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61.
Objective To investgate the effects of TGF β 3 on rat hepatic fibrosis. Methods The TGF β 3 cDNA was cloned into rAAV2 vector. Rats were randomly divided into four groups: normal control group, model group, negative control group and TGF β 3 group. Hepatic fibrosis was induced by hypodermic injection of 40% CCI4. Recombinant AAV2-TGF β 3 viral particles were injected via the vena caudalis one week before CCh treatment. Rats were executed 8 weeks after CCI4 treatment, global histological change was observed after HE staining, the distribution of the collagen fibers was observed after masson staining, his-tochemistry was done to observe the expression of collagen Ⅰ; The positive area rate of the collagen fibers and the average optical rate of collagen Ⅰ were quantified. Results HE staining indicated that collagen fibers were reduced in the TGF β 3 group. Masson staining shown that the collagen fibers were distributed around the blood vessel, in the portal area and disse space. Compared to the model group (13.2%±2.2%) and negative control group (12.3%±1.5%), the collagen fibers in liver tissues of TGF β3 group (7.7% ± 1.5%) were significantly decreased (q = 9.456, P < 0.01; q = 8.217, P < 0.01). Histochemistry indicated that the collagen fibers of liver tissues of TGF 15 3 group (0.185±0.033) were significantly higher than those in the model group (0.252±0.042) and the negative control group (0.230±0.029), (q = 6.228, P < 0.01; q = 4.346, P < 0.01). Conclusion TGF β 3 alleviates the damage to hepatic cell and the level offibrosis in CCI4 treated rats and inhibits the expression of collagen Ⅰ. 相似文献
62.
本文采用1:3病例对照研究方法,对甾体避孕药的使用与血栓栓塞性疾病(急性心肌梗塞、脑栓塞、脑血栓形成和深静脉血栓形成)间的关联进行多因素分析。结果提示在我国广泛应用的甾体避孕药(主要为国产Ⅰ号避孕药)并不增加血栓栓塞性疾病的危险性。用药和停药时间的长短与血栓栓塞性疾病的发生无关,并与高血压病之间亦不存在协同作用。 相似文献
63.
目的探讨大学生的自我和谐与交往焦虑的特点和关系。方法采用自我和谐量表和交往焦虑量表对310名大学生进行调查。结果男生在自我灵活性和自我和谐上得分低于女生(P〈0.01),研究生在自我灵活性上得分低于本科生(P〈0.01),理科生在社交焦虑上得分低于文科生(P〈0.05);高自我和谐组在社交焦虑上得分低于低自我和谐组(P〈0.05);从总体上看,社交焦虑与自我与经验的不和谐、自我刻板性、总体的自我和谐均呈正相关(P〈0.01)。结论大学生的自我和谐和社交焦虑之间均存在相关,自我和谐对社交焦虑具有良好的预测作用。 相似文献
64.
<正> 患者男性,52岁,突发上腹痛6 h来诊。疼痛呈持续性,无放射痛,无呕吐、腹泻、黄疸。既往有胃溃疡病史。查体:神清,T37.8℃,痛苦面容,平卧位,巩膜皮肤无黄染,心肺(-),上腹部压痛,轻度肌卫,无反跳痛,肝浊音界存在,移动性浊音(-),肠鸣音减弱。化验:WBC12.0×10~9/L、中性0.87。腹 相似文献
65.
目的:探讨局部应用白细胞介素-12(IL-12)对于小鼠皮下肿瘤的治疗作用.方法:小鼠右侧腹部皮下注射2x105 个Panc-02细胞建立皮下肿瘤模型.皮下肿瘤被检测24d,通过测量的皮下肿瘤的两个直径以计算出肿瘤大小(mm2).分为IL-12治疗组和对照组,每组6只小鼠.从第3~7天,IL-2治疗组,每天在肿瘤周围注射0.1 μg IL-12,对照组同时同部注射同量平衡盐水.结果:与对照组相比,IL-12治疗组从第7天开始Panc-02肿瘤的生长出现受到抑制.第10天,IL-12治疗组[(13.8±8.7) mm2]与对照组[(36.4±8.5) mm2],(P<0.05)之间的差异有统计学意义(P<0.05).第24天,两组之间的差异更加明显[(66.5±50.4) mm2 VS (264.4±46.4 )mm2, P<0.01].结论:肿瘤周围注射IL-12明显抑制Panc-02皮下肿瘤的生长,为应用于临床肿瘤治疗提供可能性. 相似文献
66.
QIN Jian LIU Hong-jian DENG Wei WU Guo-zhen CHEN Shu-qing JING Ming-hua 《中国生物医学工程学报(英文版)》2005,14(3):114-119
Based on the fuzzy characteristic of the pulse state and syndromes differentiation thinking mode of TCM, an information fusing recognition method of pulse states based on SFNN (Stochastic Fuzzy Neural Network) is presented in this paper. With the learning ability in parameters and structure, SFNN fuses the measurement information of three pulse-state sensors distributed in Cun, Guan, and Chi location of body for the pulse state recognition. The experimental results show that the percentage of correct recognition with new method is higher than that by single-data recognition one, with fewer off-line train numbers. 相似文献
67.
The disaccharide trehalose is a key element involved in anhydrobiosis (the capability of surviving almost complete dehydration) in many organisms. Its presence also confers resistance to desiccation and high osmolarity in bacterial and human cells by protecting proteins and membranes from denaturation. The present study used a novel murine dry eye model induced by controlled low-humidity air velocity to determine whether topically applied trehalose could heal ocular surface epithelial disorders caused by ocular surface desiccation. In addition, the efficacy of 87.6 mM trehalose eyedrops was compared with that of 20% serum, the efficacy of which has been well documented. Mice ocular surface epithelial disorders were induced by exposure of murine eyes to continuous controlled low-humidity air velocity in an intelligently controlled environmental system (ICES) for 21 days, which accelerated the tear evaporation. The mice were then randomized into three groups: the control group received PBS (0.01M) treatment; a second group received 87.6 mM trehalose eyedrops treatment; and the third group received mice serum eyedrops treatment. Each treatment was administered as a 10 μl dose every 6 h for 14 days. The resultant changes in corneal barrier function and histopathologic examination of cornea and conjunctiva were analyzed and the level of apoptosis on the ocular surface was assessed using active caspase-3. After 14 days of treatment, the corneal fluorescein staining area, the ruffling and desquamating cells on the apical corneal epithelium, as well as the apoptotic cells on ocular surface epithelium had significantly reduced in eyes treated with trehalose compared with those treated with serum and PBS. In contrast, after 14 days of treatment, improvements in the thickness of the corneal epithelium, the squamous metaplasia in conjunctival epithelium and the number of goblet cells of the conjunctiva were less marked in eyes treated with trehalose compared with serum. These results demonstrated that trehalose could improve the appearance of ocular surface epithelial disorders due to desiccation through suppression of apoptosis. Trehalose produces some of the same responses as serum upon topical application and can maintain corneal health. 相似文献
68.
白藜芦醇抑制胶质瘤细胞生长与诱导细胞凋亡实验研究 总被引:6,自引:3,他引:3
目的探讨白藜芦醇(Res)对脑胶质瘤细胞(C6细胞株)和正常成纤维细胞(3T3细胞株)体外增殖的影响,进而观察Res诱导C6和3T3细胞系的凋亡作用.方法用不同浓度的Res处理C6和3T3细胞,以四甲基偶氮唑蓝(MTT)比色法检测Res对C6和3T3细胞的增殖作用,通过HE染色、扫描电子显微镜(SEM)、原位末端标记法(TUNEL)和流式细胞仪Annexin Ⅴ荧光染色,观察细胞的形态学结构改变,并定量检测细胞凋亡.结果 Res抑制了C6细胞的生长与增殖( P < 0.01 ),呈浓度依赖性反应;Res能明显诱导C6细胞凋亡,经210 μmol/L、120 μmol/L Res处理24 h后及对照组的C6细胞,其凋亡率分别为29.7%、14.6%及2.1%;相应的3T3细胞凋亡率分别为4.3%、3.5%、2.6%. 结论 Res能通过诱导C6细胞凋亡而抑制其生长与增殖,但对3T3细胞无此作用.本研究为临床应用Res治疗脑胶质细胞瘤提供了实验依据. 相似文献
69.
70.
本文将对呼吸机以下两种常见故障进行简要分析:①呼吸机在抢救病人过程中出现自动切断电源②呼吸机气道口湿度报警。 相似文献