only effective at high doses and its mechanism seems to be primarily related to necrosis in Hep3B and probably apoptosis in HepG2. Cisplatin mechanism of cell death is probably mediated by the decrease in anti-apoptotic protein Bcl-xL whereas paclitaxel and 5FU are decreasing the apoptosis inhibitor survivin. According to pro-enzyme levels, caspase-3 was only activated in HepG2 cells, whereas in the case of Hep3B cells the mechanisms of toxicity appear to be caspase-3-independent at the time and concentrations tested in this study. The resistance of Hep3B cells to death induced by chemotherapy could be related to an increase in the expression of IAP survivin, which can decrease cell response to the treatment or even switch the type of death from apoptosis to another kind, making therapy less efficient.  相似文献   
98.
Intra-uterine immunization of mice with paternal allogeneic or xenogeneic (rat) splenocytes was found to increase embryo tolerance to cyclophosphamide (CP)-induced teratogenesis. As the CP-induced teratogenic effect was shown to be associated with apoptosis, the present study was designed to investigate whether the protective effect of immunopotentiation may be realized via an alteration of CP-induced apoptosis. Various doses of CP were injected intraperitoneally into ICR mice on day 12 of pregnancy. Intra-uterine immunization with xenogeneic rat splenocytes was carried out 3 weeks before mating. Implantation sites, resorptions, live and dead fetuses, as well as soft tissue anomalies and external malformations, were recorded to evaluate the CP-induced embryotoxic effect. In parallel, flow cytometric analysis and DNA fragmentation assay were used for evaluation of CP-induced apoptosis in limbs, tail and whole embryos. The treatment of mothers with a high dose of CP induced the death of almost all embryos and striking fetal growth retardation in survivors. This strong embryotoxic effect was accompanied by very prominent DNA degradation in cells collected from whole embryos. Immunostimulation caused a dramatic decrease of embryonal loss (by ˜ 50%) and a significant (about 30%) increase in fetal weight. Such an increase in fetal survival and in fetal weight was found to be accompanied by a clear decrease in apoptosis level in embryo cell populations as judged by DNA gel electrophoresis with subsequent quantitation of DNA fragmentation in negatives by an image analysis technique. After treatment with a low dose of CP, a decrease in the proportion of fetuses with limb and tail anomalies in immunized females was accompanied by a decrease in the proportion of apoptotic nuclei in cells taken from limbs and tails. The results of this study suggest that the teratogen-induced apoptosis may, at least partly, be dependent on fetomaternal immune interactions.  相似文献   
99.
The binding of human complement components C3, C5 and C9 to the surface of the infective larvae of the nematode parasites Toxocara canis and Trichinella spiralis, by the alternative pathway, was examined by direct and indirect immunofluorescence on the intact parasites. This showed that although C3 bound to both nematodes, they differed markedly in the binding of C5 and C9; C5 bound only minimally to T. spiralis, and C9 binding to this parasite was barely detectable. In contrast, both early and late components bound to T. canis to a high density, comparable to, or in excess of, the binding of these components to the infective larvae of the trematode Schistosoma mansoni. The lack of binding of the post-C3 components to T. spiralis did not correlate with enhanced binding of the control protein, Factor H.  相似文献   
100.
瘢痕疙瘩成纤维细胞p53基因突变的研究   总被引:5,自引:0,他引:5  
目的 探讨瘢痕疙瘩成纤维细胞中 p5 3基因第 4~ 8外显子的突变规律及其意义。 方法 取瘢痕患者手术切除的瘢痕疙瘩和增生性瘢痕标本各 12例 ,并设患者自身正常皮肤标本及血标本为对照。体外分离、培养上述组织标本的成纤维细胞。采用聚合酶链式反应 单链构象多态性(PCR SSCP)分析方法和基因测序法 ,检测各种组织成纤维细胞中p5 3基因的突变情况。  结果  12例瘢痕疙瘩标本中有 9例p5 3基因外显子 4、5、6、7出现点突变和移码突变 ,增生性瘢痕标本、正常皮肤标本及血标本中均未检出突变。 结论 p5 3基因突变是瘢痕疙瘩形成和发展的重要因素之一。  相似文献   
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